[Objective] This study aimed to assess the effects of adding different proportions of cassava alcohol residue on fermentation quality of micro-silage of Pennisetum purpureum Schum. cv. Gui Min Yin. [Method] Four treatment groups with different addition levels of cassava alcohol residue were set up using Pennisetum purpureum Schum. cv. Gui Min Yin as raw material. The proportions of Pennisetum purpureum Schum. cv. Gui Min Yin to cassava alcohol residue included in this study were 1∶1.38 （group Ⅰ）, 1∶1 （groupⅡ）, 1∶0.35 （group Ⅲ） and 1∶0.11 （group Ⅳ）. The initiative water content of the micro-silage was set to 40% （group Ⅰ）, 50% （group Ⅱ）, 60% （group Ⅲ) and 70% （group Ⅳ）. Commercial microbial additives were used to prepare mixed micro-silage. Single microbial fermentation of Pennisetum purpureum Schum. cv. Gui Min Yin without addition of cassava alcohol residue was set as the control group （CK group）. There were three replicates for each group. After 30 d fermentation, samples of the fermented micro-silage were taken to assess the sensory indicators, fermentation quality, nutritional components and digestibility. [Result] The sensory indicators of the prepared micro-silage with addition of different proportions of cassava alcohol residue were all better than those of CK group, with group Ⅱ being the best. The dry matter content among the varied groups were significant （P<0.05） different. In comparison to the other groups, the crude protein content in groups Ⅰ and Ⅱ was significantly （P<0.05） higher, and the crude ash content in groups Ⅰ and Ⅱ was significantly （P<0.05） lower. The content of neutral detergent fiber in group Ⅱ was significantly （P<0.05） lower than that in the other groups, and the content of acidic detergent fiber in group Ⅱ was significantly （P<0.05） lower than that in groups Ⅰ, Ⅳ and CK. The soluble carbohydrate content in groups Ⅰ, Ⅱ and Ⅲ was significantly （P<0.05) higher than that in groups Ⅳ and CK. The starch content in group Ⅱ was significantly （P<0.05） higher than that in the other groups. The calcium content in groups Ⅰ, Ⅱ and Ⅲ was significantly （P<0.05） higher than that in CK group, with group Ⅱ being the highest. In comparison to CK group, groups Ⅰ, Ⅱ and Ⅲ had significantly （P<0.05） lower levels of phosphorus. The contents of magnesium, potassium and chloride ions in groups Ⅰ, Ⅱ, Ⅲ and Ⅳ were significantly （P<0.05） lower than those in CK group. The 30 h in vitro dry matter digestibility of groups Ⅰ, Ⅱ and Ⅲ was significantly （P<0.05） higher than that of groups Ⅳ and CK, with group Ⅱ being the highest. Compared with CK group, the lactic acid content of the micro-silage of the cassava alcohol residue addition treatment groups was significantly （P<0.05） increased, while the acetic acid content was significantly （P<0.05） decreased. The ammonia content in groups Ⅰ and Ⅱ was significantly （P<0.05） lower than that in the other groups. [Conclusion] The addition of cassava alcohol residue improves the fermentation quality of the micro-silage of Pennisetum purpureum Schum. cv. Gui Min Yin. When the proportion of Pennisetum purpureum Schum. cv. Gui Min Yin to cassava alcohol residue is 1∶1 and the initiative water content is 50%, the fermentation quality of the micro-silage is the best.

[Objective] The aim of this study was to explore the effects of different microbial agents addition and different compaction densities on nutritional components and fermentation quality of corn silage. [Method] Four commercial microbial agents with two compaction densities （750 kg/m³ and 850 kg/m³）, and two microbial agent addition methods （adding the recommended level or the same level） were set up using whole plant silage corn as raw material. The recommended addition levels of the microbial agents A （group A, consisting of 7 bacteria such as Enterococcus faecalis and Lactobacillus paracasei）, B （group B, consisting of Lactobacillus buchneri and Lactobacillus plantarum）, C （group C, consisting of Lactobacillus buchneri, Lactobacillus plantarum and Pediococcus acidilactici） and D （group D, consisting of Lactobacillus plantarum and Lactobacillus buchneri） were 2.5×10¹¹, 1.1×10¹¹, 2.9×10¹¹ and 1.0×10¹² CFU/t, respectively. The same addition level of the four microbial agents was 5.0×10¹¹ CFU/t. Control groups without addition of microbial agents were set at the both compaction densities. After 120 d fermentation, samples of the corn silage were taken to measure and compare the nutritional components and fermentation indicators under different levels of microbial agents addition and at different compaction densities. [Result] At the compaction density of 750 kg/m³, when adding the recommended levels of the four microbial agents, the dry matter content in group D was higher than that in control group, and was significantly （P<0.05） higher than that in groups A and B. When the addition level of the four microbial agents was all 5.0×10¹¹ CFU/t, the dry matter content in group D was significantly （P<0.05） higher than that in control group. Compared with control group, adding the recommended levels and the same level of the four microbial agents all had trend of increase in the contents of crude protein, starch and lactic acid. Adding the recommended levels of the four microbial agents at the both compaction densities, the starch content increased by 5.61% to 9.23% and 2.49% to 6.71%, respectively, and the lactic acid content increased by 11.09% to 25.94% and 15.56% to 38.97%, respectively. At the compaction density of 850 kg/m³, when the addition level of the four microbial agents was 5.0×10¹¹ CFU/t, the dry matter content in groups C and D increased by 2.94% and 2.60% compared to control group, respectively. In comparison with control group, the addition of the recommended levels and the same level of the four microbial agents showed trend of decrease in the content of butyric acid. Overall, different compaction densities had limited effects on the nutritional components and fermentation quality of the corn silage. [Conclusion] Microbial agents addition improves the nutritional components and fermentation quality of corn silage. Higher level addition of the microbial agent consisting of Lactobacillus plantarum and Lactobacillus buchneri has better performance than lower level addition of the microbial agent with the same composition or combinative addition of multiple microorganisms.

A significant portion of agricultural carbon emissions are caused by animal husbandry. In this study, the application of current market-oriented tools for reducing carbon emissions in animal husbandry is reviewed together with the research progress made in this area. In order to serve as a guide for animal husbandry carbon emission reduction to participate in carbon market trading, this paper presents the research status as well as the feasibility and existing difficulties of market-oriented tools for carbon emission reduction in animal husbandry such as carbon tax and carbon market trading, and summarizes the application practice and experience of those tools.

[Objective] According to the characteristics of vast activity area, insensitivity to the environment and delayed movement of free range cattle population, by referring the existing animal body size measurement technology, a non-contact body size measuring system on the basis of unmanned air vehicle （UAV） off-line 3D reconstruction method capable of collecting cattle point cloud data was develped to establish a wide coverage, precise, and high-efficient cattle body size measurement solution. [Method] Firstly, a quad-axis UAV was used to capture images, and some image processing techniques such as noise reduction with median filter and image three-channel histogram equalization were utilized to preprocess the image and to improve the reconstructed point cloud density and measurement accuracy. Secondly, the aerial triangulation measurement was conducted using the position and orientation system （POS） information from the image, and the 3D model was reconstructed after the initial coordinate data of point cloud was confirmed by adjustment computation. Finally, the point cloud of individual cattle was extracted by using random sample consensus （RANSAC） algorithm in point cloud library （PCL） and then interactive measurement was made. [Result] Images from 4 cattle herds and 1 individual cattle were collected, and available point cloud of body size data from a total of 21 cattle were reconstructed. In comparision to the convetional manual measurement method, the average relative errors in body height, body length and chest circumference measured by the developed UAV based system were 3.87%, 4.16% and 5.06%, respectively. [Conclusion] The UAV based system developed in this study can be used to measure body size of medium- and low-density free range cattle herds in Inner Mongolia, and the error is within the acceptable range.

[Objective] The aim of the present study was to screen the soybean varieties suitable for silage maize-forage soybean intercropping model in the low plain areas of eastern Hebei Province. [Method] A total of 35 soybean varieties were selected as experimental materials. Each variety was planted in a 35 m²（5 m×7 m）plot, with 10 cm plant spacing and 40 cm row spacing, and planting density of 170 000 plants/hm². The plots were randomly distributed and repeated three times. The time for flowering, pod setting and grain filling stages of all the soybean varieties was recorded and their growth periods （the number of days from sowing to grain filling stage） were calculated. The soybean were harvested at grain filling stage with fresh weight yield measured. Five soybean plants were randomly selected from each plot and variety, with contents of crude protein （CP）, acidic detergent fiber （ADF）, neutral detergent fiber （NDF）, crude ash （Ash） and crude fat （CF） measured after deactivation, drying and crushing. The entropy weight TOPSIS comprehensive evaluation function in SPSSAU software was used to comprehensively evaluate and rank the feeding quality of all the soybean varieties, and a comprehensive analysis chart for the comprehensive evaluation and ranking of the growth period, fresh weight yield and feeding quality of various soybean varieties was created. [Result] Ruidou No.1 had the longest growth period of 100 days. The growth periods of You 6019, Jindou 99 and Andou 109 reached 97 days, and that of Pudou 5110 was 95 days. The growth periods of Zhonghuang 78, Beidou 17, Beidou 30, Fengdou No.3 and Lindou No.10 were the shortest, only 85 days. Suike 23 （40.48 t/hm²）, Suike 9 （38.34 t/hm²） and Hedou 12 （38.06 t/hm²） were the three varieties with the highest fresh weight yield. Sudou 16 （10.29%） had the highest crude ash content, followed by Jindou 99 （9.80%）, Suike 9 （9.76%） and Shengdi No. 1 (9.57%). The crude protein contents of Wandou 37 （29.17%） and Jiakedou No.1 （25.38%） were significantly （P<0.05） higher than the other varieties. The crude fat contents of Andou 109 （6.33%）, Fengdou No.3 （5.93%） and Wandou 15 （4.97%） were significantly （P<0.05） higher than the other varieties. The ADF contents of Fengdou No.3 （24.05%）, Lindou 10 （24.38%） and Wandou 37 （24.46%） were significantly （P<0.05） lower than the other varieties. The NDF contents of Suike 12 （31.52%）, Jindou 99 （32.82%） and Pudou 5110 （33.39%） were significantly （P<0.05） lower than the other varieties. The top five soybean varieties in the comprehensive evaluation of feeding quality were Jindou 99, Pudou 5110, Andou 109, Suike 12 and Wandou 37. The comprehensive analysis chart based on the overall evaluation and ranking of the growth period, fresh weight yield and feeding quality of different soybean varieties showed that four soybean varieties, Ruidou No.1, Andou 109, Pudou 5110 and Jindou 99, performed well in all the three aspects. [Conclusion] Ruidou No.1, Andou 109, Jindou 99 and Pudou 5110 could be used as candidate varieties for silage maize-forage soybean intercropping model in the low plain areas of eastern Hebei Province.

[Objective] This study was conducted to preliminarily explore the possible regulative mechanisms underlying yellow beef fat of local cattle in Hulun Buir City of Inner Mongolia. [Method] A total of 72 local cattle were selected from Hulun Buir City, and their subcutaneous fat and liver tissues were sampled. The subcutaneous fat samples were subjected to color scoring with a 5-point subjective scoring scheme. Using liver tissues as experimental materials, the penta-primer amplification refractory mutation system （PARMS） was employed to assess the genotype and gene frequency distribution of BCO2 SNPW80X, BCMO1 SNP4, RDHE2 SNP2, ALDH8A1 SNP16 and PPARCG1A SNP12, which were considered as the crucial genes in the signaling pathways involved in the metabolic process of β-carotene. The non-targeted metabolomics analysis of the fat samples were performed by liquid chromatography-mass spectrometry （LC-MS） technology to identify the differential metabolites in different colored fat samples, and the differential metabolites were subsequently subjected to metabolic pathway enrichment analysis. [Result] The 72 subcutaneous fat tissue samples were predominantly white colored, with yellow colored ones （scoring 3 or above） accounting for 30.55%. The SNPs in BCO2, BCMO1, RDHE2 and PPARCG1A genes were observed in different samples, while these SNPs had no significant （P>0.05） correlation with fat color. Compared with the white colored fat samples, a total of 235 differential metabolites were identified in the yellow colored fat samples, which were enriched in the signaling pathways such as unsaturated fatty acid biosynthesis, primary bile acid biosynthesis, and bile secretion. [Conclusion] Comparing the yellow and white colored fat samples collected from the local cattle in Hulun Buir City, there were multiple differential metabolites involving in the signaling pathways closely related to fat formation, in vivo β-carotene transport and trans-membrane transport of β-carotene. In addition, they also directly or indirectly correlated with the β-carotene metabolism associated genes such as BCO2, BCMO1 and PPARCG1A. Further research may focus on the relevant molecular regulatory mechanisms, so as to provide a theoretical basis for the preparation of β-carotene containing feed and the targeted regulation of beef fat color.

[Objective] This study was conducted to explore the effects of dietary supplementation of plant essential oils prepared with different processes on growth performance, intestinal digestive enzyme activity and serum immunoglobulin level of weaned piglets.[Method]A total of 198 heads of 21-day-old Duroc × Landrace × Yorkshire （DLY） healthy weaned piglets with an average weight of （5.687±0.761） kg were randomly assigned into 3 groups, with 11 replicates in each group and 6 piglets in each replicate. The control group fed a basal diet. The two experimental groups fed the same basal diet in which 300 g/t of a micro-encapsulated and control-released plant essential oil （MECR-PEO） or a mixed plant essential oil （M-PEO） were supplemented, respectively. The feeding experiment lasted for 21 days. The average daily feed intake, average daily weight gain and feed to weight gain ratio of the experimental piglets at 22-28 days, 29-35 days and 36-42 days of age, as well as the diarrhea rate at 22-42 days of age were calculated. On the 21^st day of the feeding experiment, the duodenal chyme was collected, and the activities of intestinal trypsin, amylase and lipase were measured. At the end of the feeding experiment, blood samples were collected with serum prepared. ELISA assay was used to detect the serum levels of IgG, IgM and IgA. [Result] At 22-28 days and 29-35 days of age, the dietary supplementation of the two types of plant essential oils had the trends of increasing the average daily weight gain and average daily feed intake, as well as reducing the feed to weight gain ratio （P>0.05） compared with the control group. At 36-42 days of age, the piglets received the dietary supplementation of MECR-PEO had significantly （P<0.05） higher average daily weight gain and significantly （P<0.05） lower feed to weight gain ratio than those in the control group; the piglets received the dietary supplementation of M-PEO had higher average daily weight gain and average daily feed intake （P>0.05）, as well as lower feed to weight gain ratio than those in the control group （P>0.05）. At 22-42 days of age, the diarrhea rates of the piglets in both plant essential oil supplementation groups were significantly （P<0.05） reduced compared with the control group. The MECR-PEO supplementation group exhibited a better performance, with a decrease in diarrhea rate of 67.79% compared to the control group. Piglets in the MECR-PEO supplementation group had significantly （P<0.05） higher activities of duodenal trypsin, amylase and lipase in comparison to those in the control group, and had significantly （P<0.05） higher lipase activity in comparison to those in the M-PEO supplementation group. Significantly （P<0.05） higher duodenal trypsin activity was observed in the M-PEO supplementation group compared to the control group. Significantly （P<0.05） elevated serum levels of IgG and IgM in the MECR-PEO supplementation group was found compared with the control group, and significantly （P<0.05） elevated serum IgM level in the M-PEO supplementation group was found compared with the control group. [Conclusion] Dietary supplementation of MECR-PEO and M-PEO had positive effects on improving growth performance as well as enhancing intestinal digestive enzyme activity and serum immunoglobulin level in weaned piglets. The effects of MECR-PEO were better.

[Objective] To investigate the effects of different levels of grape seed pomace （GSP） replacing partial corn and cottonseed meal in concentrate supplements on in vitro rumen gas production, in vitro nutrients digestibility, fermentation parameters, and growth performance of Simmental cattle. [Method] Using the rumen simulation technique, corn and cottonseed meal in concentrate supplements were partially replaced by GSP at proportions of 4%, 8%, 12% and 16%, respectively. The in vitro gas production, fermentation parameters, in vitro nutrients digestibility of each groups were measured, and the growth performance of the cattle fed with diets in which corn and cottonseed meal were partially replaced by different levels of GSP were evaluated. [Result] The cumulative gas production increased as the in vitro fermentation period extended. The 12% GSP group produced the most gas, and there was no significant （P>0.05） difference in total gas production across the different groups at 72 h of fermentation. There were no significant （P>0.05) differences in pH value, NH₃-N concentration, or bacterial protein content in the artificial rumen fluid between the different groups after gas production. The concentrations of volatile fatty acids increased significantly （P<0.05) in the experimental groups. The digestibility of dry matter was the lowest in the 16% GSP group. The digestibility of crude protein in the control group was significantly （P<0.05) higher than that in the experimental groups. The digestibility of neutral detergent fiber in the control group and the 4% GSP group was significantly （P<0.05) higher than that in the other three groups. The digestibility of acid detergent fiber in the control group and the 12% GSP group was significantly （P<0.05) higher than that in the other three groups. The average daily gain of the cattle in the 4% and the 8% GSP groups was 170 g/d and 140 g/d higher than that of the control group, respectively. [Conclusion] Replacement of partial corn and cottonseed meal in concentrate supplements with GSP improved the concentrations of volatile fatty acids in artificial rumen fluid. Replacing proportions of 4% or 8% of GSP increased the daily gain and boosted the rumen fermentation of beef cattle, which was conducive to improve the growth performance.

[Objective] The aim of this study was to optimize the ultrasonic extraction process parameters of crude fat in feed. [Method] Using the grass carp expanded compound feed as experimental material, a single factor experiment design was adopted to investigate and analyze the effects of 4 factors （liquid to material ratio, soaking time, ultrasonic duration and ultrasonic frequency） at different levels on the determination of crude fat content in feed. In addition to the single factor experiments, a 4-factor and 3-level L9 （3⁴） orthogonal experiment was conducted to optimize the ultrasonic extraction process parameters of crude fat in feed. The crude fat content of grass carp expanded compound feed was measured using the optimized ultrasonic extraction process, and the results were compared to those obtained using the Soxhlet extraction method. The process was repeated 6 times to verify the optimal ultrasonic extraction process parameters. Following the determination of the ultrasonic extraction process parameters, the crude fat contents of 13 different feed samples were measured using both the ultrasonic extraction method and the Soxhlet extraction method with 6 repeated tests. The differences in crude fat content of the feed raw materials and common animal feed products between the two extraction methods were then analyzed and compared. [Result] The factors affecting the determination of crude fat content in feed was in the order of ultrasonic frequency>liquid to material ratio>ultrasonic duration>soaking time. The optimal ultrasonic extraction process parameters were liquid to material ratio of 37.5 mL/g, soaking for 0 min, ultrasonic duration for 30 min, and ultrasonic extraction twice. The crude fat content of grass carp expanded compound feed determined by the optimal ultrasonic extraction process was 4.76% （n=6）, whereas that determined by the Soxhlet extraction method was 4.77% （n=6）, proving that the ultrasonic extraction process was stable and feasible. The differences in crude fat content determination results of 13 different feed samples between the ultrasonic extraction method and the Soxhlet extraction method were not significant （P>0.05）. [Conclusion] The optimal process parameters for ultrasonic extraction of crude fat in feed determined in this study were stable and feasible.

[Objective] The aims of the present study were to isolate and screen cellulolytic bacteria derived from spent Flammulina velutipes substrate, to assess their biological characteristics and cellulolytic enzyme activities, so as to provide technical supports for the feed utilization of spent mushroom substrate resources. [Method] Spent Flammulina velutipes substrate samples were inoculated using plate dilution coating method. The cellulolytic bacteria were then isolated and cultured on nitrate cellulose sodium medium. The cellulolytic abilities of the isolated strains were preliminarily analyzed using Congo red medium. Candidate strains were selected through 16S rDNA sequencing analysis and biosafety prediction, followed by physiological and biochemical characteristics analysis, growth curve determination at different temperatures, and dynamic analysis of cellulolytic enzyme activities. [Result] A total of 30 independent colonies were isolated after screening culture with nitrate cellulose sodium medium. All of the strains formed clear transparent circles on Congo red medium, and some strains had strong cellulolytic abilities. The 16S rDNA sequencing analysis showed that the 30 isolated strains were identified as belonging to 9 bacterial species, including Pseudomonas koreensis, Advenella mimigardefordensis, Serratia rubidaea, and so on. Taking into account both biosafety prediction and the preliminary cellulolytic abilities screening results, Pseudomonas koreensis （JK-32）, Adrenella mimigardefordensis （JK-52）, Serratia rubidaea （JK-56）, Staphylococcus equiorum （JK-57）, Staphylococcus saprophytics （JK-62） and Serratia marcescens （JK-66） were selected as candidate strains for subsequent experiments. Physiological and biochemical characteristics analysis showed that all of the 6 candidate strains were determined as positive for contact enzyme activity test, and negative for methyl red test and diacetyl test. The growth of JK-62 strain was less affected by temperature, and the growth rate and final bacterial concentration performed better among all the candidate strains. Under the low cultivation temperatures （28-34 ℃）, the growth rate and final bacterial concentration of JK-56 strain were lower than the other candidate strains, while when the cultivation temperature increased to 40 ℃, its growth rate was similar to that of the other candidate strains and the final bacterial concentration was higher. On the 1^st to 7^th days of cultivation, the endoglucanase activity of JK-56 strain was the highest among all the candidate strains. On the 2^nd, 4^th, and 5^th days of cultivation, the endoglucanase activity of JK-66 strain was significantly （P<0.05） higher than that of the CK. The exoglucanase activity of JK-66 strain was higher among the candidate strains and was significantly （P<0.05） higher than that of the CK at different detection time points. On the 2^nd to 4^th days of cultivation, the exoglucanase activity of JK-56 strain was significantly （P<0.05） higher than that of the CK. The β-glucosidase activity of JK-66 strain was higher among the candidate strains. On the 3^rd to 7^th days of cultivation, the β-glucosidase activity of JK-56 strain was next to JK-62 and JK-66 strains among the candidate strains. On the 2^nd to 5^th days of cultivation, the filter paper enzyme activity of JK-56 strain was the highest among the candidate strains. On the 5^th day of cultivation, it was significantly （P<0.05） higher than that of the CK. During this period, the filter paper enzyme activity of JK-66 strain was also at a high level. [Conclusion] Serratia rubidaea JK-56 and Serratia marcescens JK-66 strains had high overall levels of cellulolytic enzyme activities, and prominent endoglucanase and exoglucanase activities, which could be used in combination with strains exhibiting strong β-glucosidase activity for the development and utilization of spent Flammulina velutipes substrate.

[Objective] This study aimed to assess the effects of gossypol on growth performance, serum antioxidant capacity, and renal pathological morphology of male broilers at different growth stages, so as to accumulate basic experimental data for the rational application of cotton seed meal in broiler breeding. [Method] A total of 48 healthy 1-day-old Liangfenghua male broilers from the same batch were selected and randomly allocated to 4 groups according to the principle of similar body weight, including a control group （C）, a low-dose group （L）, a medium-dose group （M）, and a high-dose group （H）. Each group had 4 replicates, with 3 broilers per replicate. The experimental broilers in different groups fed the same basal diet. In addition, the broilers in L, M and H group were orally administered 100, 150 and 200 mg/（kg·BW） gossypol once a day until 20-day-old, for a total of 20 days, respectively, while those in C group were orally given distilled water. During the experiment, the feed intake and weight gain of the broilers in each group were recorded, and the feed to weight gain ratio at different growth stages were calculated. Blood samples were collected at 6, 11, 16 and 21 days of age, and the serum activities of catalase （CAT） and glutathione peroxidase （GSH-Px） were measured. Kidney tissue samples were collected at 21 days of age, with HE staining sections prepared, and changes in renal histopathology observed. [Result] At 1-15 days of age, the feed to weight gain ratios of L, M and H groups were extremely significantly （P<0.01） higher than that of C group; at 6-15 days of age, the feed to weight gain ratio of M group was extremely significantly （P<0.01） higher than that of L group; at 16-20 days of age, the feed to weight gain ratios of L and H groups were extremely significantly （P<0.01） higher than that of C group, while that of M group had negative increase. At 6-21 days of age, the serum activities of CAT and GSH-Px in C group showed upward trends, while those in L, M and H groups all showed downward trends; at 11 days of age, the serum activities of CAT and GSH-Px in L group were significantly （P<0.05） lower than those in C group, while the serum activity of GSH-Px in M and H groups was extremely significantly （P<0.01） lower than that in C group; at 16 and 21 days of age, the serum activities of CAT and GSH-Px in L, M and H groups were all extremely significantly （P<0.01） lower than those in C group; at 21 days of age, the serum activity of GSH-Px in M group was extremely significantly （P<0.01） lower than that in L group. Pathological histology observations showed that the renal glomeruli of the broilers given gossypol by gavage were swollen, the renal capsule space became narrower, and the renal tubules were necrotic.The degree of renal tissue damage was M group>H group>L group. [Conclusion] Starting from 1-day-old, feeding male broilers with doses of 100, 150 and 200 mg/（kg·BW） of gossypol for 20 consecutive days by gavage reduced growth performance, decreased serum antioxidant capacity, and caused kidney damage. With the prolongation of gossypol feeding time, the above affects were the most obvious at the dose of 150 mg/（kg·BW）.

[Objective] This study aimed to assess the research status, hotspots and trends of dairy industry development in China by bibliometric and visual analyses, so as to provide data supports for the domestic dairy industry development. [Method] China National Knowledge Infrastructure （CNKI） Database was used as the data source to retrieve literature in the field of dairy industry development research in China from 1992 to 2023. The knowledge graphs for the dairy industry development research field was created using the visualization analysis tool CiteSpace. In combination with bibliometric methods, the research status, hotspots and theme evolution in this field were then analyzed. [Result] According to the retrieve criteria, a total of 739 journal articles were included, with the highest annual publication volume in 2002, reaching 60 articles. The top three authors by publication quantity were LIU Yuman （17 articles）, LI Shengli （15 articles） and LIU Fang （15 articles）, and the top three institutions were Rural Development Institute of Chinese Academy of Social Sciences （19 articles）, Agricultural Information Institute of Chinese Academy of Agricultural Sciences （18 articles） and College of Economics and Management of Northeast Agricultural University （17 articles）. The dairy industry development research filed had formed a relatively tight and mature collaboration network. The institutions such as Agricultural Information Institute of Chinese Academy of Agricultural Sciences, College of Animal Science and Technology of China Agricultural University, Rural Development Institute of Chinese Academy of Social Sciences, Institute of Animal Science of Chinese Academy of Agricultural Sciences had higher cooperation densities and tighter connections with each other. Dairy industry and dairy industry development were the research hotspots in this field. Keywords such as dairy industry development, milk source base, dairy factory, dairy cattle industry and milk yield emerged earlier, while low-carbon development, regulatory approach and smart farming emerged recently. [Conclusion] The research hotspots on the theme of dairy industry development were dynamically changing, with high collaboration densities among researchers and institutions. There was regional heterogeneity in the distribution of collaboration networks. Low-carbon development and smart farming may be the focus of future research.

[Objective] This study was conducted to explore the optimal plant spacing and row spacing for seed production of Bothriochloa ischaemum.[Method] Using Bothriochloa ischaemum ′Taihang′ seeds as the experimental materials and a two-factor split zone experiment design, four plant spacing levels （R₁=30 cm, R₂=45 cm, R₃=60 cm, R₄=75 cm） and four row spacing levels （L₁=30 cm, L₂=45 cm, L₃=60 cm, L₄=75 cm） were set up to assess the effects of different plant spacing and row spacing combinations on seed yield and its components of Bothriochloa ischaemum.[Result]Plant spacing and row spacing had extremely significant （P<0.01） interactions on the reproductive branch number, inflorescence length, plant height and shattering rate. The interactions between plant spacing and row spacing had extremely significant （P<0.01） effects on the actual seed yield of Bothriochloa ischaemum. Correlation analysis demonstrated that plant spacing was significantly （P<0.05） positively correlated with the reproductive branch number, spikelet number, theoretical seed yield and actual seed yield, and significantly （P<0.05） negatively correlated with the inflorescence length; the row spacing was significantly （P<0.05） positively correlated with the reproductive branch number, spikelet number, thousand grain weight, theoretical seed yield and actual seed yield, and significantly （P<0.05） negatively correlated with the inflorescence length. Principal component analysis showed that the cumulative contribution rate of the first two principal components was 81.946%. The main traits determining the first common factor were reproductive branch number, spikelet number, inflorescence length, shattering rate, thousand grain weight, theoretical seed yield and actual seed yield. The contribution rate of the second common factor was 20.994%. The comprehensive evaluation of yield indicators revealed that R₃L₃ （60 cm × 60 cm） had the highest score of 5.039.[Conclusion]To achieve the highest seed yield of Bothriochloa ischaemum, the optimal plant spacing and row spacing were 60 cm for both.

[Objective] This study was conducted to assess the effects of dietary supplementation of soybean isoflavones and bile acids on production performance and serum physiological and biochemical indexes of green-shell laying hens. [Method] A total of 72 370-day-old green-shell laying hens were selected and randomly assigned into a control group or an experimental group, with 4 replicates in each group and 9 hens in each replicate. The control group were fed with a corn-soybean meal basal diet, while the experimental group received the same basal diet supplemented with 12.5 mg/kg soybean isoflavones and 60 mg/kg bile acids. The whole feeding experiment was consist of a 7-day preliminary trial and a 105-day formal trial. The feed intake, egg production and egg weight of each laying hen replicate during the experiment were recorded, and the average feed intake, feed to egg ratio and egg production rate were calculated. At the end of the experiment, egg samples were collected to measure egg quality indexes; blood samples were collected to prepare serum, and the serum physiological and biochemical indexes were measured. [Result] Compared with the control group, the average feed intake and egg production rate of the experimental group increased by 11.80% and 10.64%, respectively, with significant （P<0.05） differences. There were no significant （P>0.05） differences in the feed to egg ratio, egg shape index, egg weight, relative weight of eggshell, and relative weight of egg yolk between the experimental group and the control group, while there was an increasing trend in egg weight and relative weight of eggshell in the experimental group. The serum content of acetylcholinesterase （AChE） in the experimental group increased by 32.45% compared to that of the control group, with significant （P<0.05） difference. No significant （P>0.05) differences in serum contents of total protein （TP）, albumin （ALb）, glutamic pyruvic transaminase （GPT）, glutamic oxalacetic transaminase （GOT）, follicle-stimulating hormone （FSH）, and luteinizing hormone （LH） were observed between the experimental group and the control group, while increasing trends in serum contents of TP, ALb, FSH and LH as well as decreasing trends in those of GPT and GOT were observed in the experimental group. [Conclusion] Dietary supplementation of 12.5 mg/kg soybean isoflavones and 60 mg/kg bile acids for green-shell laying hens in the middle and late laying period improved the production performance and serum biochemical indexes.

[Objective] This study aimed to investigate the effects of crossbreeding of Australian White sheep as paternal parents and Hulun Buir sheep as maternal parents on reproductive performance and reproductive hormone secretion during gestation period of ewes. [Method] A total of 392 Hulun Buir ewes were selected and randomly assigned into an experimental group or a control group according to the ram breeds. For the ewes in the experimental group （n=139）, Australian White sheep （n=7） were served as the breeding ram, while for those in the control group （n=253） , Hulun Buir sheep （n=13） were served as the breeding ram. After delivery, the reproductive performance indicators such as conception rate, miscarriage rate and twinning rate of the ewes in the two groups, as well as the birth weights of the lambs produced by the ewes in the two groups were statistically compared. Eight ewes were selected from each group, and blood samples were collected at mid-gestation period （60 d gestation）, late-gestation period （90 d gestation） and 10 d before the expected date of lambing, respectively. The serum levels of follicle-stimulating hormone （FSH）, luteinizing hormone （LH）, progesterone （P₄） and estradiol （E₂） were measured with ELISA kits.[Result] The ewes in the experimental group had significantly （P<0.05） lower conception rate and actual delivery rate, significantly （P<0.05） higher miscarriage rate, and extremely significantly （P<0.01） higher twinning rate compared with those in the control group. No significant （P>0.05） difference in lamb survival rate between the experimental group and the control group was observed. There were no significant （P>0.05） differences in the lamb birth weight, single-lamb birth weight and twin-lamb birth weight between the experimental group and the control group. At each observed time points during gestation period, the serum levels of FSH, LH, P₄ and E₂ of the experimental group ewes had no significant （P>0.05） differences with those of the control group ewes. For the ewes in the control group, there were no significant （P>0.05） differences in the serum levels of LH, FSH and E₂ among the three observed time points during gestation period, while the serum level of P₄ at 10 d before the expected date of lambing was significantly （P<0.05） higher than that at the mid- and late-gestation period. For the ewes in the experimental group, the serum level of E₂ at the late-gestation period was significantly （P<0.05） higher than that at the mid-gestation period and 10 d before the expected date of lambing; the serum level of E₂ at the mid-gestation period was significantly （P<0.05） higher than that at 10 d before the expected date of lambing; the serum level of P₄ at the late-gestation period and 10 d before the expected date of lambing was significantly （P<0.05） higher than that at the mid-gestation period. [Conclusion] Crossbreeding of Australian White sheep as paternal parents and Hulun Buir sheep significantly elevated the twining rate and thus improved the reproductive efficiency of ewes, indicating that Australian White sheep as paternal parents had heterosis in improving the reproductive performance of Hulun Buir sheep.

[Objective] This study was conducted to assess the mechanism underlying the response of plant functional groups in desert steppe to different grazing intensities, and to provide bases for the rational utilization of desert steppe. [Method] The desert steppe distributed in Sonid Right Banner, Xilin Gol League, Inner Mongolia was chosen as the research object. Three grazing intensity treatments were set up, including a non-grazing （NG） treatment, a moderate grazing （MG） treatment and a heavy grazing （HG） treatment. Each treatment had 3 replications, with a total of 9 experimental plots. The stocking rates of the NG, MG and HG treatments were 0, 1.92 and 3.08 sheep unit/（hm² · year）, respectively, and the corresponding actual number of grazing sheep was 0, 5 and 8, respectively. From 2018 to 2020, the density, coverage, height and above ground biomass of the plant functional groups in the desert steppe were annually surveyed in mid August. The differences in the quantitative characteristics of the plant functional groups under varied grazing intensities were statistically compared. Furthermore, the grey correlation analysis was conducted between plant functional group and community under different grazing intensities. [Result] The highest number of plant species was observed in MG treatment, followed by NG treatment and HG treatment, which were 27, 25 and 19 species, respectively. Grazing significantly （P<0.05） increased the density of perennial forbs and decreased the density proportion of perennial grasses. The coverage of perennial grasses, annuals and biennials, as well as shrubs and semi-shrubs gradually reduced with the increasing grazing intensities. Grazing significantly （P<0.05） reduced the coverage of shrubs and semi-shrubs. The coverage proportion of perennial grasses as well as annuals and biennials gradually decreased with the increasing grazing intensities, while that of perennial forbs elevated with the increasing grazing intensities. Grazing significantly （P<0.05） reduced the height of perennial forbs as well as shrubs and semi-shrubs, decreased the height proportion of shrubs and semi-shrubs as well as perennial forbs, and increased the height proportion of perennial grasses as well as annuals and biennials. Grazing significantly （P<0.05） reduced the above ground biomass of shrubs and semi-shrubs. Heavy grazing significantly （P<0.05） reduced the above ground biomass of all plant functional groups. Grazing increased the above ground biomass proportion of annuals and biennials as well as perennial forbs, and reduced that of shrubs and semi-shrubs as well as perennial grasses. In the NG treatment, perennial grasses as well as annuals and biennials were the functional groups that had the highest correlation with the community, both with correlation degrees of 0.76. In the MG treatment, the functional group showing the highest correlation with the community was perennial forbs, with a correlation degree of 0.77, followed by annuals and biennials, with a correlation degree of 0.75. In the HG treatment, the functional group exhibiting the highest correlation with the community was perennial forbs, with a correlation degree of 0.80, followed by annuals and biennials, with a correlation degree of 0.67. [Conclusion] Moderate grazing enriched the plant species in the desert steppe. Long-term heavy grazing significantly reduced the above ground biomass of all plant functional groups. Long-term grazing reduced the dominance of perennial grasses and increased that of perennial forbs in the community, converting the functional groups with the highest correlation with the community from perennial grasses as well as annuals and biennials to perennial forbs as well as annuals and biennials.

[Objective] This study aimed to analyze the structure and function of African swine fever virus （ASFV） pI215L protein. [Method] A total of 29 pI215L gene sequences of different ASFV strains were downloaded from the African Swine Fever Virus Database （ASFVdb）. Bioinformatics tools were used to analyze the homology and genetic evolution of pI215L gene of different ASFV strains, and to predict the physicochemical properties, secondary structure, linear epitope, and three-dimensional spatial location of pI215L protein. [Result] The pI215L gene sequences had high homology among different ASFV strains. The pI215L protein was unstable and hydrophilic. Its secondary structure mainly contained four forms, including α-helix, extend strand, β-turn, and random coil, and had a domain of E2 Ubiqutin-conjugating enzyme. A total of 16 peptide fragments were potential linear epitopes. SWISS-MODEL was used to complete homology modeling of the tertiary structure of pI215L protein, and its homology with 6NYO.1 （ubiquitin-conjugating enzyme E2 R2 and ubiquitin） in the PDB database was 46.06%. The PyMOL software was used to predict the conformational epitopes of pI215L protein to accurately locate the distribution of the predicted three-dimensional spatial position of the epitopes in the model. [Conclusion] Our results provided references for unravelling the structure and function of pI215L protein, as well as developing vaccines and drugs for prevention and control of ASFV.

[Objective] This study was conducted to characterize the microbial community diversities in pig house environments, to understand the structural differences of bacterial communities in different types of pig house environments, and to identify the potentially pathogenic bacterial genera. [Method] Environmental microbial samples were collected from pregnant sow houses, nursery pig houses and farrowing houses in a large-scale pig farm using air sedimentation method. Three houses were sampled for each type of pig house, with a total of 9 samples. Using Illumina Miseq technology, the high-throughput sequencing was performed targeting on the V3-V4 variant region of bacterial 16S rDNA. The sequencing data were analyzed by QIIME2 software to compare the composition of microbial communities in different types of pig house environments. [Result] At the similarity threshold of 97%, a total of 29 126 OTUs were obtained from the 9 samples, covering 31 phyla, 66 classes, 160 orders, 320 families, 899 genera and 1 831 species of bacteria. The Chao1 index, Shannon index and phylogenetic diversity index of the farrowing houses and nursery pig houses were generally higher than those of the pregnant sow houses. Proteobacteria, Bacteroidota, Firmicutes and Actinobacteriota were the four dominant bacterial groups at the phylum level in the pig house environments. The relative abundance of Proteobacteria was the highest in all three types of pig houses, while the relative abundance of Firmicutes, Actinobacteria and Bacteroidetes varied greatly among different types of pig houses. Acinetobacter, Corynebacterium and Stenotrophomonas were the genera with the highest relative abundance in farrowing houses, pregnant sow houses and nursery pig houses, respectively. There were multiple genera of bacteria with potential pathogenicity to animals, such as Helcococcus, Streptococcus, Legionella and Serratia, in the air of pig houses. [Conclusion] The pig house environments were rich in microbial community diversities. Farrowing houses and nursery pig houses had higher bacterial diversity, evolutionary diversity and abundance than the pregnant sow houses. The potentially pathogenic bacteria found in this study provided references for the selection of disinfection drugs used in pig house environments.

[Objective] This study was conducted to assess the effects of different addition levels of compound bacterial inoculants on nutritional value and fermentation quality of Pennisetum purpureum × P. glaucum cv. Reyan No. 4 silage. [Method] Using Pennisetum purpureum × P. glaucum cv. Reyan No. 4 with adjusted water content at around 60% as experiment material, one control （CK group） and four test groups were set up based on single factor experiment design. Each group of Pennisetum purpureum × P. glaucum cv. Reyan No. 4 weighed 90 kg. The CK group did not have any bacteria addition, while the test groups had compound bacterial inoculant additions consisting of different ratios of five silage fermentation bacteria （Lactobacillus + Saccharomyces + Bacillus subtilis + Bacillus licheniformis + Lactobacillus planturum）. The addition levels of the compound bacterial inoculants for the test groups Ⅰ to Ⅳ were 10 g+15 g+10 g+10 g+5 g, 10 g+15 g+15 g+15 g+10 g, 10 g+15 g+20 g+20 g+15 g, and 10 g+15 g+25 g+25 g+20 g, respectively. Each group was repeated three times. After 30 d of silage fermentation, the quality sensory evaluation, nutrient composition analysis, and fermentation quality determination of the silage fermentation products in each group were carried out immediately after opening the bags. [Result] The silage in the test groups Ⅰ and Ⅲ had better quality sensory evaluation with superior grade. There was no significant （P>0.05） difference in dry matter content among the different groups. The crude protein content in the test group Ⅰ was significantly （P<0.05） higher than that in the test groups Ⅱ and Ⅲ. The starch content in the test groups Ⅰ and Ⅱ was significantly （P<0.05） higher than that in the CK group as well as the test groups Ⅲ and Ⅳ. The crude ash content in the test group Ⅲ was the highest, which was significantly （P<0.05） higher than that in the CK group and the other test groups. The four test groups all had significantly （P<0.05） higher water-soluble carbohydrate content than the CK group, and the highest value was observed in the test group Ⅰ. There was no significant （P>0.05） difference in crude fat content among the different groups. The highest total fatty acid content was found in the test group Ⅲ, showing a statistically significant （P<0.05） difference compared with the CK group. The neutral detergent fiber content in the four test groups was all significantly （P<0.05） lower than that in the CK group. The acidic detergent fiber content in the test groups Ⅰ and Ⅱ was significantly （P<0.05） lower than that in the test group Ⅳ, while that in the test groups Ⅲ and Ⅳ was significantly （P<0.05） higher in comparison to the CK group. The lignan content in the test group Ⅱ was significantly （P<0.05） lower than that in the CK group. Among the four test groups, the 30 h neutral detergent fiber digestion rate in the test group Ⅰ was the highest, while that in the test groups Ⅱ, Ⅲ, and Ⅳ was significantly （P<0.05） lower compared with the CK group. No significant （P>0.05） differences in the contents of calcium, phosphorus, magnesium, potassium and sulfur elements as well as chloride ion were found among the different groups. There were no significant （P>0.05） differences in the contents of lactic acid and acetic acid among the different groups. The test group Ⅰ had the highest lactic acid content, while the test group Ⅳ had the highest acetic acid content. The butyric acid content in test groups Ⅰ, Ⅱ, and Ⅲ was significantly （P<0.05） lower than that in the CK group. The ammonia nitrogen content in the test group Ⅲ was significantly （P<0.05） lower than that in the CK group. [Conclusion] The addition of the compound bacterial inoculant consisting of 10 g of Lactobacillus, 15 g of Saccharomyces, 10 g of Bacillus subtilis, 10 g of Bacillus licheniformis, and 5 g of Lactobacillus planturum to 90 kg Pennisetum purpureum × P. glaucum cv. Reyan No. 4 with the adjusted water content around 60% was favourable to improve the nutritional value and fermentation quality of the silage.

[Objective] This study was conducted to characterize the expression pattern of antioxidant enzymes in sheep antral ovarian follicles with different diameters, so as to provide references for clarifying the regulatory mechanism of antioxidant function in ovarian follicles. [Method] The follicular fluids were sampled from sheep antral ovarian follicles with different diameters （large antra ≥ 6.0 mm, medium antra 2.0-6.0 mm, small antra ≤ 2.0 mm). The contents of reactive oxygen species （ROS） and total antioxidant capacity （TAC）, as well as the activities of superoxide dismutase （SOD）, catalase （CAT）, glutathione peroxidase （GPX） and peroxidase （PRDX） were tested using the commercially available reagent kits. Real time fluorescence quantitative PCR （qPCR） assay was used to detect the relative mRNA expression levels of Cu/Zn-SOD, CAT, GPX3 and PRDX6 genes in the theca cells, mural granulosa cells and cumulus cells of small, medium and large antral ovarian follicles. [Result] There were no significant （P>0.05） differences in the contents of TAC and ROS in the follicular fluids of antral ovarian follicles with different diameters. The activities of SOD, GPX and PRDX in the follicular fluids decreased with the increase of ovarian follicle diameters. The small antral ovarian follicles had extremely significantly （P<0.01） higher activities of SOD, GPX and PRDX in the follicular fluids compared to the large antral ovarian follicles. The CAT activity in the follicular fluids elevated with the increase of ovarian follicle diameters. The large and medium antral ovarian follicles had extremely significantly （P<0.01） higher CAT activities in the follicular fluids than the small antral ovarian follicles. The relative mRNA expression levels of Cu/Zn-SOD, GPX3 and PRDX6 genes in the theca cells and mural granulosa cells of the small antral ovarian follicles were extremely significantly （P<0.01） higher than those of the medium and large antral ovarian follicles, while the relative mRNA expression levels of Cu/Zn-SOD, GPX3 and PRDX6 genes in the cumulus cells of the medium antral ovarian follicles were extremely significantly （P<0.01） higher than those of the small and large antral ovarian follicles. The large antral ovarian follicles had extremely significantly （P<0.01） higher relative mRNA expression levels of CAT gene in the theca cells and mural granulosa cells than the small and medium antral ovarian follicles, while the large and medium antral ovarian follicles had extremely significantly （P<0.01） higher relative mRNA expression levels of CAT gene in the cumulus cells than the small antral ovarian follicles. [Conclusion] There was no significant variations in contents of TAC and ROS in sheep antral ovarian follicles with different diameters, but the gene expression levels and the activities of antioxidant enzymes of SOD, CAT, GPX and PRDX in ovarian follicles with different diameters exhibited spatial specificity, indicating that the regulation of antioxidant function in sheep antral ovarian follicles was a synergistic process of multiple factors.

[Objective] The present study was conducted to assess the correlations between serum hormone levels and lactation performance in Alagxa Bactrian camels. [Method] A total of 65 Alagxa Bactrian camels with similar body conditions and parities in the early lactation stage were selected, and their serum hormone levels （estradiol, estriol, estrone, follicle-stimulating hormone, luteinizing hormone, progesterone, prolactin, growth hormone, cortisol, 5-hydroxytryptamine, epinephrine, norepinephrine, insulin, glucagon, leptin） as well as the lactation performance indicators （milk yield, milk protein rate, milk fat rate, lactose rate, ash content） were determined. Canonical correlation analysis between serum hormone levels and lactation performance was carried out: using lactation performance indicators as the X group variables, with V being the corresponding comprehensive variable; using serum hormone levels as the Y group variables, with W being the corresponding comprehensive variable; the overall correlation between the two groups of indicators were reflected by the correlation between the two comprehensive variables, and the correlations between serum hormone levels and various indicators of lactation performance were explored. [Result] In the X group of lactation performance indicators, the variation degree in the milk yield was the highest, followed by milk fat rate, while the coefficients of variation in lactose rate, ash content and milk protein rate were relatively small. In the Y group of serum hormone level indicators, progesterone had the highest coefficient of variation, followed by estradiol, luteinizing hormone, norepinephrine, follicle-stimulating hormone, 5-hydroxytryptamine, cortisol, estrone, prolactin, epinephrine, insulin, estriol, growth hormone, leptin and glucagon. The correlation analysis among the internal variables of serum hormone levels showed that serum levels of estriol were significantly positively correlated with those of estrone （r=0.88, P<0.001）, luteinizing hormone （r=0.70, P<0.001） and prolactin （r=0.59, P<0.001）. The canonical correlation analysis between lactation performance and serum hormone levels indicated strong correlation between milk protein rate and serum level of estriol. [Conclusion] The milk protein rate in the early lactation stage of Alagxa Bactrian camels is correlated with serum hormone levels of estriol, estrone, luteinizing hormone and prolactin.

[Objective] The aim of this study was to understand the infection status and molecular genetic characteristics of Echinococcus granulosus （E. granulosus） derived from sheep in some large-scale abattoirs in Xinjiang Uygur Autonomous Region, China. [Method] A total of 96 cyst samples identified as E. granulosus by macroscopic observation were collected from the liver tissues of sheep in abattoirs. Following genomic DNA extraction, PCR amplification and sequencing were performed based on the cox1 and nad1 gene loci of E. granulosus. Sequence alignment was carried out to identify the genotype. The genetic evolution tree was constructed to analyze the molecular genetic characteristics. [Result] At the cox1 gene locus, a total of 81 samples were positive in PCR amplification （84.37%, 81/96）. Sequence analysis identified that all positive samples were G1 genotype of E. granulosus （n=81）, with 15 haplotypes （Hap_1-15） presented. At the nad1 gene locus, there were 67 PCR positive samples （69.79%, 67/96）. Two genotypes, G1 genotype （n=66） and G3 genotype （n=1） of E. granulosus, were identified through sequence analysis,with 19 haplotypes （Hap_1-19） presented. According to the phylogenetic analysis, the G1 and G3 genotypes of E. granulosus obtained in this study were in the same evolutionary branches as their counterparts of E. granulosus derived from the multiple host sources reported in China and abroad. [Conclusion] The E. granulosus derived from sheep in some parts of Xinjiang showed genetic diversity. Our results provide fundamental data for the prevention and control of echinocococosis in sheep in this region.

[Objective] To assess the effects of dietary supplementation of active dry yeast （ADY） on feed digestibility and daily gain of fattening Simmental cattle. [Method] A total of 30 Simmental cattle were randomly split into three groups. Group A was the control, groups B and C were the experimental groups. Group A was fed with the basal diet, and groups B and C were fed with the basal diets supplemented with NO.1 ADY （10 g/d） and NO.2 ADY （10 g/d） twice daily, respectively. The pre-feeding phase was 5 days followed by 28 days formal trial period. Fecal separation sieve was used to assess the feed digestibility of the experimental fattening cattle, and the daily gain was monitored. [Result] On day 21 of the experiment, the proportion of up-level fecal sieve residue in group C was significantly （P<0.05） lower than that in group A. On the 28^th day of the experiment, group C had lower proportion of middle-level fecal sieve residue than groups A and B, and was significantly （P<0.05） lower than that on the 7^th, 14^th, and 21^st days of the experiment. The proportion of lower-level fecal sieve residue in group C was the highest on the 28^th day of the experiment, and was significantly （P<0.05） higher than that on the 7^th and 14^th days of the experiment. The average daily gain of the two experimental groups was higher than that of the control group. The average daily gain of group C was significantly （P<0.05） higher than that of group A and group B. [Conclusion] Dietary supplementation of NO.1 and NO.2 ADY increased the daily gain of fattening Simmental cattle and enhanced the feed digestibility to a certain degree. NO.2 ADY exhibited a better effect.

[Objective] The aim of the present study was to characterize the antimicrobial resistance profile as well as the prevalence of CTX-M gene and virulence genes of the Escherichia coli （E. coli） strains derived from cattle in Ta′e reclamation area, Xinjiang Uygur Autonomous Region. [Method] A total of 16 fecal samples of cattle with diarrhea were collected from a cattle farm in Ta′e reclamation area. The selective culture, Gram staining and microscopy, and 16S rDNA PCR amplification and sequencing were used to isolate and identify the E. coli strains. The PCR assay was used for the molecular typing （phylogenetic group and lipopolysaccharide core type） as well as the detection of antimicrobial resistance genes, CTX-M gene subtypes and virulence genes of the E. coli isolates. The K-B disk diffusion method as well as the CTX and TCL dual disk diffusion method were utilized for antimicrobial sensitivity test and ESBLs-producing E. coli identification, respectively. The biofilm formation ability of the E. coli isolates were semi-quantitatively analyzed using crystal violet staining method.[Result] Based on the colony growth feature, Gram staining characteristic and 16S rDNA sequencing result, a total of 16 E. coli strains were isolated and identified from the 16 fecal samples of the diarrhoeal cattle, with a separation rate of 100%. Most of the E. coli isolates belonged to the phylogenetic group B1 （14/16, 87.50%） and the lipopolysaccharide core type R1 （15/16, 93.75%）. The E. coli isolates exhibited high-level resistance to penicillin, rifampicin and compound sulfamethoxazole, with resistance rates of 100%, 68.75% and 68.75%, respectively, while they were sensitive to polymyxin, tigecycline and meropenem, with resistance rates all being 0. Twelve strains （75.00%） had multi-drug resistant phenotype, 11 strains （68.75%） produced ESBLs, and 15 strains （93.75%） were capable of forming biofilm. A total of 17 antimicrobial resistance genes were detected as positive among the 16 E. coli isolates, and the detection rates for 8 antimicrobial resistance genes such as CTX-M, ant （6′） and sul1 were 100%. Fourteen strains （87.50%） were identified as the CTX-M-1G gene subtype. In addition, a total of 12 virulence genes were detected as positive, among which, 5 virulence genes including iroN, ompA and yijP had 100% detection rate.[Conclusion] A high prevalence of CTX-M gene was observed in the cattle derived E. coli strains in Ta′e reclamation area of Xinjiang Uygur Autonomous Region. Furthermore, these isolates harbored multiple antimicrobial resistance genes and virulence genes, and had high-level antimicrobial resistance, which posed potential threats to the healthy farming of cattle in this region. Therefore,it is necessary to strengthen the monitoring of the CTX-M type E. coli prevalence in this region.

[Objective] This study aimed to characterize the changes in whole transcriptome expression profile of breast muscles during the growth process in Xichuan black-bone chicken before and after hatching. [Method] Breast muscle samples were collected from the Xichuan black-bone chicken embryos incubated for 14 d （marked as X-14 d） and the chicks freshly hatched for 1 d （marked as X-1 d）, respectively. Eukaryotic whole transcriptome sequencing analysis were performed around coding RNA （messenger RNA, mRNA） and non-coding RNA （lncRNA, circRNA and miRNA）. [Result] During the growth process of breast muscles in Xichuan black-bone chicken, the transcriptome levels of a large number of genes had significant changes. Compared with the chicken embryos incubated for 14 d, the chicks freshly hatched for 1 d （X-14 d vs X-1 d） had a total of 3 858 differentially expressed mRNA, including 1 054 upregulated genes and 2 804 downregulated genes. There were 371 differentially expressed lncRNA, including 222 upregulated genes and 149 downregulated genes; there were 316 differentially expressed circRNA, including 148 upregulated genes and 168 downregulated genes; there were 377 differentially expressed miRNA, including 159 upregulated genes and 218 downregulated genes. GO enrichment analysis showed that differentially expressed mRNA was involved in multiple biological processes, such as biological process regulation, stimulus response, localization, positive/negative regulation of biological processes, growth processes, immune system processes, etc. The KEGG pathway enrichment analysis of differentially expressed mRNA demonstrated that multiple signaling pathways were enriched, including adhesion junction, actin cytoskeleton regulation, amino acid biosynthesis, oxidative phosphorylation, carbon metabolism, citric acid cycle （TCA cycle）, tight junction, gap junction, metabolic pathway, focal adhesion, glycolysis/gluconeogenesis, pyruvic acid metabolism, melanogenesis, Notch signaling pathway, etc. The significantly differentially expressed genes were mainly related to multiple biological traits of Xichuan black-bone chickens such as growth trait, meat quality trait, lipid trait, melanogenesis trait, and immune system. [Conclusion] As important components of the transcriptome, mRNA, lncRNA, circRNA, and miRNA played crucial roles in the growth and development of Xichuan black-bone chicken. Our results provided references for analyzing the genetic regulation mechanism in the growth and development process of breast muscles in Xichuan black-bone chicken.

[Objective] This study was conducted to characterize the changes in whey protein profile during the fermentation process of traditional koumiss from Inner Mongolia. [Method] Traditional koumiss was prepared using mare milk collected from Xianghuang Banner, Xilin Gol League, Inner Mongolia, with fermentation temperature at （22±2） ℃, and manual mixing 5 times per day, 300 beats each time. The koumiss samples were taken every 12 h during the 0-96 h fermentation process, and whey protein was collected by centrifugation. Variations in Koumiss whey protein profile during the fermentation process were analyzed by the optimized SDS-PAGE. [Result] The optimized SDS-PAGE conditions were as follows: the concentrations of separation gel and spacer gel were 12% and 5%, respectively; the electrophoresis voltage for separation gel was 180 V, and the electrophoresis time was 300 min; the sample loading amount and concentration were 16 μL and 0.5 μg/μL samples, respectively; the gel was stained with modified Coomassie brilliant blue for 12 h and then decolorized for 12 h. Within 0-12 h of fermentation, the koumiss whey protein contents increased and peaked （5.12 μg/μL） at 12 h, and then fell with the extension of fermentation time, decreasing to 3.92 μg/μL at 96 h of fermentation. SDS-PAGE analysis showed that a total of 13 effective bands of whey protein within the molecular weight range of 10-70 kDa were observed. During the fermentation process, the contents of 3 types of whey protein, β-lactoglobulin, lysozyme C, and α-lactalbumin, fluctuated to varying degrees. The sum of their contents peaked at 72 h of fermentation, accounting for 85.73% of the total whey protein contents and maintained high levels during the fermentation process. It was indicated that they were the main components of whey protein in traditional koumiss within the fermentation process of 96 h. Among them, the content of β-lactoglobulin was the highest, accounting for an average of 38.92% of the total whey protein contents. The content of casein with the molecular weight range of 20-40 kDa began to decrease after 24 h of fermentation, and the corresponding bands disappeared till 60 h. The protein with a molecular weight of 10.33 kDa was depleted within 12 h of fermentation and reappeared at 60 h, and its content gradually increased with the extension of fermentation time and peaked at 84 h, accounting for 9.84% of the total whey protein contents. The protein with a molecular weight of 49.80 kDa began to appear after 72 h of fermentation, and its content reached 4.11% of the total whey protein contents at 96 h. Compared to the other whey protein components, the content of β-lactoglobulin and immunoglobulin had minor changes during the fermentation process. [Conclusion] The whey protein contents with the molecular weight range of 10-70 kDa in traditional koumiss from Inner Mongolia had regular increase and decrease within 96 h of fermentation. The main protein that was digested and decomposed was casein. There were some differences in the composition and content of whey protein in different fermentation stages of koumiss, while the original main components β-lactoglobulin, lysozyme C, and α-lactalbumin maintained higher levels. From the middle stage of fermentation, the proportion of peptides with relatively small molecular weight （10.33 kDa） in the whey protein of koumiss gradually increased. Our results showed that the traditional koumiss not only retained the original nutritional value of whey protein in mare milk, but also added some easily absorbed small molecular weight proteins through fermentation.

[Objective] This study was conducted to assess the effects of partly replacing whole-plant corn silage with quinoa straw micro-silage on production performance, nutrient apparent digestibility, and serum indexes of fattening Simmental crossbred cattle. [Method] A total of 36 Simmental crossbred cattle with good physical condition and initial weight of around 450 kg were selected and randomly assigned into the following 4 groups： a control group and three experiment groups. There were 9 cattle in each group, and each head was a replicate. The control group fed a basal diet （TMR）, and quinoa straw micro-silage was used to replace whole-plant corn silage at ratios of 10%, 30%, and 50% on the basis of roughage in the basal diet in experiment group 1, experiment group 2, and experiment group 3, respectively. The pre-feeding period was 15 d, and the formal feeding period was 60 d. The body weight and feed intake status of the experimental beef cattle in each group during the experiment period was recorded to calculate the average daily gain, average daily feed intake, and average feed to gain ratio. Diet and fecal samples were collected to determine the contents of main nutrients, and to calculate the nutrient apparent digestibility. At the end of the feeding experiment, blood were collected to prepare serum samples, and the serum biochemical indexes, antioxidant capacity indexes, and immune indexes were measured. [Result] Compared with the control group, the experiment group 1 had significantly （P<0.05） increased average daily gain, while had significantly （P<0.05） reduced average feed to gain ratio. The apparent digestibilities of dry matter （DM）, crude protein （CP）, crude fiber （CF）, neutral detergent fiber （NDF）, and acidic detergent fiber （ADF） were significantly lower （P<0.05） in experiment group 1, experiment group 2, and experiment gruop 3 than those in the control group. In experiment group 1, the serum activities of aspartate aminotransferase （AST）, alanine aminotransferase （ALT）, superoxide dismutase （SOD）, and glutathione peroxidase （GSH-Px）, the total antioxidant capacity （T-AOC）, as well as the contents of IgG and IgM were significantly （P<0.05） higher than those in the control group, while the serum level of MDA was significantly （P<0.05） lower than that in the control group. [Conclusion] Partly replacing whole-plant corn silage with quinoa straw micro-silage in the diet of fattening Simmental crossbred cattle increased the daily gain, reduced feed to gain ratio, and enhanced the antioxidant and immune ability. Substitution at a ratio of 10% was recommended.

[Objective] This study aimed to explore the effects of exogenous nitrogen priming on seed germination characteristics of Bothriochloa ischaemum. [Method] The Bothriochloa ischaemum seeds were used as experimental materials. After priming with different concentrations （0, 70, 140, 280, 560, 1 120 mmol/L） of NH₄NO₃ solution for 0 （CK）, 3, 6, 9, and 12 h, respectively, the changes in seed germination rate, germination index, mean germination time, and seedling vigor index were analyzed to reveal the responses of Bothriochloa ischaemum seed germination to exogenous nitrogen priming. [Result] Nitrogen concentration, priming time and their interaction had extremely significant （P<0.01） effects on the seed germination rate, germination index, mean germination time, and seedling vigor index of Bothriochloa ischaemum. The seed germination rate, germination index, and seedling vigor index of Bothriochloa ischaemum showed an upward trend when the concentrations of NH₄NO₃ solution ranged from 0 to 140 mmol/L, and exhibited a downward trend when the concentrations of NH₄NO₃ solution ranged from 280 to 1 120 mmol/L, while the change trend of mean germination time was the opposite. [Conclusion] The seed germination ability of Bothriochloa ischaemum was improved with the lower concentrations （≤140 mmol/L） of NH₄NO₃ solution priming, and was inhibited with the higher concentrations （≥280 mmol/L） of NH₄NO₃ solution priming. The optimal treatment for Bothriochloa ischaemum seeds was priming with NH₄NO₃ solution at concentration of 140 mmol/L for 6 h in production practice.

[Objective] The purpose of this study was to screen the candidate lactic acid bacterial strains for preparing forage silage, so as to improve the fermentation quality of forage silage. [Method] Lactic acid bacterial strains were isolated from the leaves of 8 varieties of gramineous forages, including Pennisetum sinese, Eleusine indica, Imperata cylindrica and so on. On the basis of traditional microbiological identification techniques, molecular biological identification methods and 16S rDNA sequence diversity analysis were used to identify the suspected lactic acid bacterial strains isolated. The performance in growth, acid production and salt tolerance of the lactic acid bacterial strains was characterized. Their growth tolerance under pH value of 3.0, 3.5 and 4.0, as well as NaCl concentrations of 0.02, 0.04, 0.06, 0.08 and 0.10 mg/mL was assessed. Furthermore, their inhibitory effects against Candida, Staphylococcus aureus and Salmonella typhimurium were evaluated. [Result] A total of 30 suspected lactic acid bacterial strains were isolated from the surface of forage leaves. Following phenotypic identification and molecular biological identification, 10 strains of lactic acid bacteria were identified as belonging to the genera of Weissella, Pediococcus and Levilactobacillus, including 3 strains of L. brevis, 2 strains of P. pentosaceus, 2 strains of L. plantarum, 1 strain of W. cibaria, 1 strain of L. pentosus and 1 strain of L. coryniformis. The performance in growth rate and acid production varied among different strains. There were strain-specific salt and acid resistance as well as antibacterial property as well. By comprehensively comparing the biological characteristics of the 10 strains, L. plantarum Lab7 had better performance in salt and acid resistance, while L. brevis Lab1 and L. coryniformis Lab10 had good performance in growth rate, acid production ability, salt and acid resistance, and antibacterial property. [Conclusion] The naturally isolated lactic acid bacterial strains of forage origin, L. plantarum Lab7, L. brevis Lab1 and L. coryniformis Lab10 were screened as candidate strains for lactic acid bacterial preparation used in fermentation of forage silage, and had the potential for further development.

[Objective] The aim of the present study was to explore the responses of antioxidant capacity of different parts of alfalfa to the exogenous selenium priming duration, and to provide references for the production of selenium-rich alfalfa grass products by seed priming technology. [Method] Alfalfa seeds were subjected to priming treatment with 0.5 mmol/L sodium selenite solution for 0, 3, 6, 9, and 12 h, respectively. The activities of superoxide dismutase （SOD）, catalase （CAT）, ascorbate peroxidase （APX） and glutathione reductase （GR） as well as the content of malondialdehyde （MDA） in the whole plant, cotyledon, and radicle of the alfalfa seedlings treated for different priming durations were determined and statistically compared. [Result] With the prolongation of selenium priming duration, the activities of SOD, CAT, APX, and GR of the whole plant, cotyledon, and radicle of the alfalfa seedlings all increased, whereas their content of MDA increased first and then decreased. For the whole plant, cotyledon, and radicle, significantly （P<0.05） lower and significantly （P<0.05） higher activities of both SOD and CAT were observed at 0 h and 12 h priming compared with the other priming durations, respectively. The APX activity of cotyledon was significantly （P<0.05） reduced at both 0 h and 3 h priming, and was significantly （P<0.05） elevated at 12 h priming. The significantly （P<0.05） lowest and the significantly （P<0.05） highest APX activity of both radicle and whole plant were observed at 0 h and 12 h priming, respectively. The whole plant, cotyledon, and radicle had the significantly （P<0.05） lowest GR activity at 0 h priming. Their GR activity all reached to the peak at 12 h priming, with a statistically significant （P<0.05） difference observed in the whole plant. The lowest MDA content of cotyledon was observed at 12 h priming, which exhibited statistically significant （P<0.05） differences compared with that at 0 h and 3 h priming. The MDA content of the whole plant peaked at 3 h priming, declined at 6 h priming, and decreased to the lowest level at 12 h priming, showing statistically significant （P<0.05） differences compared with that at 0 h, 3 h, and 6 h priming. The MDA content of the radicle peaked at 3 h priming, declined at 6 h priming, and decreased to the lowest level at 12 h priming, showing statistically significant （P<0.05） differences compared with the other priming durations. Under the same priming duration, the activities of SOD, CAT, APX, GR and the content of MDA in the radicle were all significantly （P<0.05） higher than those in the cotyledon and whole plant, with radicle being the highest followed by the whole plant and cotyledon. [Conclusion] The effects of selenium priming on the antioxidant capacity depended on the parts of the alfalfa seedlings and priming duration. The antioxidant enzyme activities of the whole plant, cotyledon and radicle of the alfalfa seedlings increased with the prolongation of selenium priming duration, while the change trend of MDA content was the opposite. Selenium priming had limited affects on the cotyledon and had great affects on the radicle. For the alfalfa seedlings, selenium priming concentration at 0.5 mmol/L (sodium selenite solution) and priming for 12 h were the optimal conditions.

[Objective] This study aimed to investigate the effects of the dietary supplementation of yeast cultures on slaughter performance as well as muscular contents of amino acid and functional component in Small-tail Han sheep. [Method] A total of 40 healthy Small-tail Han sheep lambs with similar body weights [（17.5±1.2）kg] at approximately 90 d of age were selected and randomly assigned to a control group （n=20） fed basal diet or a YSD group （n=20） fed basal diet supplemented with 0.1% yeast cultures. The feeding trial lasted for 90 days, preceded by a 10-day adaptation. After the feeding trial, 10 lambs from each group were randomly selected and slaughtered. The slaughter performance indicators, such as live weight before slaughter, carcass weight, carcass fat content （evaluated by GR value）, pH value of the longissimus dorsi, and slaughter percentage rate were measured or calculated. Muscular tissue samples, including longissimus dorsi, latissimus dorsi, biceps femoris, and intercostal muscle, were taken from the slaughtered sheep. A total of 19 amino acids and 3 functional components were quantitatively analyzed by using ultra high performance liquid chromatography coupled with triple quadrupole mass spectrometry （UPLC-QqQ-MS）. [Result] In terms of slaughter performance, there were no significant （P>0.05) differences in live weight before slaughter, carcass weight, and slaughter rate between control group and YSD group; while significantly （P<0.01） reduced GR value and significantly （P<0.05） elevated pH value of the longissimus dorsi were observed in YSD group. Compared with control group, YSD group had higher levels of Thr （P<0.01）, Lys （P<0.01）, Hyp （P<0.01）, Gly （P<0.01）, total essential amino acids （EAA） （P<0.01）, Asn （P<0.05）, Ser （P<0.05）, Gln （P<0.05）, and total non-essential amino acids （NEAA） （P<0.05） in the longissimus dorsi. Increased contents of His （P<0.01）, Gln （P<0.01）, Phe （P<0.05）, Val （P<0.05）, Lys （P<0.05） and decreased contents of Ser （P<0.05） were found in the latissimus dorsi in YSD group. YSD group had higher concentrations of His （P<0.01）, Val （P<0.05）, Cit （P<0.05）, and Tyr （P<0.05） in the biceps femoris. In both latissimus dorsi and biceps femoris, significantly （P<0.05） elevated contents of EAA, NEAA, and total flavor amino acids （FAA） were observed in YSD group. In the intercostal muscle, the contents of Glu, EAA, NEAA, FAA, and total delicious amino acids （DAA） in YSD group were significantly （P<0.05） higher than those in control group, while the differences in the contents of 8 EAA and 10 NEAA between control group and YSD group were not statistically significant （P>0.05）. In addition, dietary supplementation of yeast cultures elevated the L-carnitine content in the longissimus dorsi （P<0.01）, latissimus dorsi （P<0.01）, and intercostal muscle （P<0.05）, as well as the inosinic acid content in the longissimus dorsi （P<0.01）. [Conclusion] Dietary supplementation of 0.1% yeast cultures has good performance in decreasing the carcass fat content and improving the muscular contents of amino acid and functional component in Small-tail Han sheep.

[Objective] This study was conducted to evaluate and compare the meat quality of different sheep breeds in Inner Mongolia. [Method] A total of 60 confined sheep belonging to 5 breeds, including Sonid sheep （selected from Sonid Right Banner, Xilin Gol League, n=12）, Ujimqin sheep （selected from East Ujimqin Banner, Xilin Gol League, n=12）, Chahar sheep （selected from Xianghuang Banner, Xilin Gol League, n=12）, Inner Mongolia fine wool sheep （selected from Zhenglan Banner, Xilin Gol League, n=12）, and Ordos fine wool sheep （selected from Uxin Banner, Ordos City, n=12） were randomly selected. After slaughter, 200 g longissimus dorsi muscle and 200 g biceps femoris samples eliminating fascia and fat were collected from each sheep, respectively. The physical indicators （color, cooked meat rate, shear force and water loss rate）, the contents of traditional nutritional components （water, fat and protein）, and the compositions and contents of amino acids （7 kinds of essential amino acids and 10 kinds of non-essential amino acids） of longissimus dorsi muscle and biceps femoris samples collected from the 5 sheep breeds were assessed and statistically compared. [Result] The longissimus dorsi muscle and biceps femoris of Ordos fine wool sheep and Sonid sheep had better perfomance in color. There were no significant （P>0.05） differences in cooked meat rates of longissimus dorsi muscle among the 5 sheep breeds. Chahar sheep had the highest cooked meat rate of biceps femoris. The water loss rates of longissimus dorsi muscle and biceps femoris of Ujimqin sheep were significantly （P<0.05） lower than those of the other 4 sheep breeds. The shear force of longissimus dorsi muscle and biceps femoris of Sonid sheep was relatively lower among the 5 sheep breeds. In longissimus dorsi muscle and biceps femoris, the highest water content, the lowest fat content and the highest protein content were observed in Chahar sheep, Ujimqin sheep and Sonid sheep, respectively. Ordos fine wool sheep had the highest total amino acid contents in longissimus dorsi muscle and biceps femoris, had higher contents of 7 kinds of essential amino acids in longissimus dorsi muscle, and had significantly （P<0.05） higher contents of 7 kinds of essential amino acids in biceps femoris than those of the other 4 sheep breeds. The ratios of essential amino acid to total amino acid （EAA/TAA） of longissimus dorsi muscle and biceps femoris of the 5 sheep breeds were all around 40%, and those of essential amino acid to non-essential amino acid （EAA/NEAA） were all above 60%, which met the recommended values for high-quality proteins by FAO/WHO. [Conclusion] Although the 5 sheep breeds in Inner Mongolia had differences in the main meat quality indicators, they were all high-quality protein sources due to the high content and balanced composition of EAA. Ordos fine wool sheep performed better in terms of meat TAA and EAA contents, while Ujimqin sheep had the characteristics of high-protein and low-fat meat.

[Objective] The aims of the present study were to assess the biological characteristics of Lactobacillus plantarum derived from Yichun forest pig and to comprehensively evaluate its application potential in the development of probiotic preparations. [Method] A lactic acid bacterial strain （P1M1） isolated from the feces of the healthy forest pig in Yichun City, Heilongjiang Province, was biochemically identified and then molecularly confirmed by using 16S rDNA PCR amplification and sequencing technology. The curves of growth and acid production of the strain were drawn, and its tolerance to acid （pH values at 2.0, 3.0 and 4.0） and bile salt （concentrations at 0.15% and 0.30%） were evaluated. The sensitivity of the strain to 13 antimicrobial agents and its inhibitory effect on Staphylococcus aureus （S. aureus） of porcine origin were examined. Tests were also conducted to assess the free radical scavenging ability, exopolysaccharides yield and safety to mice of the strain. [Result] Based on the biochemical and molecular identification results, P1M1 strain was identified as Lactobacillus plantarum （L. plantarum）. L. Plantarum P1M1 strain had glycolytic ability. Its logarithmic growth phase was 2-10 h of cultivation. After 18 h of cultivation, the pH value of its culture medium stabilized at 3.8-3.9. Its 3 h survival rates at pH values of 2.0, 3.0 and 4.0 were （48.97±0.61）%, （64.19±0.94）% and （78.44 ± 1.36）%, respectively, and those at bile salt concentrations of 0.15% and 0.30% were （53.86±1.14）% and （32.87±0.75）%, respectively. It was sensitive to erythromycin, enrofloxacin, norfloxacin, tobramycin, ampicillin, amoxicillin, cefoperazone, cefradine and ceftazidime, and had pronounced inhibitory effect on S. aureus of porcine origin. The scavenging rates of its cell-free supernatant against DPPH free radical, hydroxyl radical and ABTS free radical were （91.65±1.44）%, （87.32±0.22）% and （89.79±0.59）%, respectively, all significantly （P<0.05） higher than those of its intact cell suspension. Its exopolysaccharides yield was （796.73±2.43） mg/L. No death or organ damage was observed after continuous gavages of the L. plantarum P1M1 strain to mice for 2 weeks. [Conclusion] Forest pig derived L. plantarum P1M1 strain shows an early entrance into the logarithmic growth phase, has glycolytic characteristics, strong acid producing ability, and tolerance to acid and bile salt. It is sensitive to various antimicrobial agents and capable of inhibiting the growth of S. aureus of porcine origin. Furthermore, it has strong antioxidant capacity and high exopolysaccharides yield, and is safe for mice. Accordingly, it can be used as a candidate strain for the development of probiotic preparations.

[Objective] The present study aimed to assess the anesthetic effect of xylazine hydrochloride in rabbits. [Method] Twelve New Zealand rabbits were assigned into the following four groups at random with 3 rabbits in each group: an ear intravenous injection （IV） with fixation group, a buttocks intramuscular injection （IM） with fixation group, an ear IV without fixation group, and a buttocks IM without fixation group. The rabbits in different groups were given xylazine hydrochloride at a dosage of 3 mg/（kg·BW） by corresponding administration approaches. After administration, the rabbits in the fixation groups were in supine position with head and limbs fixed, and those in the non-fixation groups were in natural prone position. Thirty min post the first administration, the rabbits were given xylazine hydrochloride again at a dosage of 2 mg/（kg·BW） by the same approach as the first administration. Basic vital signs and anesthetic reaction indexes of the rabbits were monitored 10 min prior to administration as well as 5, 30 and 60 min post the second administration. [Result] The respiratory and pulse frequencies of the four groups after administration of xylazine hydrochloride decreased significantly or extremely significantly （P<0.05 or P<0.01） compared with those before administration. At 60 min after administration, the pulse frequency of IM fixation group was the lowest, which was significantly （P<0.05） lower than that of IV non-fixation group. The rectal temperature of the four groups at 30 min after administration was significantly （P<0.05） lower than that before administration. Except for the IV non-fixation group, the rectal temperature of each group at 60 min after administration was extremely significantly （P<0.01） lower than that before administration. At 60 min after administration, the rectal temperature of IM fixation group was the lowest, which was extremely significantly （P<0.01） lower than that of IV non-fixation group. In IM fixation group, no righting reflex, eyelash reflex and pain reflex were observed at different time points after administration. In IV non-fixation group, the righting reflex, eyelash reflex and pain reflex were observed in all 3 rabbits at 60 min after administration.The anesthetic period of IM fixation group was the longest, which was significantly （P<0.05）longer than that of IV fixation group and was extremely significantly （P<0.01） longer than that of IV non-fixation group and IM non-fixation group. [Conclusion] Xylazine hydrochloride should be administered by the route of IM in anesthesia of rabbits. A first administration at the dosage of 3 mg/（kg·BW） is recommended, and a subsequent administration at the dosage of 2 mg/（kg·BW） should be given 30 min later. The rabbits should be fixed immediately after administration.

[Objective] To investigate the correlation of body weight, carcass weight, and body measurement of Wuliangshan sooty chicken of different genders. [Method] A total of 60 18-week-old Wuliangshan sooty chickens with half males and half females were chosen, and their body weight, carcass weight, body oblique length, keel length, tibia length, tibia circumference, hip width, chest width, and chest depth were measured. An independent sample t-test was used for statistical comparison. For correlation analysis, Pearson analysis was employed. [Result] The males had extremely significantly （P<0.01） higher body weight, carcass weight, body oblique length, keel length, tibia length, tibia circumference, hip width, chest width, and chest depth than those of the females. Extremely significantly （P<0.01） positive correlations between body weight and carcass weight, keel length, tibial circumference were found in the males. The females′ body weight had extremely significantly （P<0.01） and significantly （P<0.05） positive correlation with carcass weight and tibial circumference, respectively. [Conclusion] The male Wuliangshan sooty chicken had much higher body weight and measurement than the female ones. Body weight was positively correlated to carcass weight and tibial circumference. Selected body measurement associated with bone development, such as keel length, tibial length and tibial circumference, had certain correlation.

[Objective] The aims of the present study were to establish an ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry （UHPLC-MS/MS） method for simultaneous detection of 64 drugs in compound feed, and to improve the detection efficiency of illegal additives. [Method] Waters HSS T3 column （2.1 mm×100 mm, 1.8 μm） was used for separation. Gradient elution was performed using 0.1% formic acid aqueous solution as mobile phase A and acetonitrile containing 0.1% formic acid as mobile phase B, respectively, with a flow rate of 0.40 mL/min and sample size of 2 μL. Positive-ion electrospray ionization （ESI） source scanning mode was used for detection, and multiple reaction monitoring （MRM） mode was used for signal acquisition. The recovery rates of the target drugs obtained with 4 kinds of sample extraction solvents and 2 types of solid-phase extraction column were compared to determine the optimal method of sample pretreatment. Detection of the 64 drugs in 100 batches of compound feed samples of different sources collected in Ningxia Hui Autonomous Region was carried out with the established UHPLC-MS/MS method. [Result] The compound feed samples were extracted with acetonitrile aqueous solution （acetonitrile∶water=8∶2, V/V） containing 0.2% formic acid after homogenization. Oasis PRiME HLB solid-phase extraction column was used to purify the samples. The recovery rates of most target drugs was above 60%. In the concentration range of 5.0-200.0 μg/L, a good linear relationship of the 64 drugs was observed, and their correlation coefficients （R） were all greater than 0.99. The limit of quantitation of different drugs was 5.0-10.0 μg/kg. The average recovery rates of 3 spiking levels at 5.0, 20.0 and 50.0 μg/kg ranged from 41.00% to 120.49%. The intra- and inter-assay relative standard deviations （RSDs） were 0.54%-15.94% and 1.25%-13.64%, respectively. No target drug was detected in the 100 batches of compound feed samples. [Conclusion] The established UHPLC-MS/MS method has good linear relationship, high recovery rate, good precision, high reproducibility and good operability, and can be used for screening the 64 drugs illegally added in compound feed.

[Objective] To determine the process parameters of production technology of a vaginal probiotic preparation using lactic acid bacteria of horse origin. [Method] A Lactobacillus gasseri strain isolated from Mongolian horse vagina, was used as a starter to product the probiotic preparation. Fermentation technology and response surface method were employed to optimize the strain′s fermentation medium and process parameters as well as the probiotic preparation′s formulation and process parameters. [Result] Lactose and soybean peptone had significant impacts on growth performance of the bacterial powder. When the initial pH value of the fermentation broth was set to 6.6, the temperature was set to 40 ℃, and the inoculation amount was set to 6%, the fermentation performance of the bacterial powder was largely influenced. Using pharmaceutical preparation technology and response surface method, the probiotic preparation′s formulation and process parameters were then adjusted. When the mixing ratio of bacterial powder to starch, micro-powder silica gel, and micro-crystalline cellulose was 167.05∶1.61∶1 and the rotating speed of multi-functional medicine machine was 20 r/min at 60 ° angle, the number of live bacteria in the obtained probiotic preparation was higher. [Conclusion] The critical process parameters for production of vaginal probiotic preparation with horse origined Lactobacillus gasseri were determined, providing a foundation for further explorations on the use of probiotic preparations made by live bacteria to prevent and treat horse vaginal infection.

[Objective] The aim of the present study was to assess the effects of different stresses on the agronomic traits, physiological indicators and endogenous hormones of Lotus corniculatus. [Method] Using Lotus corniculatus as the experimental material, 3 stress treatments, including low nutrition （LN）, high bicarbonate （HB） and low phosphorus （LP） were set up by preparing different nutrient solutions. Hoagland′s nutrient solution prepared with distilled water was used as blank control （CK）. Lotus corniculatus seedlings at 2-3 leaves stage were transplanted into bottles containing different nutrient solutions, with 5 seedlings in each bottle and 15 bottles for each treatment. The nutrient solutions were changed every 3 d. Plants were harvested after 1 month of cultivation. The agronomic traits, physiological indicators and endogenous hormone levels of Lotus corniculatus under different stress treatments were measured and statistically compared. Membership function analysis method was used to comprehensively evaluate the effects of different stress treatments on the agronomic traits, physiological indicators and endogenous hormone levels of Lotus corniculatus. The growth performance of Lotus corniculatus under different stresses were analyzed. [Result] The plant height of Lotus corniculatus was the highest under LP treatment. Compared with CK, the root length, rhizosphere diameter, stem thickness, root volume, number of branches, above-ground and under-ground fresh weights, and single plant fresh weight of Lotus corniculatus under the 3 stress treatments all decreased, while the above-ground and under-ground dry matter contents increased. The root to shoot ratios of fresh weight and dry weights were the highest under LN treatment. Under LN treatment, the taproot activity of Lotus corniculatus was the highest, and the fibrous root activity was significantly （P<0.05） higher than that under the other treatments. The leaf chlorophyll content under LP treatment was significantly （P<0.05） higher than that under the other treatments, and the stem chlorophyll content was the highest under HB treatment. Under the 3 stress treatments, leaf protein content of Lotus corniculatus was significantly （P<0.05） lower than CK, stem protein content was higher than CK, leaf malondialdehyde content was significantly （P<0.05） higher than CK, stem malondialdehyde content was significantly （P<0.05） lower than CK, and both leaf and stem proline contents were higher than CK. The 3 stress treatments significantly （P<0.05） reduced the stem superoxide dismutase and peroxidase activities of Lotus corniculatus, and significantly （P<0.05） increased the stem catalase activity and the leaf glutamine synthetase activity. HB and LP stress treatments significantly （P<0.05） reduced the leaf superoxide dismutase and peroxidase activities of Lotus corniculatus. LN and LP stress treatments significantly （P<0.05） reduced the leaf catalase activity and significantly （P<0.05） increased the stem glutamine synthase activity. Compared with CK, the contents of acetylene （ACC）, jasmonic acid and its derivatives （JA） in Lotus corniculatus significantly （P<0.05） decreased under the 3 stress treatments, while the contents of free cytokinin （CTK）, abscisic acid （ABA） and gibberellins （GAs） significantly （P<0.05） increased. Except for the ACC/BHA under LP treatment, the ratios of ACC to the other endogenous hormones in Lotus corniculatus decreased to varying degrees under the 3 stress treatments, with some ratios less than 1. The membership function analysis showed that the comprehensive growth performance of Lotus corniculatus was in the order of LP treatment>CK>HB treatment>LN treatment. [Conclusion] Based on the various indicators, low phosphorus stress had minor impacts on the growth of Lotus corniculatus, while high bicarbonate and low nutrient stresses had a greater impact. Under low phosphorus, high bicarbonate and low nutrient stresses, Lotus corniculatus can regulate its growth and development by adjusting the morphological structure, activating the antioxidant system and balancing endogenous hormones, thereby adapting to the adverse environments.

[Objective] The aim of the present study was to analyze the research trend and hotspot of heavy metal passivation during organic waste composting process. [Method] The literature published from 2000 to 2022 and indexed by the Web of Science （WoS） core collection database on heavy metal passivation during organic waste composting process were used as the data source. CiteSpace 6.2.R6 and VOSviewer 1.6.18 bibliometric visualization software were employed to assess the number of publications and the corresponding countries （regions）, authors, institutions and keywords, and to clarify the research trend and hotspot in this research field. [Result] From 2000 to 2022, a total of 1 266 papers on heavy metal passivation during organic waste composting process were published, with an overall upward trend in annual publication volume. From 2020 to 2022, 345 papers were published, accounting for 27.25% of the total number of publications. Chinese scholars led the research field in terms of publication volume by countries （regions）, with 301 papers published, accounting for 23.78% of the total number of publications. From the perspective of publication volume and collaborative relationships among the authors, KALAMDHAD Ajay S and ZHANG Zengqiang had the highest number of publications, and both published 23 papers, accounting for 1.82% of the total number of publications. The highest number of collaborative authors were observed between the teams of ZHANG Jiachao and ZENG Guanming, indicating an intimate collaborative relationship. From the perspective of institutional publication volume and collaborative relationships, the Spanish National Research Council ranked the first with 96 papers published, accounting for 7.58% of the total number of publications. The Spanish National Research Council and the Chinese Academy of Sciences were the most active institutions in this research field and had the closest collaboration with the other institutions. The top 6 keywords with high occurrence frequency were heavy metals, sewage sludge, municipal solid waste, organic matter, soil and compost, with occurrence frequencies of 724, 441, 210, 187, 158 and 158, respectively. Among the top 10 keywords with high occurrence frequency, sewage sludge, bioavailability, growth, heavy metals, municipal solid waste and soil had intermediary centrality greater than 0.1, and their intermediary centralities were 0.78, 0.52, 0.42, 0.30, 0.25 and 0.18, respectively. A total of 10 categories of keywords were clustered in this research field, including sewage sludge, organic amendments, organic fraction of municipal solid waste, greenhouse gas, C/N ratio, heavy metals, organic waste, and so on. The keyword zinc had the highest burst strength at 16.57 and received attention from 2004 to 2015. Biochar, food waste, microbial community, transformation and organic amendments were the dominant burst keywords from 2017 to 2022. [Conclusion] This study clarified the research trend and hotspot of heavy metal passivation during organic waste composting process. The impacts of different organic wastes on heavy metal passivation, the form transformation and stability of heavy metals in organic waste composting, and the enrichment and transfer of heavy metals in composting products may be the focus of the future research.

[Objective] The aim of the present study was to characterize the succession of fungal community structure of traditional koumiss from Inner Mongolia at different fermentation stages. [Method] Traditional fermentation methods were used to prepare koumiss using the fresh mare′s milk collected from Xianghuang Banner, Xilin Gol League, Inner Mongolia, as the raw material. The traditional koumiss samples were collected at 0, 12, 24, 36, 48 and 96 h of fermentation, and their pH values were measured. Subsequently, high-throughput sequencing technology targeting on the fungal ribosomal DNA internal transcribed spacer （rDNA-ITS） sequence was used to characterize the changes of fungal community structure at different fermentation stages. [Result] The Chao1 index and Shannon-Wiener′s diversity index analysis demonstrated that in the early stage of fermentation （0-12 h）, the fungal community had decreased abundance and minorly changed diversity. The abundance and diversity of the fungal community increased simultaneously during 12-24 h of fermentation, decreased simultaneously during 24-72 h, and elevated simultaneously during 72-96 h. Both reached the initial level of fermentation at 96 h. Within 12 h of fermentation, the pH value of the fermentation system dramatically reduced. It decreased at a slower rate during 12-48 h, and continued to slow down and became gentle during 48-96 h. Two fungal phyla, Ascomycota and Basidiomycota, were identified in the traditional koumiss by high-throughput sequencing targeting on the fungal rDNA-ITS sequence, with the relative abundances of 99.77% and 0.02%, respectively. During the fermentation process, Ascomycota was absolutely dominant. A total of 9 fungal genera were observed, among which Kazachstania and Kluyveromyces were the dominant ones, with the relative abundances of 95.76% and 3.75%, respectively. During 12-96 h of fermentation, the change of relative abundance of Kluyveromyces displayed an alternating trend with that of Kazachstania, and both were present during the whole fermentation process of 96 h. In addition, Kazachstania unispora, Kluyveromyces lactis and Kluyveromyces marxianus were the dominant ones among the 9 fungal species identified, with the relative abundances of 95.76%, 2.10% and 1.63%, respectively. The relative abundances of the 3 dominant species changed in varied manners at the different fermentation stages. [Conclusion] This study clarified the dominant fungal species as well as the succession characteristics of diversity and structure of fungal community during the fermentation process of traditional koumiss from Inner Mongolia. Our results provided a reference for enriching the research on fermentation mechanism, optimizing the fermentation process and improving the fermentation quality of koumiss.

[Objective] This study aimed to screen the suitable mixed sowing combinations of forage grasses for saline-alkali grassland reseeding in Songnen Plain. [Method] The experiment was conducted on the saline-alkali grassland in Qiqihar City, Heilongjiang Province. Hordeum brevisubulatum, a variety of saline-alkali tolerant forage grass widely distributed in Songnen Plain, was used as the dominant forage grass for reseeding. The mixed sowing treatments were set with 4 indigenous varieties of saline-alkali tolerant forage grasses in Songnen Plain, including Puccinellia tenuiflora, Elymus dahuricus, Leymus chinensis and Calamagrostis epigejos. A single sowing treatment with Hordeum brevisubulatum was set as well. In the 4 mixed sowing treatments, the sowing amount of Hordeum brevisubulatum was 30 kg/hm², and that of the other forage grasses was all 15 kg/hm². In the single sowing treatment of Hordeum brevisubulatum, the sowing amount of Hordeum brevisubulatum was 45 kg/hm². Each of the above treatment had 3 reduplicates with 1 plot for each reduplicate. A plot without reseeding （CK） was included. Accordingly, a total of 16 plots were included in this study, and each plot covered an area of around 0.4 hm². Under the condition of minimizing disturbance to the native vegetation, no-tillage reseeding was performed on the experimental plots in 2021. Starting from the second year of reseeding, the soil physical and chemical properties such as bulk density, pH value, salt content （conductivity）, organic matter content, alkali-hydrolyzable nitrogen content, available phosphorus content and available potassium content, as well as the important value of vegetation community of the experimental plots were determined for two consecutive years. [Result] In the second year （2022） of reseeding, compared with CK, the soil bulk density, pH value and conductivity of the mixed sowing treatments and the single sowing treatment decreased to varying degrees, while the soil contents of organic matter, alkali-hydrolyzable nitrogen, available phosphorus and available potassium increased to varying degrees. Compared with the second year of reseeding, the mixed sowing treatments and the single sowing treatment had decreased soil bulk density, pH value and conductivity as well as elevated soil contents of organic matter, alkali-hydrolyzable nitrogen, available phosphorus and available potassium in the third year （2023） of reseeding. The effectively improved soil physical and chemical properties were observed in the mixed sowing treatments and the single sowing treatment in the third year of reseeding. Specifically, the soil bulk density, pH value and conductivity were significantly （P<0.05） lower than those of CK, the soil contents of alkali-hydrolyzable nitrogen, available phosphorus and available potassium were significantly （P<0.05） higher than those of CK, and the soil organic matter content was significantly （P<0.05） higher than CK except for the mixed sowing treatment of Hordeum brevisubulatum+Leymus chinensis. In addition, the lowest soil bulk density, pH value and conductivity were observed in the mixed sowing treatment of Hordeum brevisubulatum+Leymus chinensis, while the highest soil contents of organic matter, alkali-hydrolyzable nitrogen, available phosphorus and available potassium were found in the mixed sowing treatment of Hordeum brevisubulatum+Elymus dahuricus. Compared with CK, there were minor differences in the important values of Poaceae plants and other forbs among the varied mixed sowing treatments and the single sowing treatment in the second year of reseeding, with the highest observed in the mixed sowing treatment of Hordeum brevisubulatum+Elymus dahuricus at 0.60. Compared with the second year of reseeding, the important values of Poaceae plants in various mixed sowing treatments and the single sowing treatment elevated in the third year of reseeding, and they were all higher than those in CK. Furthermore, the highest important value was also observed in the mixed sowing treatment of Hordeum brevisubulatum+Elymus dahuricus at 0.71. [Conclusion] The mixed sowing of Hordeum brevisubulatum+Leymus chinensis had the best performance in ameliorating the soil bulk density, pH value and salt content, and was a preferable mixed sowing combination for improving the severely saline-alkali grasslands. The mixed sowing of Hordeum brevisubulatum+Elymus dahuricus exhibited the best effects on ameliorating the soil contents of organic matter, alkali-hydrolyzable nitrogen, available phosphorus and available potassium as well as vegetation community, and was a superior mixed sowing combination for improving the mild and moderate saline-alkali grasslands as well as the degraded grasslands.

[Objective] To assess the effects of different levels of dried apple pomace （DAP） replacing part of the energy feed in concentrate supplements on in vitro rumen gas production, fermentation parameters, nutrients digestibility and growth performance of fattening Simmental cattle. [Method] Corns in concentrate supplements were partially replaced by DAP at proportions of 0, 4%, 8%, 12% and 16%, respectively. The rumen gas production of each group during 0 to 72 h of fermentation was monitored by using in vitro gas production method, and the fermentation parameters of the artificial rumen fluid were determined at the end of the in vitro gas production test. The nutrients digestibility of the artificial rumen fluid was measured at 48 h of in vitro fermentation. The weight gain indicators of the fattening cattle fed with diets in which corns were partially replaced by DAP at proportions of 4%, 8%, 12% and 16%, respectively, were assessed. [Result] The 4% DAP replacing group had significantly （P<0.05） higher total gas production in comparison to 8% and 16% DAP replacing groups. The gas production of each group was mainly observed in 4 to 24 h of fermentation and tended to be stable during 36 to 72 h of fermentation. After gas production, the pH value of the artificial rumen fluid of each group was in the normal range. The concentration of ammonia nitrogen （NH₃-N） of 8% DAP replacing group was significantly （P<0.05） higher than that of 12% and 16% DAP replacing groups. The concentrations of acetic acid, isobutyric acid, butyric acid, isovaleric acid, and valeric acid of 4% and 8% DAP replacing groups were significantly （P<0.05） higher than those of the remaining groups. The control group had significantly （P<0.05） higher digestibility of dry matter （DM）, crude protein （CP） and neutral detergent fiber （NDF） compared with the remaining groups, and 8% DAP replacing group had significantly （P<0.05） higher digestibility of acid detergent fiber （ADF） compared with the remaining groups. There were no significant （P>0.05） differences in total weight gain and daily weight gain during the test period among the fattening cattle in different groups. [Conclusion] Replacement of partial corns in concentrate supplements with 4% DAP increased the rumen gas production in in vitro fermentation of fattening Simmental cattle. 4% and 8% DAP replacements increased the concentrations of NH₃-N and volatile fatty acid （VFA） in rumen fluid, which was beneficial to rumen fermentation and diet digestion.

[Objective] The dietary nutrients apparent digestibility and daily gain of beef cattle at different growth stages were compared to provide references for ration formulation of beef cattle feeding. [Method] Two groups of Simmental crossbred cattle were randomly selected according to their age and weight. The light weight group comprised of ten 12- to 15-month-old cattle with weights of 250-300 kg. The heavy weight group comprised of ten 15- to 18-month-old cattle with weights of 350-500 kg. The diet was adjusted according to the weight change of beef cattle. The formal test period was divided into early and late test stages. Using ash insoluble in hydrochloric acid （AIA） as endogenous indicator, the apparent digestibility of dietary nutrients was determined by spot fecal collection method. [Result] The overall gain and average daily gain of the light weight group were significantly （P<0.05） different from those of the heavy weight group over the course of the experiment. In the early stage of the experiment, the apparent digestible amount of organic matter （OM）, crude protein （CP）, neutral detergent fiber （NDF）, acid detergent fiber （ADF）, starch, and energy in the diet of light weight group significantly （P<0.05） differed from that of heavy weight group. However there was no significant （P>0.05） difference in the apparent digestibility of OM, CP, NDF, ADF, starch, and energy between the two groups. [Conclusion] Under the conditions of the experimental diet composition, there was no significant difference in the apparent digestibility of dietary nutrients between the beef cattle at the two feeding stages, and the increasing digestible nutrient intake could increase the daily gain.

[Objective] To investigate and analyze the parasitic infection status of thoroughbred horses of different genders and ages in varied months in Zhaosu County of Xinjiang, so as to provide guidelines for the healthy breeding and scientific deworming of the thoroughbred horses in this region. [Method] A total of 122 thoroughbred horses of different ages were randomly selected and divided into 5 groups according to genders and ages, including 30 lactating foals, 25 young mares, 20 young males, 35 breeding mares and 12 stallions. Experiments were carried out according to the modes of group confinement feeding and single stall feeding in the stable to ensure the adequate intake of diet and drinking water for the thoroughbred horses of different ages. The fecal samples were collected in May and October. By using the egg count method, the parasites in the fecal samples were detected, and the parasite infection rate and intensity of the thoroughbred horses of different ages in varied months were estimated. [Result] In May, the infection rates of Oxyuris equi and Eimeria spp in the thoroughbred horses were high, and the infection rates were all higher than 94.00% with the exception of the stallions. Among them, the infection rates of Oxyuris equi and Eimeria spp in the lactating foals were as high as 98.89% and 98.33%, respectively. The infection rates of Parascaris equorum and Eimeria spp in the thoroughbred horses were higher than 93.00% in October, with Parascaris equorum infection rates in the breeding mares reaching 99.52% and Eimeria spp infection rates in the lactating foals reaching 98.33%. In May, the lactating foals had significantly （P<0.05） higher infection intensities of Parascaris equorum, Trichostrongylus spp, Cyathostomum spp and Triodontophorus tenuicollis than the other groups, and had significantly （P<0.05） higher infection intensities of Oxyuris equi, Eimeria spp and Gastrodiscus aegyptiacus than the stallions, but no significant （P>0.05） differences with the other groups. In October, the lactating foals had significantly （P<0.05） higher infection intensities of Parascaris equorum, Trichostrongylus spp and Anoplocephala spp than the other groups except for the breeding mares, had significantly （P<0.05） higher infection intensity of Triodontophorus tenuicollis than the other groups, and had significantly （P<0.05） higher infection intensities of Eimeria spp and Gastrodiscus aegyptiacus than the stallions. The infection intensities of Parascaris equorum and Triodontophorus tenuicollis in the stallions was significantly （P<0.05） lower than the other groups. There were no significant （P>0.05） differences in the infection intensity of Oxyuris equi across the different groups. [Conclusion] The main intestinal parasites found in the thoroughbred horses in Zhaosu County were Oxyuris equi, Eimeria spp, Trichostrongylus spp, Triodontophorus tenuicollis, Cyathostomum spp, Parascaris equorum, Anoplocephala spp, and Gastrodiscus acgyptiacus. The single infections and severe co-infections of the above parasites occurred in the thoroughbred horses of different ages and in varied months. The lactating foals had higher parasitic infection rates and intensities than the thoroughbred horses of the other ages.

[Objective] To evaluate the meat performance, slaughter performance, and meat quality of Dumeng mutton sheep. [Method] A total of 60 Dumeng mutton sheep, half male and half female, were chosen. The live meat performance of the experimental sheep was assessed with ultrasonic backfat tester at the age of 5 months, and they were slaughtered at the age of 6 months to evaluate the parameters associated with slaughter performance, meat quality and edible safety. Furthermore, the differences in indicators of live meat performance, slaughter performance, meat quality and edible safety between ewes and rams were statistically analyzed and compared. [Result] In terms of live meat performance, the rams had significantly （P<0.05） higher psoas muscle thickness and eye muscle area than the ewes, while no significant （P>0.05） difference in backfat thickness between rams and ewes was observed. The backfat thickness and eye muscle area of the rams measured after slaughter were significantly （P<0.05） higher than those of the ewes. The carcass weight, net meat weight, and live weight before slaughter of the rams were significantly （P<0.05） higher in comparison to those of the ewes. While the rams had higher slaughter rate and carcass net meat rate than the ewes, no statistical differences （P>0.05） were found. The thigh bone weight, calf bone weight, thigh bone length, and calf bone length of the ewes were significantly （P<0.05） lower compared with those of the rams. For both rams and ewes, there were positive correlations between the four bone indexes when pairwisely compared, and the thigh bone weight and calf bone weight were more prone to be linearly correlated. The rams had significantly （P<0.05） lower intramuscular fat content than the ewes, and there was no significant （P>0.05）difference in moisture content of carcass muscle between rams and ewes. The muscular contents of lead, chromium, mercury and arsenic of the rams and the ewes were all in line with the edible safety requirements listed in China′ s national standard of Safety Qualification for Agricultural Product （GB 18406.3-2001）. The ewes had significantly （P<0.05） lower muscular contents of chromium and mercury than the rams. [Conclusion] The live meat performance and slaughter performance of Dumeng mutton rams are superior to those of the ewes, while ewes have better meat quality.

[Objective] This study was conducted to assess the effects of adding lactic acid bacteria and sugars on fermentation weight loss, fermentation quality and microbial community structure of wheat straw yellow storage at different compaction densities. [Method] Wheat straw was crushed into proper length and the initial moisture content was adjusted to 60%. After well mixing, it was randomly divide into two equal parts. One part was supplemented with the additives composed of a commercially available microbial agent containing 1×10⁵ CFU/g of Lactobacillus plantarum （5 g/t） and white sugar （10 kg/t）, evenly sprayed with 3% sterile water, and then compacted to prepare yellow storage at the densities of 450, 500 and 550 kg/m³ （additive treatment group）, respectively. The other part was evenly sprayed with 3% sterile water, and then compacted to prepare yellow storage at the densities of 450, 500 and 550 kg/m³ （control group）, respectively. Fermentation weight loss of the yellow storage of the two groups with different compaction densities were measured after fermentation for 1, 3, 6, 15, 35 and 200 d, respectively. At 200 d of fermentation, the yellow storage samples were taken to assess the fermentation quality, microbial quantity and microbial diversity. [Result] From 3 d to 200 d of fermentation, the fermentation weight loss of both groups increased significantly （P<0.05）. At 35 d and 200 d of fermentation, the fermentation weight loss of the additive treatment group was significantly （P<0.05） lower than that of the control group. Compared with the control group, the additive treatment group had significantly （P<0.05） lower pH value, significantly （P<0.05） higher lactic acid content, significantly （P<0.05） reduced ammoniacal nitrogen content, and significantly （P<0.05） elevated acid-base buffering capacity. The number of lactic acid bacteria and yeasts of the additive treatment group was significantly （P<0.05） lower than that of the control group. Lactiplantibacillus and Lentilactobacillus were found as the dominant bacterial genera in both groups, with relative abundance of 22.12%-49.18% and 1.45%-49.91%, respectively, and their total relative abundance exceeded 34.25%. At the compaction density of 450 kg/m³, the relative abundance of Leuconostoc and Enterobacter of the additive treatment group was significantly （P<0.05） lower than that of the control group. At the compaction density of 500 kg/m³, significantly （P<0.05） lower relative abundance of Lentilactobacillus and Leuconostoc as well as significantly （P<0.05） higher relative abundance of Enterobacter, Pantoea, Ralstonia and Weissella were observed in the additive treatment group compared with the control group. At the compaction density of 550 kg/m³, the additive treatment group had significantly （P<0.05） decreased relative abundance of Lentilactobacillus, Enterobacter and Leuconostoc as well as significantly （P<0.05） increased relative abundance of Bacillus and Paenibacillus than the control group. The relative abundance of Lentilactobacillus was negatively correlated with lactic acid content, the ratio of lactic acid to acetic acid, and acid-base buffering capacity （P>0.05）, positively correlated with acetic acid content （P>0.05）, significantly （P<0.05） positively correlated with pH value, and significantly （P<0.01） positively correlated with ammoniacal nitrogen content. The relative abundance of Enterococcus and Lactococcus was significantly （P<0.05） negatively correlated with lactic acid content, significantly （P<0.01） negatively correlated with the ratio of lactic acid to acetic acid as well as acid-base buffering capacity, and significantly （P<0.01） positively correlated with pH value. The number of lactic acid bacteria and yeasts was significantly （P<0.01） positively correlated with pH value and ammoniacal nitrogen content, and significantly （P<0.01） negatively correlated with the ratio of lactic acid to acetic acid. [Conclusion] Increasing compaction density and utilizing microbial additive can reduce the fermentation weight loss and ameliorate the fermentation quality of wheat straw yellow storage.

[Objective] The aims of the present study were to isolate and identify lactic acid bacteria from camel milk in Hutubi County of Xinjiang Uygur Autonomous Region, and to evaluate their inhibitory effects on Staphylococcus aureus （S. aureus）. [Method] A total of 45 healthy camel milk samples were collected from a camel farm in Hutubi County. Lactic acid bacteria were isolated using MRS medium, and molecular biological identification was carried out using PCR amplification and sequencing targeting 16S rDNA sequence. Point inoculate method, agar spot method and Oxford cup double-layer agar diffusion method were used to screen the lactic acid bacteria with inhibitory effects on S. aureus ATCC 29213. The acid tolerance of the lactic acid bacteria was measured by adjusting pH value of MRS medium to 1-10. The bile salt tolerance of the lactic acid bacteria was assessed by adding 0-0.30% ox bile salt to MRS medium. The minimum inhibitory concentration （MIC） and subinhibitory concentration （SIC） of cell-free culture supernatant （CFCS） of the lactic acid bacteria against S. aureus ATCC 29213 were determined using micro-broth dilution method. Changes in inhibitory effect of CFCS on S. aureus ATCC 29213 under different pH value conditions and after enzymatic treatments were examined to preliminarily analyze the antibacterial active substances of CFCS. The inhibitory effect of CFCS on wild strains of S. aureus isolated from camel milk and dairy cow with mastitis were evaluated by Oxford cup double-layer agar diffusion method. [Result] A total of 20 lactic acid bacterial strains belonging to 5 species were isolated from the 45 camel milk samples, including Enterococcus faecalis （n=13）, Lacticaseibcillus rhamnsus （n=1）, Limosilactobacillus fermentum （n=3）, Lactobacillus paracasei （n=1） and Weissella confusa （n=2）. After screening with the above mentioned three methods, a strain of Lacticaseibcillus rhamnsus （L. rhamnsus, designated as KC4） exhibiting the strongest antibacterial effect on S. aureus ATCC 29213 was obtained. KC4 strain had good acid and bile salt tolerance, and showed normal growth in MRS medium with pH values adjusting to 4-7 and addition of ox bile salt at concentrations of 0-0.20%. The MIC and SIC of KC4 strain CFCS against S. aureus ATCC 29213 were 62.5 mg/mL and 7.812 5 mg/mL, respectively. Its antibacterial activity was still effective at pH values of 2-5, but reduced extremely significantly （P<0.01） after enzymatic treatments with pepsin, peroxidase, trypsin, peptidase, protease K, catalase and papain. It had good antibacterial effect on wild strains of camel and dairy cow derived S. aureus. [Conclusion] One strain of L. rhamnsus was obtained from the camel milk in Hutubi County, which had strong inhibitory effect on standard strain of S. aureus and wild strains of S. aureus isolated from camel milk and dairy cow with mastitis. It also exhibited high level tolerance to acid and bile salt, and the possible antibacterial active substances included acids, peroxides and proteins. The results obtained in this study provided potential bacterial resources for the development and utilization of lactic acid bacteria derived from camel milk.

[Objective] To assess the effects of different wilting time and ensiling time on fermentation quality of whole plant corn silage. [Method] The silage corn Zea mays L. var. Quchen 9 was used as raw material of ensiling experiment. At late milky ripeness stage, the whole plant silage corn was harvested and crushed, and was subsequently wilted in the shade for 0 （CK）, 1, 2, 3 and 4 days respectively before being ensiled in separate plastic barrel with volume of 5 L. The fermentation quality was evaluated after 60, 90 and 120 days of ensiling. [Result] The moisture content of corn silage decreased with the extension of wiling time, and the corn silage prepared with raw material wilted for 2, 3 and 4 days had significantly （P<0.05） lower moisture content than CK. The pH value of corn silage prepared with raw material wilted for 2, 3 and 4 days was significantly （P<0.05） higher than that of CK, with the exception of wilted for 2 days and ensiled for 120 days. Wilting time exhibited significant （P<0.05) effects on the contents of lactic acid, butyric acid, neutral detergent fiber （NDF） and acid detergent fiber （ADF）, whereas ensiling time only significantly （P<0.05） affected the contents of lactic acid and butyric acid. In addition, lactic acid content increased with the prolongation of ensiling time, and butyric acid content increased after the raw material being wilted. In CK, corn silage ensiled for 90 and 120 days had significantly （P<0.05） higher NDF concentrations in comparision to that ensiled for 60 days. The fermentation quality of corn silage was diminished as a result of wilting in V-Score analysis using ammoniacal nitrogen, acetic acid, propionic acid, and butyric acid as evaluative indicators. The corn silage prepared with crushed raw material without being wilted （CK） had better fermentation quality. [Conclusion] Corn silage has better performance in comprehensive fermentation quality when the raw material is ensiled for 60 days without wilting. It is not recommended to reduce the moisture content by wilting after crushing and then ensiles when the moisture content of raw material is 74%.

[Objective] The aims of the present study were to assess the optimal ratio of corn straw and spent Flammulina velutipes substrate as roughage in preparation of fermented total mixed ration （FTMR） for beef cattle, and to provide technical support for the high-value utilization of by-products such as mushroom bran. [Method] For the preparation of roughage, a total of 7 treatment groups with different mixing ratios of corn straw and spent Flammulina velutipes substrate were set up. Total mixed ration （TMR） were made from even mixing of corn straw and spent Flammulina velutipes substrate at the ratios of 8∶2 （T1 group）, 7∶3 （T2 group）, 6∶4 （T3 group）, 5∶5 （T4 group）, 4∶6 （T5 group）, 3∶7 （T6 group） and 2∶8 （T7 group） with addition of beef cattle concentrate supplement at a concentrate-roughage ratio of 4∶6 （fresh weight）. TMR samples from different treatment groups were placed into silage bags, and then compacted, sealed, vacuumized and stored in a dark room to naturally ferment for 60 days to prepare FTMR. The nutritional component and mycotoxin content of the prepared TMR and FTMR samples were measured and statistically compared. Furthermore, the fermentation parameters of FTMR were assessed to determine the optimal ratio of corn straw and spent Flammulina velutipes substrate. [Result]①As the ratios of corn straw to spent Flammulina velutipes substrate decreased, the DM content of TMR gradually reduced, the CP content gradually increased, the NDF and ADF contents generally elevated, and the EE content fluctuated. ②As the ratios of corn straw to spent Flammulina velutipes substrate decreased, the DM content of FTMR gradually reduced as well. Compared with the corresponding TMR, the FTMR in T4 group had the lowest DM loss rate. The CP content of FTMR in T3 and T4 groups were significantly （P<0.05） higher than that in the other groups. Compared with the corresponding TMR, the CP content of FTMR in T3 and T4 groups increased. No significant （P>0.05） differences in EE content of FTMR among different groups were observed. Compared with the corresponding TMR, the EE content of FTMR decreased in T1-T4 groups, but increased in T5-T7 groups. The NDF content of FTMR in T1-T5 groups were significantly （P<0.05） lower than that in T6 and T7 groups, with the lowest NDF content observed in T3 group. Compared with the corresponding TMR, the NDF content of FTMR in T3 and T5 groups decreased. The ADF content of FTMR in T1-T5 groups were significantly （P<0.05） lower than that in T6 and T7 groups. Compared with the corresponding TMR, the ADF content of FTMR in T4 and T5 groups decreased. ③The FTMR samples from all the treatment groups had acidic aroma and good fermentation quality. The pH value of FTMR in T3 group was the lowest, which was significantly （P<0.05） lower than that in the other groups. The pH value of FTMR in T4 group was lower as well. As the ratios of corn straw to spent Flammulina velutipes substrate decreased, the LA content of FTMR showed a trend of first increasing and then decreasing, with T4 group having the highest content, followed by T3 group, both of which were significantly （P<0.05） higher than the other groups. As the ratios of corn straw to spent Flammulina velutipes substrate decreased, the AA content of FTMR exhibited a trend of first increasing and then decreasing, with T5 group having the highest content, followed by T4 and T3 groups. Trace level of PA were detected in FTMR samples from all the treatment groups, and there were no significant differences （P>0.05） among the different groups. Trace level of BA were detected in FTMR in T6 and T7 groups, while the other groups were not detected. The AN/TN ratio of FTMR in T3 group was the lowest. FTMR in T6 and T7 groups had the AN/TN ratio exceeding 10%, while the other groups was less than 10%. The differences in AFB₁, ZEN and OTA contents of TMR and FTMR samples among different groups were not significant （P>0.05）. According to the Feed Hygiene Standard （GB 13078-2017）, the mycotoxin content of the TMR and FTMR samples did not exceed the threshold. ④The main effects analysis showed that the fermentation treatment significantly （P<0.05） reduced the ABF₁ and ZEN contents of TMR, while the treatment of the mixing ratios of corn straw and spent Flammulina velutipes substrate, as well as the combination effect of fermentation and mixing ratios, had no significant （P>0.05） effects on the ABF₁ and ZEN contents of the TMR and FTMR samples. In addition, the fermentation treatment, the treatment of the mixing ratios of corn straw and spent Flammulina velutipes substrate, and the combination effect of fermentation and mixing ratios had no significant （P>0.05） effects on the OTA content of the TMR and FTMR samples. [Conclusion] Based on the comprehensive analysis on nutritional component, mycotoxin content and fermentation quality, the preparation of FTMR with corn straw and spent Flammulina velutipes substrate as roughage was an efficient way to preserve and utilize the by-products such as straw and mushroom bran. Corn straw and spent Flammulina velutipes substrate mixed at the ratios of 6∶4 （T3 group） or 5∶5 （T4 group） had the better performance.

[Objective] To determine the causes of morbidity and mortality of some introduced goat kids in a large-scale dairy goat farm in Inner Mongolia, so as to provide a scientific basis for this farm to strengthen the prevention and control of major epidemic diseases. [Method] The pathological anatomy obaservation of the diseased goat kids with typical clinical signs was made. Pathological sections were prepared using aseptically collected lung samples with lesions. Serum was prepared using aseptically collected blood samples, and the goatpox virus antibody in serum was detected by high-sensitive fluorescence technology. The lung tissues as well as nasal and eye swabs were aseptically gathered, and the P32 gene of goatpox virus was detected by PCR assay and sequenced. The obtained the sequences were subjected to comparision with BLAST and homology analysis. [Result] Pathological autopsy showed that there was round pox in oral, nasal, laryngeal, and tracheal mucosa of the diseased goat kids; the lungs were obviously edematous with red pox on the surface, and were opaque and gray-white jelly like following incision; pox was also visible in the rumen, reticulum, omasum, and abomasum mucosa. Histopathologic examination revealed that the alveoli were intensely stained with red; the alveolar interstitium was widened, and the alveolar cavity contained exfoliated epithelial cells; type Ⅱ alveolar epithelial cells proliferated and had a metaplasia into acinar-like shape; there were massive inflammatory cells in the lumen of bronchi. The goatpox virus antibody in serum of the diseased goat kids was tested positive using high-sensitive fluorescence technology. Lung tissue （GTPV-YP1）, nasal swab （GTPV-YP2） and eye swab （GTPV-YP3） samples were collected, and the P32 gene of a predicted length of 983 bp was all amplified by PCR assay from these samples. The P32 gene sequences of GTPV-YP1 and GTPV-YP2 samples had 100% homology with goatpox virus Chinese isolate KC951854.1 and Oman isolate MN072621.1, and the P32 gene sequence of GTPV-YP3 sample was 99.0% homologous to goatpox virus Chinese isolates EF514892.1, HM572329.1, JN596275.1 and MG817382.1. [Conclusion] The goatpox virus infection was determined as the cause of the illness in the introduced dairy goat kids on the farm by pathological anatomy observation, histological examination, serological detection, and pathogen PCR identification.