[Objective] This study was conducted to characterize the change of functional gene expression of active microorganisms in different fermentation stages of koumiss. [Method] The koumiss samples were collected at the early （12 h）, middle （48 h） and late （96 h） stages of fermentation, and the metatranscriptomic libraries were prepared for high-throughput RNA sequencing. After assembly and functional annotation of the sequencing data, the differentially expressed genes （DEGs） were identified to determine the static enrichment of significant DEGs in GO and KEGG signaling pathways. [Result] The koumiss samples of the early, middle and late stages of fermentation generated 12.17 GB clean reads by metatranscriptomic high-throughput sequencing. Sequence assembly and data analysis demonstrated that the expression of genes involved in metabolic process played a dominant role in the fermentation process of koumiss. The identification and assessment of DEGs exhibited that the number of the down-regulated genes was more than that of the up-regulated genes in pairwise comparison of the koumiss samples collected at the three fermentation stages. GO functional enrichment analysis showed that the GO terms highly enriched by DEGs between the samples of early and middle fermentation stages associated with cellular process, metabolic process, organic ring compound binding, and heterocyclic compound binding. The GO terms highly enriched by DEGs between the samples of middle and late fermentation stages included cellular process and cellular macromolecule metabolic process. The GO terms highly enriched by DEGs between the samples of early and late fermentation stages mainly involved cellular process, organic substance metabolic process, nucleoside binding, ribonucleoside binding, and purine nucleotide binding. KEGG pathway enrichment analysis displayed that there was only one signaling pathway （ribosome） in which DEGs between the samples of early and middle fermentation stages significantly enriched. DEGs between the samples of middle and late fermentation stages significantly enriched in the signaling pathways of ether lipid metabolism, aminobenzoate degradation, mRNA surveillance pathway, and steroid biosynthesis. The signaling pathways of steroid biosynthesis, aminobenzoate degradation, mRNA surveillance pathway, ribosome and ethylbenzene degradation were significantly enriched by DEGs between the samples of early and late fermentation stages. [Conclusion] The differential expression of functional genes of active microorganisms was involved in the fermentation process and dynamically changed in different fermentation stages of koumiss. The results obtained in this study provide references for in-depth understanding the fermentation mechanism and optimizing the fermentation process of koumiss.

[Objective] This study was conducted to optimize the glycosylation reaction conditions for flaxseed gum （FSG） and zein, and to characterize the structural and functional properties of the glycosylation product. [Method] Using grafting degree as the evaluation index, the main factors affecting the glycosylation reaction between FSG and zein were optimized by orthogonal test on the basis of one-way test. The structure of the FSG-zein glycosylation product was analyzed by the techniques of scanning electron microscope, Fourier infrared spectroscopy and endogenous fluorescence spectroscopy. Furthermore, the FSG-zein glycosylation product was functionally evaluated in terms of anti-oxidant capacity as well as emulsifying and foaming properties. [Result] The optimized glycosylation reaction conditions for FSG and zein were as follows: the ratio of zein solution to FSG solution was 1︰3, the pH value of the reaction system was 2, the reaction temperature was 90 ℃, and the reaction duration was 90 min. Under these conditions, the grafting degree of the FSG-zein glycosylation product was 77.81%. Scanning electron microscope, Fourier infrared spectroscopy and endogenous fluorescence spectroscopy analyses demonstrated that the initial structures of FSG and zein were significantly changed after the glycosylation reaction, confirming that FSG and zein generated FSG-zein glycosylation compound by glycosylation reaction. At a concentration of 1 mg/mL, the FSG-zein glycosylation product possessed a significantly （P<0.05） higher scavenging rate of ·OH than FSG, and exhibited significantly （P<0.05） elevated scavenging rate of DPPH and ABTS⁺ radical as well as total reducing power than FSG and zein. Significantly （P<0.05） increased emulsifying activity index and stability index as well as significantly （P<0.05） improved foaming ability and stability were observed in the FSG-zein glycosylation product in comparison to FSG and zein. [Conclusion] The glycosylation reaction conditions for FSG and zein were optimized, and the obtained glycosylation product possessed good anti-oxidant capacity as well as emulsifying and foaming abilities.

[Objective] The aim of the present study was to assess the effects of exogenous ascorbic acid （AsA） priming on seed vigor of forage triticale （× Triticosecale Wittmack）under NaCl stress. [Method] Forage triticale 'Jisi No.3' seeds were primed in AsA solutions at the concentrations of 0.5, 1.0, 1.5 and 2.0 mmol/L for 0 （CK）, 4, 8, 16 and 24 h, respectively, and were then germinated under NaCl stress at a concentration of 100 mmol/L. The germination percentage （Gp）, germination index （Gi）, mean germination time （MGT） and seedlings vigor index （SVI） of the seeds were determined and statistically compared. [Result] The priming concentration or duration of the exogenous AsA had extremely significant （P<0.01） effects on Gp, Gi, MGT and SVI of the forage triticale seeds. In addition, the mutual combination effect of both reached significant （P<0.05） level on SVI and extremely significant （P<0.01） level on Gp,Gi and MGT. The highest values of Gp, Gi and SVI as well as the lowest value of MGT were observed in the seeds with AsA priming for 4 h at a concentration of 1.0 mmol/L. In the AsA priming concentration range of 0.5-2.0 mmol/L, the seeds had lower Gp, Gi and SVI as well as higher MGT when they were primed for 24 h in comparison to those at the other priming times. [Conclusion] The effects of AsA priming on seed vigor of forage triticale under NaCl stress were closely related to the priming concentration and duration as well as their synergistic action. Priming with AsA at a concentration of 1.0 mmol/L for 4 h exhibited the most effective improvement in seed vigor of forage triticale under a salt stress environment of 100 mmol/L NaCl.

[Objective] This study was conducted to assess the mechanisms underlying the protective role of honeysuckle extract against Newcastle disease virus （NDV） infection in pigeon. [Method] A total of 40 healthy 28-day-old American king pigeons without NDV vaccination were selected and subjected to a 7-day adaptive rearing. At the age of 35 days, the experimental pigeons were randomly assigned into a honeysuckle extract protective （KO） group （n=10） or a virus challenge control （OE） group （n=10）. The pigeons in KO group drank the water containing 1.2% honeysuckle extract for 7 consecutive days, and at the age of 42 days, they were intramuscularly injected with 0.5 mL NDV Pi/NJ/CH/4416/2016 strain of pigeon origin with HA potency of 5log2 . The pigeons in OE group drank the normal water and were challenged with the same NDV strain at the same dosage at the age of 42 days. Seven days after challenge, 3 pigeons were chosen from both KO and OE groups. The spleen samples were collected for paraffin-embedded tissue section preparation and for total RNA extraction to construct the transcriptome libraries. RNA-Seq was used to identify differentially expressed genes （DEGs） and to perform GO functional enrichment analysis as well as KEGG pathway enrichment analysis. Four randomly selected significant DEGs identified by RNA-Seq were verified by using qRT-PCR. [Result] The splenocytes of the pigeons in OE group had abnormally enlarged nuclei and white vacuoles, accompanied by a large number of granulocyte infiltration in splenic tissues, while those of the pigeons in KO group had many white vacuoles and minor granulocyte infiltration alone, and no abnormally enlarged splenocyte nuclei in splenic tissues were observed. A total of 374 DEGs were identified in the spleens of the pigeons in KO group by RNA-Seq, of which 112 were significantly up-regulated and 262 were significantly down-regulated. GO functional enrichment analysis demonstrated that 875 DEGs were enriched in 312 GO entries, of which 149 belonged to biological process, 33 belonged to cellular component, and 130 belonged to molecular function. KEGG pathway enrichment analysis revealed that 226 DEGs were enriched in 93 KEGG signaling pathways, including information transmission pathway, metabolic pathway, natural immunity related pathway, and apoptosis pathway. The qRT-PCR validation test showed that the relative mRNA abundance of the 4 randomly selected significant DEGs （LOC110360702, LOC110360688, SFRP5 and CHAD） had the same change trend as the RNA-Seq results. [Conclusion] Honeysuckle extract exerts protective role against NDV infection in pigeon by activating important physiological processes of host such as information transmission, metabolic regulation and immune response. The results obtained in this study provide a scientific basis for further investigation on the molecular mechanism of immune response to NDV infection in pigeon.

[Objective] This study was conducted to assess the effects of dietary supplementation of compound enzyme and probiotic preparations on growth performance, serum biochemical indices and antioxidant capacity, and small intestinal morphological development of AA broilers. [Method] A total of 480 one-day-old male AA broilers with similar weights were randomly assigned into a control group and 3 treatment groups （T1, T2, T3）. The control group fed a corn-soybean meal based diet, while the T1, T2 and T3 groups fed the same basal diets containing 0.2 g/kg compound enzyme preparation, 1 g/kg compound probiotic preparation, and 0.2 g/kg compound enzyme preparation+1 g/kg compound probiotic preparation, respectively. There were 6 replicates in each group and 20 broilers in each replicate. The feeding trial lasted for 42 days. The average daily feed intake （ADFI）, average daily gain （ADG）, and feed to gain ratio （F/G） at different growth stages （1-21 days of age, 22-42 days of age, 1-42 days of age) were calculated. On the 21^st and 42^nd day of the trial, blood samples were collected to determine the serum biochemical indices and antioxidant capacity. Samples of duodenum, jejunum and ileum were collected to prepare tissue sections. The villus height （VH） and crypt depth （CD） of each small intestinal segment was observed after HE staining, and the ratio of villus height to crypt depth （V/C） was calculated. [Result] ① Compared with the control group, significantly （P<0.05） higher weight at 21 days of age, ADFI and ADG at 1-21 days of age, and ADG at 1-42 days of age were observed in T1 and T3 groups; T1 group had significantly （P<0.05） increased ADFI at 22-42 days and 1-42 days of age, and had significantly （P<0.05) decreased F/G at 1-42 days of age; the F/G at 1-21 days, 22-42 days and 1-42 days of age in T2 group was significantly （P<0.05） reduced; T3 group had significantly （P<0.05） decreased F/G at 22-42 days and 1-42 days of age. The weight at 21 days of age as well as the ADFI and ADG at 1-21 days and 1-42 days of age in T1 and T3 groups were significantly （P<0.05） higher than those in T2 group. The F/G at 1-21 days and 22-42 days of age in T2 group was significantly （P<0.05） lower than that in T1 and T3 groups, and the F/G at 1-42 days of age in T2 group was significantly （P<0.05） lower than that in T1 group. ② Significantly （P<0.05） reduced serum TG content at 21 days and 42 days of age in T1, T2 and T3 groups was observed compared with the control group. T3 group had significantly （P<0.05） elevated serum TP content at 42 days of age than that of the control group and T2 group. T1 group had significantly （P<0.05） higher serum GLU content at 42 days of age than that of the other groups. ③ There were no significant （P>0.05） differences in serum antioxidant capacity at 21 days and 42 days of age among the 4 groups. ④ Compared with the control group, T1, T2 and T3 groups had significantly （P<0.05） lower CD and significantly （P<0.05） higher V/C of duodenum and ileum; T1 and T3 groups had significantly （P<0.05） increased VH of duodenum; T3 group had significantly （P<0.05） elevated VH of jejunum; T2 and T3 groups had significantly （P<0.05） reduced CD of jejunum. The VH and V/C of duodenum in T1 and T3 groups was significantly （P<0.05） higher than that in T2 group. The VH of jejunum in T3 group was significantly （P<0.05） higher than that in T1 and T2 groups. The CD of jejunum in T1 group was significantly （P<0.05） lower than that in T2 group. The CD of ileum in T3 group was significantly （P<0.05） lower than that in T1 group. [Conclusion] Exclusive or combined supplementation of compound enzyme and probiotic preparations in diet exhibited favorable effects on growth performance, serum biochemical indices and antioxidant capacity, and small intestinal morphological development of AA broilers. The combined supplementation showed a better comprehensive performance.

[Objective] This study was conducted to characterize the nutritional value, production performance and soil improvement effects of different varieties of forage grasses planted on floodplain in the Yinchuan section of the Yellow River in Ningxia Hui Autonomous Region. [Method] A total of 11 varieties of forage grasses were included in this study. The nutritional quality and production performance indexes of the forage grasses, as well as the soil nutrient indexes of the forage grass planting plots were determined and statistically compared. In addition, the correlation among these indexes were assessed. [Result] ①There were obvious variations in nutritional quality indexes among the 11 varieties of forage grasses. Zhongmu No.4, Bromus inermis and Festuca arundinacea had the highest contents of crude protein, crude fat and crude ash, respectively. Festuca arundinacea exhibited the lowest contents of crude fiber and ADF, and Zhongmu No.3 exhibited the lowest NDF content. The highest contents of total carbon and total nitrogen were observed in Elymus dahuricus and Zhongmu No.4, respectively, while those of calcium and phosphorus were observed in Ruide and Festuca arundinacea, respectively. ② The plots planted with the 11 varieties of forage grasses had significantly （P<0.05） decreased soil pH value and total salt content compared with those before planting. Except for the soil contents of total phosphorus and available phosphorus in selected forage grass planting plots, most soil nutrient indexes in the forage grass planting plots significantly （P<0.05） increased. The plots planted with Leymus chinensis or Agropyron mongolicum Keng had higher soil contents of total nitrogen, organic matter and alkaline hydrolysis nitrogen. The Leymus chinensis planting plot had the highest soil contents of available phosphorus and available potassium. The highest soil content of total phosphorus was observed in the Agropyron mongolicum Keng planting plot. ③ Except for Elymus dahuricus with a lower plant height, there were no significant （P>0.05） differences in plant height among the other 10 varieties of forage grasses. Elytrigia elongata, Agropyron mongolicum Keng, Zhongmu No.4 and Zhongmu No. 3 had higher grass yield. ④ Correlation analysis demonstrated that grass yield had varying degrees of positive or negative correlation with some indexes of nutritional quality of forage grasses and some soil nutrient indexes of the forage grass planting plots. Principal component analysis showed that the comprehensive evaluation ranking of the 11 varieties of forage grasses was as follows: Leymus chinensis>Agropyron mongolicum Keng>Bromus inermis>Puccinellia distans>Elytrigia elongata>Zhongmu No.4>Elymus dahuricus>Festuca arundinacea>Qishi No.2>Zhongmu No.3>Ruide. [Conclusion] Leymus chinensis, Agropyron mongolicum Keng, Bromus inermis, Puccinellia distans and Elytrigia elongata had better comprehensive performance when planting on floodplain in the Yinchuan section of the Yellow River, and had the potential to be the mainly promoted varieties of forage grasses and used for soil improvement in the Yellow River floodplain.

[Objective] The aim of the present study was to assess the effects of dietary supplementation of Chinese herbal medicines on nutrient apparent digestibility, serum biochemical indices and cecal microflora of broilers. [Method] The feeding experiment was carried out with a one-factor completely randomized design. A total of 576 one-day-old male healthy Kebao 505 white-feathered broilers with similar weights were randomly allocated to 8 groups （A-H）. There were 6 replicates in each group and 12 broilers in each replicate. Group A served as a control and fed the basal diet, and the groups B-H fed the same basal diets adding 0.48 g/kg florfenicol, 1.5% Radix isatidis, 1.5% Folium isatidis, 1.5% Indigo naturalis, 0.75% Radix isatidis+0.75% Folium isatidis, 0.75% Radix isatidis+0.75% Indigo naturalis, and 0.75% Folium isatidis+ 0.75% Indigo naturalis, respectively. The feeding experiment which lasted for 42 days was composed of an early stage （1-21 days of age） and a late stage （22-42 days of age） according to the ingredient compositions and nutrition levels of the basal diets. The fecal samples of the broilers at 39-41 days of age were collected to measure the apparent digestibility of major nutrients. The blood samples of the broilers at 42 days of age were collected to determine the biochemical indices. The cecal chyme samples of the broilers in groups A, B and F at 42 days of age were collected to evaluate the microbial diversity and abundance. [Result] Group F had significantly （P<0.05） higher apparent digestibility of nitrogen than the other groups except for group A, had significantly （P<0.05） increased apparent digestibility of dry matter than the other groups except for groups B and G, had significantly （P<0.05） elevated apparent digestibility of energy than groups B, C, D, E and H, had significantly （P<0.05） raised apparent digestibility of calcium than the other groups, and had significantly （P<0.05） improved apparent digestibility of phosphorus than groups C, D, E, G and H. No significant （P>0.05） differences in the serum contents of albumin, total protein, glucose, triglyceride and total cholesterol were observed among the different groups. F group had a significantly （P<0.05） higher Chao1 index of cecal microflora than group A. Firmicutes and Bacteroidetes were the dominant bacterial phyla in cecal chyme samples in groups A, B and F, and the relative abundance of these two bacterial phyla in groups A, B and F were 69.49%, 70.26%, 81.45% and 27.52%, 25.04%, 15.47%, respectively. In addition, Faecalibacterium, Ruminococcaceae_UCG-014, Barnesiella, Bacteroides and Lactobacillus were the bacterial genera that possessed the higher relative abundance. Group F had significantly （P<0.05） increased relative abundance of Firmicutes and significantly （P<0.05） decreased relative abundance of Bacteroidetes than groups A and B. Group B had significantly （P<0.05） reduced relative abundance of Bacteroidetes than group A, and had significantly （P<0.05） elevated relative abundance of Cyanobacteria than groups A and F. Group F had significantly （P<0.05） decreased relative abundance of Actinobacteria than group B. The relative abundance of Faecalibacterium, Barnesiella and Bacteroides in group F was significantly （P<0.05） lower than that in groups A and B, while the relative abundance of Lactobacillus and Ruminococcus_torques_group in group F was significantly （P<0.05） higher than that in groups A and B. The relative abundance of Faecalibacterium and Lactobacillus in group B was significantly （P<0.05） lower than that in group A. There were no significant （P>0.05） differences in the composition of cecal microflora among groups A, B and F. [Conclusion] Dietary supplementation of 0.75% Radix isatidis and 0.75% Folium isatidis exhibited improving effects on the apparent digestibility of major nutrients as well as the diversity and abundance of cecal microflora in broilers.

[Objective] The aim of the present study was to characterize the amino acid profiles in free-grazing Alagxa white cashmere goat and Mongolian sheep meat from Alagxa League, Inner Mongolia. [Method] A total of 137 mutton samples including biceps femoris, longissimus dorsi muscle and intercostal muscle were collected from Alagxa white cashmere goat and Mongolian sheep reared in Alagxa Left Banner, Alagxa Right Banner and Ejin Banner of Alagxa League. The contents of 17 kinds of amino acids in mutton were assessed in accordance with the Determination of Amino Acids in Food in National Food Safety Standards （GB 5009.124—2016）. Chemometric discrimination and descriptive statistical analysis methods were applied to compare the differences in amino acid profiles in mutton from different species and parts. [Result] Orthogonal partial least squares discriminant analysis （OPLS-DA） achieved an higher separating capacity in amino acid contents in mutton from different species and parts. The presence of all the tested amino acids were detected in mutton from both species, including 7 kinds of essential amino acid （EAA） for human. There were no significant （P>0.05） differences in the contents of all the tested amino acids between the mutton from the two species, and the similar contents of total amino acid （TAA）, EAA and non-essential amino acid （NEAA） were observed within the two species. There were significant （P<0.05） differences in most of the amino acid contents in mutton from the three parts, and significant （P<0.05） differences in the contents of TAA, EAA and NEAA were observed among different parts as well. The characteristic amino acids of intercostal muscle samples were Gly, Pro and Ala, while His, Tyr, Gly, Lys, Ala, Phe and Met were the potentially important marker amino acids for discriminating different parts of mutton. The ratios of EAA to TAA （EAA/TAA） in the mutton from both species and three parts were all around 40%, and those of EAA to NEAA （EAA/NEAA） were all above 60%, which were in line with the recommended EAA/TAA and EAA/NEAA of ideal protein by FAO/WHO. [Conclusion] The amino acid profiles in different parts of free-grazing Alagxa white cashmere goat and Mongolian sheep meat from Alagxa League was preliminarily characterized in this study. Mutton from both species were abundant in amino acid composition and content, and had high nutritional value.

[Objective] The aim of the present study was to clarify the infection status of Theileria in beef cattle in the Ninth Division of the Xinjiang Production and Construction Corps （hereinafter referred to as the Ninth Division）. [Method] A total of 118 blood samples were collected with anticoagulation tubes from beef cattle reared in the large-scale farms or scatter-feed households in the 161 （n=48）, 163 （n=22）, 164 （n=25） and 165 （n=23） Regiments of the Ninth Division, respectively. Among them, 48 samples were collected from the confined beef cattle and the remaining 70 samples were collected from the free-range beef cattle. The whole genomic DNA of the blood samples were extracted, and PCR assay was used to detect the presence of T. annulata, T. orientalis and T. sinensis with the specially designed primers. The species of Theileria were identified by sequence alignment, and the phylogenetic tree was constructed for genetic evolution analysis. The χ² test was employed to assess the differences in the infection rate of Theileria in beef cattle at different sampling sites and under different rearing modes. [Result] PCR detection showed that among the 118 blood DNA samples of beef cattle, 82 samples were positive for Theileria, with an overall infection rate of 69.49% （82/118）. All Theileria positive samples had T. orientalis alone, while T. annulata and T. sinensis were absent. The infection rates of Theileria in beef cattle in the 161, 163, 164 and 165 Regiments of the Ninth Division were 29.17% （14/48）, 95.45% （21/22）, 96.00% （24/25） and 100% （23/23）, respectively. There was an extremely significant difference in the infection rates of Theileria in beef cattle at different sampling sites （χ²=62.195, P<0.01）. A higher infection rate （97.14%, 68/70） of Theileria was observed in the free-range beef cattle, while a lower one （29.17%, 14/48） was observed in the confined beef cattle. The infection rates of Theileria in beef cattle under different rearing modes were extremely significantly different （χ²=62.061, P<0.01）. Among the 82 sequences obtained, 78 had 100% homology with the MPSP gene sequence of a T. orientalis isolate from cattle in Xinjiang Uygur Autonomous Region （GenBank accession number: ON462019）, and the sequence type was designated as TSE1. The remaining 4 sequences had 100% homology with the MPSP gene sequence of another T. orientalis strain of cattle origin in Xinjiang Uygur Autonomous Region （GenBank accession number: ON462018）, and the sequence type was designated as TSE2. The phylogenetic analysis demonstrated that the identified TSE1 and TSE2 sequences in present study were clustered with T. orientalis of cattle origin in Xinjiang Uygur Autonomous Region. [Conclusion] The species of Theileria prevailed in beef cattle in the Ninth Division of the Xinjiang Production and Construction Corps was T. orientalis. The free-range beef cattle had a higher infection rate of Theileria, suggesting the detection of Theileria in the free-range beef cattle herd should be strengthened.

[Objective] This study was conducted to assess the effects of ellagic acid on growth performance, antioxidant function and intestinal barrier function in mice fed aflatoxin-containing diets. [Method] A total of 30 healthy female Kunming mice weighted 18 to 22 g were randomly assigned into a control group, a toxin group or an ellagic acid treatment group, with 10 mice in each group. The control group fed a basal diet, the toxin group fed the basal diet containing 250 μg/kg aflatoxin, and the ellagic acid treatment group fed the basal diet supplemented with 250 μg/kg aflatoxin and 100 mg/kg ellagic acid. The feeding experiment lasted for 35 days. The mice were individually weighed at the beginning and end of the experiment, and the weight gain were calculated. At the end of the experiment, the blood samples of the mice were collected with ophthalmectomy. The serum antioxidant indexes such as total superoxide dismutase （T-SOD） activity, total antioxidant capacity （T-AOC） and malondialdehyde （MDA） content as well as the intestinal barrier function indexes such as diamine oxidase （DAO） activity and D-lactic acid content were determined by using ELISA assay. The jejunal tissue samples of the mice were collected to prepare paraffin section. The morphological structure of jejunal mucosa, jejunal villus height and jejunal crypt depth were observed with HE staining, and the ratio of villus height to crypt depth was calculated. [Result] The final body weight and the weight gain of toxin group were extremely significantly （P<0.01） lower than control group. While the final body weight of ellagic acid treatment group was not significantly （P>0.05） different from toxin group, the weight gain of ellagic acid treatment group was extremely significantly （P<0.01） higher than toxin group. Toxin group had significantly （P<0.05） decreased serum T-AOC activity and extremely significantly （P<0.01） reduced serum T-SOD activity in comparison to toxin group. Ellagic acid treatment group had extremely significantly （P<0.01） elevated serum T-SOD activity compared with toxin group, while no significant （P>0.05） difference in serum T-AOC activity was found between these two groups. An extremely significantly （P<0.01） higher serum MDA content was observed in toxin group than control group, and an extremely significantly （P<0.01） lower serum MDA content was observed in ellagic acid treatment group than toxin group. Toxin group had extremely significantly （P<0.01） higher serum DAO activity and D-lactic acid content compared with control group. Ellagic acid treatment group had significantly （P<0.05） reduced serum DAO activity compared with toxin group,while no significant （P>0.05） difference in serum D-lactic acid content was found between these two groups. The jejunal villi and crypt of the mice in control group exhibited complete morphology, and no abnormal pathological changes were observed. Serious pathological damages were observed in jejunal tissues of the mice in toxin group：the arrangement of jejunal villi was neither neat nor tight, the intervillous space enlarged and even break, and the arrangement of jejunal crypt was also not neat. The jejunal villus height and the ratio of villus height to crypt depth of toxin group was extremely significantly （P<0.01） decreased compared with control group, while no significant （P>0.05） difference in jejunal crypt depth was found between these two groups. The mice in ellagic acid treatment group exhibited alleviated pathological damages in jejunal tissues compared with toxin group：the morphology of jejunal mucosa was basically restored to normal, the villi breakage was ameliorated, and the jejunal crypt arranged more neatly. The ellagic acid treatment group had extremely significantly （P<0.01） increased jejunal villus height and the ratio of villus height to crypt depth than toxin group, while no significant （P>0.05） difference in jejunal crypt depth was found between these two groups. [Conclusion] Ellagic acid alleviates the damages induced by aflatoxin in mice via inhibiting the body weight reduction, enhancing serum antioxidant function and improving jejunal mucosa barrier function.

[Objective] The aim of the present study was to characterize the activity and proliferation of spermatogonial stem cells （SSCs） from testes of Boer goats at different months of age during in vitro culture. [Method] Testes of Boer goats at 1, 3, 5 and 58 months of age were sampled, and the development of them was observed by histological method. The testicular tissues from goats at different months of age were separated to single cell by three-step enzyme digestion method. The total number of digestive cells and the number of dead cells was observed by trypan blue staining. The SSCs were purified with differential adhesion method and cultured for 10 days. The number of Thy-1⁺ cells in suspension before purification, after purification and cultured for 10 days was determined by flow cytometry. After cultured for 10 days, the SSCs clones were identified by alkaline phosphatase staining, and the number and area of clones formed by SSCs from testes of goats at different months of age were statistically measured. [Result] Testicular histological observation demonstrated that goats aged 1 month had the least number of germ cells in lumen of contorted seminiferous tubule, germ cells of all levels gradually developed with the increase of months of age, while seminiferous epithelium of goats aged 58 months was evidently degraded. After three-step enzyme digestion, the highest total number of testicular cells obtained before and after purification was observed in goats aged 5 months, which was significantly （P<0.05） higher than that in goats aged 1 month. There was no significant （P>0.05） difference in survival rate of testicular cells before and after purification for goats at different months of age. Among pre- and post-purification testicular cells and purified SSCs cultured for 10 days, the highest proportion of Thy-1⁺ cells in the total number of testicular cells was found in goats aged 1 month, which was significantly （P<0.05） higher than that in goats aged the other months. After 10 days of culture, the SSCs clones from testes of goats at different months of age were positive for alkaline phosphatase. The average number of SSCs formed clones from testes of goats aged 1 month was significantly （P<0.05） higher than that of goats aged the other months, while no significant （P>0.05） difference in average area of SSCs formed clones among goats at different months of age was observed. [Conclusion] Boer goats aged 5 months had the highest total number of cells in testes. Those aged 1 month had the lowest total number of cells in testes, while had the highest activity and proliferation efficiency of SSCs.

[Objective] This study was conducted to investigate the effects of feeding corn straw treated with different methods as roughage on methane emission and rumen function in beef cattle. [Method] Seventeen-month-old healthy Grassland Red cattle （n=3） and Yanbian Yellow cattle （n=3） with an average weight of （375±5） kg were selected. The feeding trial with two-factor experimental design was composed of two stages and each had a pre-feeding period of 15 days and a formal-feeding period of 3 days. In the first stage, Grassland Red cattle fed corn straw silage as roughage （QH group） and Yanbian Yellow cattle fed dry corn straw as roughage （JY group）. In the second stage, Grassland Red cattle fed dry corn straw as roughage （JH group） and Yanbian Yellow cattle fed corn straw silage as roughage （QY group）. The initial and final weights as well as feed intake of the experimental cattle were recorded, and the average daily gain and dry matter intake was calculated. An open reflux respiratory calorimetry device for large animal were used to determine the methane emission. Rumen fluid samples were collected to evaluate pH value as well as the contents of ammonia nitrogen, rumen microbial protein, total volatile fatty acids, acetic acid, propionic acid, and butyric acid. In addition, the rumen microflora was characterized using 16S rDNA high-throughput sequencing, and the rumen fluid metabolites were assessed using non-targeted metabolomics. [Result] ① Yanbian Yellow cattle had extremely significantly （P<0.01） higher final weight and average daily gain as well as extremely significantly （P<0.01） lower dry matter intake in comparison to Grassland Red cattle, while no significant （P>0.05） difference in the methane emission was observed between the two cattle breeds. QH and QY groups had extremely significantly （P<0.01） increased final weight, average daily gain and dry matter intake as well as extremely significantly （P<0.01） decreased methane emission in comparison to JH and JY groups. ②The rumen fermentation parameters of Grassland Red cattle were not significantly （P>0.05） different from those of Yanbian Yellow cattle. Compared with JH and JY groups, QH and QY groups exhibited extremely significantly （P<0.01） reduced rumen fluid pH value, contents of ammonia nitrogen, acetic acid and butyric acid, and ratio of acetic acid to propionic acid, while exhibited extremely significantly （P<0.01） elevated contents of rumen microbial protein, total volatile fatty acids, and propionic acid. ③ Firmicutes, Proteobacteria and Bacteroidetes were observed as the dominant rumen microbial phyla in the four groups, with total relative abundance from 73.75% to 81.22%. The cattle breeds, corn straw treatment methods and the interaction between these two factors had no significant （P>0.05） effects on the relative abundance of rumen microflora at phylum level. Compared with JH and JY groups, extremely significantly （P<0.01） higher relative abundance of Succiniclasticum, Butyrivibrio and Ruminococcus as well as extremely significantly （P<0.01） lower relative abundance of Clostridiaceae_Clostridium and Prevotella was observed in QH and QY groups. The cattle breeds, corn straw treatment methods and the interaction between these two factors had no significant （P>0.05） effects on the relative abundance of rumen microflora at genus level. ④ A total of 525 secondary differential metabolites were screened from rumen metabolites of different groups, among which 10 were significantly different. Quinolinic acid, fumaric acid, cortisone, L-glutamic acid, phenyllactate, L-carnitine, and catechol were significantly enriched in 9 pathways. Fumaric acid was significantly enriched in tryptophan metabolism, central carbon metabolism in cancer, arginine biosynthesis, and phenylalanine metabolism pathways. The correlation analysis between the relative abundance of rumen microflora at genus level and the concentrations of differential metabolites in rumen fluid showed an extremely significantly （P<0.001） negative correlation between the concentration of fumaric acid and the relative abundance of Prevotella. [Conclusion] Feeding corn straw silage as roughage was able to effectively control the methane emission, increase the daily weight gain, ameliorate the rumen fermentation function, and decrease the relative abundance of Prevotella in rumen in beef cattle. In addition, the lower methane emission of the beef cattle fed corn straw silage as roughage was attributed to the elevated concentration of fumaric acid in rumen fluid.

[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 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 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] 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] 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] 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.

Ventilation in animal housing refers to the exchanging process of internal and external air, which is crucial for maintaining good air quality as well as regulating temperature and humidity in animal housing, and for reducing the risk of respiratory diseases in animals. The primary ventilation patterns in animal housing include natural and mechanical ventilation. Natural ventilation relies on natural forces and is suitable for open animal housing, while mechanical ventilation controls air movement within housing using machinery equipment, offering more flexibility. The factors such as animal species, layout and structure of animal housing, climate and geographical location should be taken into account in selection of ventilation patterns. The comfort of animal housing environment directly impacts the health status and production performance of animals. High temperature and high humidity environment may cause heat stress in animals, and further affects their feed intake, growth and immune function. Accordingly, scientific and reasonable ventilation management is of great significance for maintaining health and improving production efficiency of animals. This paper introduced the commonly used ventilation patterns in animal housing, expounded the impacts of different ventilation patterns on environmental factors, and reviewed the research progress on the effects of ventilation patterns on animals′ physiological and biochemical parameters and production performance, in hoping to provide theoretical basis for the design and construction of ventilation systems in animal housing.

The use of biological feed as an antibiotic alternative has gained a lot of attention in light of the antibiotic ban in animal feed. Biological feed offers benefits including improving feed quality, enhancing animal production performance, boosting animal immunity and regulating animal gut microbiota, exhibiting an increasing market acceptance. This paper introduced the definition and classification of biological feed, summarized the research progress on the application of biological feed in cattle, sheep and pig production taking fermented feed and bacterium and enzyme synergistic fermented feed as examples, analyzed the problems in the current application of biological feed, and put forward relevant suggestions, in hoping to provide references for the development and application of biological feed.

During the process of silage, the anaerobic environment can not be completely achieved by fermentation of silage raw materials alone, which not only results in the increase of pH value and ammonia nitrogen content as well as the decrease of lactic acid content in silage, but also may lead to the fermentation of undesirable microorganisms, affecting the effect of silage. To reduce the loss of nutrients during the fermentation process of silage and to improve the fermentation quality and nutritional value of silage, additives are commonly used in silage preparation. The frequently used additives for silage mainly include the following four types: bacterial inoculants, enzyme preparations, fermentation inhibitors and non-protein nitrogen. Different types of additives improve the fermentation quality of silage through varied ways, further ameliorating the nutritional value and feeding effect of silage. This paper reviewed the research progress on the impacts of different types of additives on sensory quality, fermentation quality and microbial diversity of silage, in hoping to provide a reference for the scientific selection of silage additives.

Fermented Chinese herbal medicine combines the pharmacological effects of Chinese herbal medicine with the health benefits of probiotics. During the fermentation process, Chinese herbal medicine offers nutrients to microorganisms and promotes their growth, while the enzymes and metabolites produced by microorganisms stimulate the release of effective ingredients in Chinese herbal medicine, reduce the toxicity of derivative preparations, and also synthesize novel active ingredients to enhance the drug efficacy. The fermentation process also decompose the active macromolecules or polymers into small molecules, facilitating transmembrane transport and aiding in the absorption of active substances by the body. In addition, some microorganisms in fermented Chinese herbal medicine inhibit the proliferation of pathogenic bacteria and work synergistically with Chinese herbal medicine to jointly combat pathogens. Under the background of reducing antibiotics use and replacing antibiotics, fermented Chinese herbal medicine, as a type of green feed additive, has great utilization value and prospects in animal husbandry. This paper summarizes the research progress on the characteristics of fermented Chinese herbal medicine and application in animal production, in hoping to provide references for the further development and utilization of fermented Chinese herbal feed additives.

[Objective] The purpose of this study was to investigate the degradation effect of potassium ferrate combined with hydrogen peroxide on florfenicol in water. [Method] A 4-factor 5-level orthogonal test was conducted using the molar ratio of potassium ferrate to florfenicol, the molar ratio of hydrogen peroxide to potassium ferrate, the pH value of the reaction system, and the reaction duration as the factors. The concentration of florfenicol was determined by high performance liquid chromatography, and the degradation rate of florfenicol was used as an evaluation index to determine the optimal degradation conditions. [Result] The optimal degradation conditions obtained from the orthogonal test were as follows: the molar ratio of potassium ferrite to florfenicol was 45∶1, the molar ratio of hydrogen peroxide to potassium ferrite was 1∶1, the pH value of the reaction system was 7, and the reaction duration was 45 min. [Conclusion] The combination use of potassium ferrite and hydrogen peroxide could effectively degrade florfenicol in water.

Plant essential oil is a natural mixture of volatile and aromatic compounds extracted from plants, with biological activities such as antimicrobial, antioxidant, anti-inflammatory and immunomodulatory properties. At present, research on the application of plant essential oil in chicken production mainly focuses on improving growth performance, anti-oxidant stress and regulating intestinal development. This paper introduced the physicochemical properties and biological activities of plant essential oil, and reviewed the research progress on the application of plant essential oil as feed additives in chicken production, in hoping to provide reference for the development of plant essential oil preparations and their scientific application in chicken production.

With the continuous development of social economy and the steady improvement of people′s living standards, the public′s attention to the quality and safety of livestock products has also increased. The quality of livestock products reflects the development level of the animal husbandry industry, and the issue of livestock products quality and safety has become one of the critical issues restricting the healthy development of the animal husbandry industry. The livestock products quality and safety traceability system can trace the origin of livestock products and realize the sharing of information throughout the whole process from farm to fork. With the help of the livestock products quality and safety traceability system, the producers can achieve precise feeding and management as well as improve their breeding efficiency, the regulators can achieve precise supervision and improve their management efficiency, and the consumers can achieve worry-free consumption and improve their satisfaction. Accelerating the construction and application of the livestock products quality and safety traceability system is conductive to ensure the quality and safety of livestock products and promote the improvement of quality and efficiency of animal husbandry production. This paper introduced the application status of the livestock products quality and safety traceability system, analyzed the main problems in the application of the system, and put forward countermeasures and suggestions to accelerate the promotion of the system, in hoping to provide references for enhancing the supervision efficiency of livestock products quality and safety as well as helping the high-quality development of the animal husbandry industry.

As a fundamental link of the modern grassland governance system, digitization of grassland ecological production is crucial for preserving ecological balance, increasing productivity, and fostering the transformation and upgrading of the pastoral economy. Currently, although digital technology is being widely used in monitoring and management of grassland ecological production at all levels, its overall development and implementation is still lagging behind. With a particular focus on the digitization process of grassland ecology and production activity, this paper analyzed the development status, main accomplishments and primary problems in this field at both the national and Inner Mongolia Autonomous Region levels. Furthermore, a series of countermeasures on the digital development of grassland ecological production were made from the perspective of national strategy in response to the numerous shortcomings of the current digital construction of grassland ecology, in hoping to lay a strong technological foundation for the realization of the ecological civilization construction goal of ′green mountains and clear waters are invaluable assets′, as well as for the development of new quality productive forces in grassland.

The irrational use or even abuse of antibiotics in animal production not only seriously endangers the health of human beings and animals, but also brings negative effects to social and economic development. Antibiotics were once used as feed additives to promote growth and improve feed conversion of livestock and poultry. Announcement No. 194 issued by the Ministry of Agriculture and Rural Affairs of China in 2019 required that the feed manufacturers were prohibited to produce commercial feed containing growth-promoting drug feed additives （except for traditional Chinese medicine） since 1 July 2020. Therefore, it is urgent to research and develop new green feed additives replacing antibiotics. In recent years, plant-derived feed additives have become a popular alternative to antibiotics. Studies have shown that plant extracts possessed the ability to improve growth and reproductive performance, regulate intestinal bacterial flora, enhance immune function, as well as prevent and control diseases in animal production. In this paper, the research progress on the application of plant extracts as substitutes for antibiotics in animal production was reviewed, in hoping to provide references for the promotion and application of plant-derived feed additives in animal production.

Heat stress affects the milking performance of lactating dairy cows through various routes, such as reducing feed intake, altering energy metabolism pattern, activating immune system and causing inflammation, and influencing mammary gland development and function. Alleviating measures against heat stress in dairy farms are usually taken from the aspects of nutrition, management and genetics, while the effect is limited. Understanding the potential mechanisms by which heat stress causes reduction in milk production in lactating dairy cows is crucial for controlling milk production losses resulted from heat stress. This paper reviewed the research progress on the influence mechanisms of heat stress on the milking performance of lactating dairy cows, in hoping to provide references for the scientific formulation of heat stress alleviating measures in dairy cow production.

Cryptosporidium is an important genus of parasitic protozoa and is the causative agent for cryptosporidiosis. Cryptosporidium is capable of infecting various hosts （human, livestock and poultry） through water and food, causing symptoms such as diarrhea and even death. It not only brings huge economic losses to livestock and poultry farming, but also poses a serious threat to public health and safety. At present, there are no effective vaccines or specific drugs against cryptosporidiosis. Accordingly, the epidemiological investigation of this disease is particularly critical. In this paper, we reviewed the research progress on infection rate, species distribution, infection risk factors of Cryptosporidium in pig herds in China, and assessed the zoonotic risk, in hoping to provide references for the effective prevention and control against pig cryptosporidiosis.

[Objective] This study aimed to assess the effects of different saline-alkali stresses on seed germination and seedling growth of forage triticale（× Triticosecale Wittmack）. [Method] The solutions of NaCl, Na₂SO₄, Na₂CO₃ and NaHCO₃ were used to simulate the saline-alkali stress environments, with Na⁺ concentrations set at 0 （CK）, 50, 75, 100, 150 and 200 mmol/L for each solution. Seed germination experiments were conducted to evaluate the change patterns of germination percentage （Gp）, germination index （Gi）, mean germination time （MGT）, seedling vigor index （SVI）, embryonic root length and embryonic bud length of forage triticale under the stresses induced by different types of saline-alkali and concentrations of Na⁺, to reveal the response characteristics of seed germination and seedling growth to different saline-alkali stresses. [Result] Different types of saline-alkali, concentrations of Na⁺ and their interactions all had extremely significant （P<0.01） impacts on Gp, Gi, MGT, SVI, embryonic root length and embryonic bud length of forage triticale. With the increase of Na⁺ concentrations, Gp, Gi, SVI, embryonic root length and embryonic bud length of forage triticale decreased, while MGT elevated. Under the same Na⁺ concentration, forage triticale seed exhibited higher tolerance to neutral salt stress than alkaline salt stress. [Conclusion] With the increase of Na⁺ concentrations, the inhibitory effects of different saline-alkali stresses on seed germination and seedling growth of forage triticale enhanced. Alkaline salt posed stronger inhibitory effect than neutral salt. Forage triticale seed showed certain tolerance to the stress induced by the lower Na⁺ concentrations, indicating that it could be planted on the mild saline-alkali soils in China.

[Objective] The aims of the present study were to review and sort out the research progress and experience in agricultural and livestock product production base construction in China and abroad, and to summarize the enlightenment for Inner Mongolia in constructing the national important agricultural and livestock product production base. [Method] Literature review method was used to analyze the main research contents and achievements in agricultural and livestock product production base construction in China and abroad, and the corresponding experience and practice in this field were summarized. Furthermore, the current situation and restricting factors of agricultural and livestock product production base construction in Inner Mongolia were assessed, and relevant suggestions for the high-quality construction of national important agricultural and livestock product production base were proposed. [Result] The research conducted by scholars in China and abroad has demonstrated that the agricultural and livestock product production base construction is able to effectively promote the regional economic development, optimize the structure of agricultural and animal husbandry industries, and improve the quality of agricultural and livestock products. The United States, Japan, Australia and some European countries have established well-known agricultural and livestock product production bases or industrial belts worldwide. Some regions in China have also combined their resource endowments to construct agricultural and livestock product production bases with local characteristics. These construction experiences have reference significance for Inner Mongolia. Although Inner Mongolia has achieved positive results in constructing the national important agricultural and livestock product production base, it still faces some problems such as natural resource constraints, weak infrastructure construction in agricultural and animal husbandry industries, inadequate scientific and technological support and innovation capabilities, and insufficiently extended animal husbandry industry chain. Based on the experience in agricultural and livestock product production base construction in China and abroad, and starting from the actual situation in Inner Mongolia, this paper proposes some countermeasures and suggestions as follows：strengthening the infrastructure construction of agricultural and livestock product production base, enhancing the production capacity of agricultural and livestock products, accelerating the construction of new-type management systems, promoting the integrated development of agricultural and animal husbandry industries, strengthening the construction of scientific and technological service systems, promoting the high-quality development of agricultural and animal husbandry industries, improving the support policies and guarantee measures, and forming a green development system. [Conclusion] The results obtained in this study provide references for the high-quality construction of national important agricultural and livestock product production base in Inner Mongolia, and for the promotion of stable and safe supply of grain and important agricultural and livestock products.

Selenium is one of the essential trace elements for animals, which is involved in a series of biological processes such as anti-oxidation, immunity, reproduction and intestinal bacterial flora regulation. In recent years, among the selenium preparations from different sources, nano-selenium has attracted the attention of animal nutrition researchers both in China and abroad due to such advantages as low toxicity, high bio-availability, good safety and strong antioxidant property, becoming a hotspot in the research field of feed additives. This paper summarized the nature and characteristics, absorption and metabolism mechanism, and biological functions of nano-selenium, and reviewed the research progress on its application in animal production, in hoping to provide references for the development of nano-selenium feed additives and their scientific application in animal production.

Quaternary ammonium salt-based disinfectants （QASDs） are chemical disinfectant agents prepared with disinfectant quaternary ammonium compounds. They are cationic disinfectants with strong antibacterial activity and have diverse uses in a variety of fields such as public places, food processing, aquaculture and healthcare, playing a critical role in preventing the spread of environmental pathogenic microorganisms. Due to the irrational use of QASDs, bacteria have gradually become resistant to them, and the detection rate of resistant bacteria has increased substantially. The emergence of disinfectant resistance genes has exacerbated the mutual transmission of the QASDs resistant bacteria at the human-animal-environment interface. Bacteria can develop varying degrees of resistance to QASDs through different mechanisms such as generating biofilms, altering cell membrane permeability, active efflux systems, synthesizing degradative enzymes, changing target sites of action, and acquisition of genetic elements, posing a serious threat to human health and ecological environment. In this paper, the research progress on bacterial resistance to QASDs as well as corresponding detection methods and possible underlying mechanisms were reviewed to further clarify the influencing factors of bacterial resistance to QASDs, in hoping to provide references for scientific cognition and rational use of QASDs as well as effective control of bacterial resistance to QASDs.

[Objective] The aim of the present study was to characterize the molecular epidemiology and genetic variation of porcine reproductive and respiratory syndrome virus （PRRSV） in Guangxi Zhuang Autonomous Region. [Method] A real-time fluorescent RT-PCR kit for universal detection of PRRSV was utilized to detect the presence of PRRSV in a lung tissue sample collected from the clinically infected pig on a farm in Guangxi Zhuang Autonomous Region. Subsequently, a dual real-time fluorescent RT-PCR kit specific for the PRRSV American classic strain and NADC30-like PRRSV strain were employed to further identify the sample. The GP5 gene was amplified by PCR, and a homologous comparison was conducted between the obtained nucleotide sequence by sequencing and the GP5 gene sequences of both domestic and international PRRSV reference strains retrieved from the GenBank database. Additionally, a phylogenetic tree was constructed. The amino acid sequences derived from the GP5 gene were analyzed by sequence alignment. [Result] The sample was identified as NADC30-like PRRSV positive and designated as GXYL strain. Homologous analysis of the GP5 gene nucleotide sequences indicated that GXYL strain exhibited 61.9% to 93.2% similarity with both domestic and international PRRSV reference strains, sharing the highest homology with PRRSV NADC30 strain from the United States and the lowest homology with PRRSV LV strain of European type. Furthermore, phylogenetic tree analysis based on GP5 gene sequences placed GXYL strain within a branch alongside NADC30-like strains from China and NADC30 strains from the United States, indicating close relatedness among them within a larger branch containing other American type strains. Amino acid comparison analysis derived from GP5 gene sequences identified 7 mutation sites within GXYL strain, among which 2 sites were located at epitope A, 1 site was located at epitope B, and 4 sites were located at signal peptide region. No amino acid insertions or deletions were found. [Conclusion] GXYL strain is a NADC30-like PRRSV strain, suggesting that the surveillance of prevalence and genetic variation in PRRSV should be strengthened in this region.

[Objective] The aims of the present study were to isolate and identify Pasteurella multocida （Pm） from sheep, and to assess the biological characteristics of the isolate. [Method] On site dissection was performed on sheep with typical respiratory disease symptoms from a family farm in Togtoh County, Hohhot City, Inner Mongolia Autonomous Region. The pathological changes of the main respiratory organs and spleen were observed and the pathological sections of lung tissue were prepared. Lung tissue sample was aseptically collected for bacterial isolation and culture. After phenotypical identification, molecular biological identification and capsular serotype identification of the isolated strain were performed. PCR assay was used to detect the virulence genes. Disc diffusion method was used to test the sensitivity of the isolated strain to 11 antimicrobial agents. The pathogenicity of the isolated strain to mice was evaluated using intraperitoneal injection method. [Result] The diseased sheep had adhesions of the lungs to the pleura and pericardium, necrotic lesions in the lung tissues, enlarged lymph nodes in the hilum of the lung, and bleeding sites in the spleen. After isolation and purification, one bacterial strain was obtained and designated as 2021-TX-06. This strain appeared as a tiny, circular and white colony with slight protrusion on TSA medium containing 5% horse serum. It was a Gram negative bacterium that conformed to the biochemical characteristics of Pm and was capable of fermenting and utilizing mannitol, sorbitol, trehalose, xylose and glucose. After 16S rDNA PCR amplification and sequence alignment, the 2021-TX-06 strain was identified as Pm. Following capsular serotyping, it was identified as capsular serotype D, carrying 15 virulence genes such as ptfA, fimA, Fur, etc. It was sensitive to the antimicrobial agents including tetracycline, ceftriaxone, gentamicin, polymyxin B, and resistant to norfloxacin, enrofloxacin, and chloramphenicol. Seventy-two hours after the intraperitoneal injection with 5 × 10⁸ CFU/mL bacterial suspension of 2021-TX-06 strain, a 100% mortality rate was observed in the experimental group mice. A strain consistent with the challenging strain was recovered from the lungs of the dead mice. [Conclusion] A Pm prevalent strain belonging to capsular serotype D was isolated from the lung tissue of sheep with typical respiratory disease symptoms. This strain harbored multiple virulence genes, showed resistance to some antimicrobial agents, and had strong pathogenicity to mice.

[Objective] This study aimed to assess the effects of 'QiYouNeng', a preparation of Astragalus membranaceus extracts （whole composition）, on immune function and pathological damage of the weaned piglets infected with porcine reproductive and respiratory syndrome virus （PRRSV）. [Method] A total of 32 PRRSV-positive 28-day-old weaned piglets were selected and randomly divided into Groups Ⅰ, Ⅱ, Ⅲ and Ⅳ, with 8 piglets in each group. The experiment period was 42 days. In the first and fifth weeks of the experiment, Groups Ⅰ, Ⅱ, Ⅲ and Ⅳ fed the basal diets supplemented with 0, 200, 500 and 1 000 g/t of 'QiYouNeng', respectively. On the first day after the end of the experiment, blood samples were collected from anterior venae cavae. Real-time fluorescence quantitative RT-PCR assay was used to determine the serum nucleic acid loads of PRRSV, and ELISA assay was employed to measure the serum levels of immunoglobulins （IgG, IgA and IgM） and cytokines （IL-2, TNF-α and IFN-γ）. Three piglets were chosen from each group and were dissected. Tissue samples of lungs, pulmonary hilar lymph nodes and spleens were collected and embedded in paraffin sections. Pathohistological changes were observed using HE staining, Masson's trichrome staining and immunofluorescence double-labeling staining. [Result] Compared with group Ⅰ, the serum PRRSV copy number in groups Ⅱ, Ⅲ and Ⅳ was extremely significantly （P<0.01） lower, the serum levels of IL-2 and IFN-γ in groups Ⅲ and Ⅳ were extremely significantly （P<0.01） higher, the serum levels of IgG in groups Ⅱ, Ⅲ and Ⅳ were extremely significantly （P<0.01） elevated, and the serum levels of IgA in groups Ⅲ and Ⅳ were significantly （P<0.05） and extremely significantly （P<0.01） increased, respectively. Pathohistological analysis demonstrated that in comparison to group Ⅰ, the damages of lungs, pulmonary hilar lymph nodes and spleens in groups Ⅲ and Ⅳ were obviously alleviated; significantly （P<0.05） as well as extremely significantly （P<0.01） elevated ratios of CD68 positive macrophages in lung tissues were observed in group Ⅱ as well as groups Ⅲ and Ⅳ, respectively; groups Ⅲ and Ⅳ had extremely significantly （P<0.01） higher ratios of CD163 positive macrophages in lung tissues and CD163/CD68. [Conclusion] Dietary supplementation of 'QiYouNeng' in the PRRSV-infected piglets exhibited the effects of reducing serum PRRSV load, enhancing immune function, and alleviating pathological damages of lung, spleen and pulmonary hilar lymph nodes, and the most obvious effect was achieved at the level of 1 000 g/t.

Bovine coronavirus （BCoV） is an important causative agent of diarrhea and respiratory infection in calves as well as winter diarrhea in adult cattle, which is prevalent in many countries and territories around the world, bringing huge economic loss to cattle farming. Currently, the available vaccines and drugs against BCoV infection is very limited. Accordingly, it is of great significance to research and develop the rapid detection methods for the early warning and effective control of BCoV infection. This paper reviewed the basic principles, application status as well as advantages and disadvantages of the main detection methods for BCoV, in hoping to provide references for the development and application of novel BCoV detection methods and the improvement of BCoV infection control.

Long-acting preparations are medications with long-lasting therapeutic effects, which have the advantages of decreased administration frequencies, reduced dosages and less harmful side effects. Long-acting preparations of traditional Chinese medicine that can continuously release drugs are developed on the basis of conventional traditional Chinese medicine pharmaceutical technology by combining with the carrier materials through unique preparation procedures. This paper reviewed the research progress on long-acting preparations of traditional Chinese medicine and the application in exterminating ectoparasite, in hoping to provide references for future research and clinical application of anti-ectoparasitic long-acting preparations of traditional Chinese medicine.

[Objective] This study was conducted to characterize the prevalence and species distribution of Cryptosporidium in dairy cattle on a large-scale introduction farm in Kashgar Prefecture, Xinjiang Uygur Autonomous Region. [Method] A total of 190 fecal samples were collected from dairy cattle of different age groups in this farm. Targeting on the small subunit ribosomal RNA gene （SSU rDNA）, PCR assay combined with sequencing were used to detect the Cryptosporidium infection. The species of Cryptosporidium were identified through SSU rDNA sequence alignment. Chi-square （χ²） test was performed to compare the differences in the Cryptosporidium infection rates among dairy cattle of different age groups. The gp60 genes of C. parvum, C. bovis and C. ryanae were amplified by PCR assay, and the subtypes of the 3 Cryptosporidium species were identified by sequence alignment. In addition, phylogenetic trees were constructed to analyze their genetic evolutionary characteristics. [Result] Thirty-two fecal samples of dairy cattle were positive for Cryptosporidium, with an overall infection rate of 16.84% （32/190）. Four Cryptosporidium species, including C. parvum （n=8）, C. andersoni （n=10）, C. bovis （n=10） and C. ryanae （n=4）, were identified. A higher infection rate of Cryptosporidium was observed in the pre-weaned calves under 3 months of age at 28.00% （14/50）. There were significant （χ²=8.679, P<0.05） differences in the infection rates of Cryptosporidium among dairy cattle of different age groups. Seven gp60 subtype sequences were obtained from the 8 C. parvum positive samples, with 2 subtypes identified as ⅡdA15G1 （n=3） and ⅡdA19G1 （n=4）. Six gp60 gene subtype sequences were obtained from the 10 C. bovis positive samples, with 3 subtypes identified as ⅩⅩⅥb （n=2）, ⅩⅩⅥc （n=3） and ⅩⅩⅥe （n=1）. The 4 C. ryanae positive samples were successfully subtyped with gp60 gene, all of which were identified as subtype ⅩⅪb. The phylogenetic tree analysis showed that the obtained Ⅱd subtype sequences of C. parvum in this study were in the same subgroup as the sequences of Ⅱd subtype family of C. parvum derived from different hosts, and were in different subgroups with the sequences ofⅡa subtype family of C. parvum derived from different hosts in New Zealand. Both the obtained subtype sequences of C. bovis and C. ryanae in this study were in the same group as those of cattle derived C. bovis and C. ryanae from different regions of China. [Conclusion] The Cryptosporidium prevalent in this introduction farm was characterized by diverse genetic distribution. The Cryptosporidium infection in dairy cattle occurred after being introduced locally, suggesting that water and forage pollution may be the primary causes of Cryptosporidium infection.

[Objective] By studying the physiological properties and bacteriostatic activities of bovine-derived lactic acid bacteria, it was possible to screen lactic acid bacteria that can have bacteriostatic effects on Pasteurella multocida （Pm） and Mannheimia haemolytica （Mh）, the main pathogens that lead to respiratory diseases in cattle. [Method] Growth curves of Lactobacillus rhamnosus （Lr）, Lactobacillus plantarum （Lp） and Lactobacillus acidophilus （La） isolated from healthy cattle faeces were performed. Meanwhile, the bacteriostatic activities of the three Lactobacillus strains were evaluated by detecting their susceptibility to antimicrobial drugs in the presence of proteases, at different pH values, and in co-culture with Pm and Mh. [Result] All three strains of Lactobacillus entered the logarithmic growth phase after 6 h of incubation, with Lr and Lp growing faster. They entered the stable growth period after 20 h of incubation, and the viable counts of Lr and Lp were always higher than those of La throughout the growth process. In addition, all three Lactobacillus strains were resistant to levofloxacin, moderately sensitive to kanamycin and streptomycin, and sensitive to ampicillin and erythromycin. Compared to the control, the culture supernatant of Lr showed a small decrease in the inhibitory activity against Pm and Mh after reaction with trypsin, pepsin and proteinase K. The culture supernatant of Lp showed no reduction in the inhibitory activity against Pm and Mh after reaction with pepsin and no change in the inhibitory activity against Mh after reaction with trypsin. There was no decrease in the inhibitory activity against Pm after reaction of culture supernatant of La with trypsin, pepsin and proteinase K. There was no change in the inhibitory activity against Mh after reaction with proteinase K. When the pH was 2-3, the inhibitory activities of culture supernatants of Lr and Lp were stronger on Pm than the control, and the inhibitory activities of culture supernatants of La were stronger on Mh than the control. When the pH was 4, the inhibitory activity of culture supernatants of all three strains of Lactobacillus was weaker than that of the control against Mh. When the pH was 5-6, the inhibitory activities of culture supernatants of the three Lactobacillus strains were weaker than those of the control group for both Pm and Mh, as well as weaker than those of the other pH groups. The growth of Pm and Mh was inhibited by the culture supernatants of the three Lactobacillus strains during the co-cultivation period from 0 to 60 h. The growth inhibition of Pm by the culture supernatant of Lr was consistently better than that of Lp and La. The growth inhibition of Mh by the culture supernatant of La was the most effective. [Conclusion] Bovine-derived Lr, Lp and La were sensitive or moderately sensitive to a variety of antimicrobial drugs, and had growth inhibitory abilities against Pm and Mh, the main pathogens of BRD. The inhibitory activities were enhanced at low pH and were not affected by the action of specific species of proteases. The three strains of Lactobacillus have the potential to be developed as microecological agents for the prevention and treatment of BRD.

Stevia rebaudiana possesses anti-oxidant, anti-bacterial, anti-cancer, anti-aging and lipid-lowering activities, and its leaves are important raw materials for producing sweeteners. Stevia rebaudiana by-products are the parts of Stevia rebaudiana that have been defoliated and processed, which are mainly composed of straws and residues. They have a considerable yield and are rich in active substances such as glycosides, flavonoids and chlorogenic acids. In addition, they exhibit various biological functions including anti-inflammation, anti-hyperglycemia and bacteriostasis, and have the potential to be used as animal feed. This paper summarized the nutritional composition and main bioactive substances of Stevia rebaudiana by-products, and reviewed the research progress on their application in animal production, in hoping to provide references for improving their feed utilization.

[Objective] The aims of the present study were to isolate and identify the Staphylococcus aureus （S. aureus） strain from fecal samples of lambs with diarrhoea, and to characterize the antimicrobial resistance and pathogenicity of the isolate. [Method] Four anal swab samples of diarrheic lambs were collected from a sheep farm in Emin County, Tacheng Prefecture, Xinjiang Uygur Autonomous Region, and S. aureus strain was selectively isolated with mannitol salt agar （MSA）. The isolate was identified by morphological observation and 16S rDNA sequence analysis. The in vitro susceptibility of the isolate to 11 antimicrobial agents belonging to 9 categories was analyzed by paper diffusion method. The presence of virulence genes of the isolate was detected by PCR assay. A model of abdominal infection in Kunming mice was established to evaluate the pathogenicity of the isolate. [Result] One suspected S. aureus strain was isolated from the four fecal samples of diarrheic lambs. It formed glossy, moderately raised, golden or lemon coloured colonies on MSA. Gram staining and morphological observation revealed that the isolate was Gram-positive and arranged in the form of grape bunches. The 16S rDNA sequence of the isolate was 100% similar to that of a S. aureus isolate of porcineluny origin from Changsha City, Hunan Province, China. Morphological observation and 16S rDNA sequence analysis confirmed that the isolate was S. aureus. The isolate was resistant to penicillin, clindamycin, cefotiamine, rifampicin and erythromycin, and was sensitive to gentamicin, azithromycin, chloramphenicol, norfloxacin, cefoxitin and cotrimoxazole. Out of the 20 virulence genes belonging to 8 classes tested, the presence of sea, seg, sei, eta, clfA and clfB genes was observed. The LD₅₀ of the isolate for Kunming mice was 2.24×10⁸ CFU/mL, with observable pathological changes in the organs of the dead mice. [Conclusion] One S. aureus strain was isolated and identified from the fecal samples of diarrheic lambs in a sheep farm in Emin County, which exhibited a multi-drug resistant phenotype, harbored multiple virulence genes and had certain pathogenicity. The results of this study provide references for the rational use of medication for the diseases caused by S. aureus infection in sheep in this region.

[Objective] The aim of the present study was to characterize the prevalence and the subgenotype distribution of Blastocystis in yaks in Gonghe County, Qinghai Province. [Method] A total of 475 fresh fecal samples were collected from yaks raised in Sangde pasture （n=89）, Kanzhuoxiangmao pasture （n=12） and Zanla family pasture （n=374） in Gonghe County. All of the samples were subjected to fecal genomic DNA extraction. Nested PCR assay was performed to detect the presence of SSU rDNA of Blastocystis, and selected positive PCR products were subjected to bidirectional sequencing. The subgenotype identification of Blastocystis was conducted based on the sequence alignment of SSU rDNA, and the phylogenetic tree was constructed to assess the genetic evolutionary relationships. [Result] Among the 475 yak fresh fecal samples, 361 samples were positive for Blastocystis, with a total infection rate of 76.00% （361/475）. The Blastocystis positive samples were observed in Sangde pasture, Kanzhuoxiangmao pasture and Zanla family pasture, and the infection rates of the three pastures were 96.63% （86/89）, 91.67% （11/12） and 70.59% （264/374）, respectively. A total of 126 SSU rDNA fragments were sequenced and used to perform subgenotype identification of Blastocystis. The sequence alignment analysis demonstrated that there were 5 subgenotypes of Blastocystis. The highest detection rate was observed in ST10 subgenotype （80.95%, 102/126）, followed by ST26 （9.52%, 12/126）, ST25 （6.35%, 8/126）, ST21 （2.38%, 3/126） and ST5 （0.80%, 1/126） subgenotypes. [Conclusion] Blastocystis infection in yaks was common in Gonghe County, and the subgenotypes exhibited genetic diversity. A zoonotic subgenotype of ST5 was observed, indicating that the infection monitoring of Blastocystis in yaks in this region was expected to be enhanced.

[Objective] This study was conducted to evaluate the production performance of three new cultivars of alfalfa （Medicago sativa L.） in Xinjiang Uygur Autonomous Region. [Method] The three new cultivars of alfalfa bred by Grass Germplasm Resources and Breeding Team in Xinjiang Agricultural University, designated as MX01, MX02 and MX03, were used as the research objects, and Xinmu No.4, an indigenously bred alfalfa cultivar in Xinjiang Uygur Autonomous Region was served as control （CK）. The plant height, dry to fresh ratio, leaf to stem ratio, fresh yield per harvest, total fresh yield, hay yield per harvest and total hay yield of the four tested alfalfa materials in three consecutive harvests within the same year were assessed and statistically compared. In addition, correlation analyses were performed between the associated trait indicators and total fresh yield or total hay yield. [Result] The average plant height of the four tested alfalfa materials in the three observed harvests from high to low were MX01 （95.23 cm）, CK （94.56 cm）, MX03 （90.25 cm） and MX02 （88.36 cm）, indicating that MX01 had a better performance in growth. The average dry to fresh ratio from high to low were MX02 （32.22%）, CK （28.81%）, MX01 （27.76%） and MX03 （25.36%）, revealing that MX02 had a better performance in dry matter accumulation. The average leaf to stem ratio from high to low were MX03 （70.85%）, MX02 （67.53%）, CK （66.68%） and MX01 （62.76%）, demonstrating that MX03 had a better performance in quality. The contribution rate of the fresh yield in the first two harvests to the total fresh yield of MX02 and MX03 was relatively higher, both reaching over 80%. The total fresh yield of the four tested alfalfa materials from high to low were MX03 （89.01 t/hm²）, MX02 （86.33 t/hm²）, CK （83.53 t/hm²） and MX01 （76.62 t/hm²）, with MX03 significantly （P<0.05） higher than the other materials, indicating that it was suitable for fresh grass production. There were evident differences in the contribution rate of the hay yield in the three separate harvest to the total hay yield among the three new cultivars. The total hay yield from high to low were MX02 （27.82 t/hm²）, CK （24.06 t/hm²）, MX03 （22.57 t/hm²） and MX01 （21.27 t/hm²）, demonstrating that MX02 was suitable for hay production. The fresh yield in the second harvest was extremely significantly （P<0.01） positively correlated with the total fresh yield, while the leaf to stem ratio in the second harvest was extremely significantly （P<0.01） negatively correlated with the total hay yield. [Conclusion] The evaluation results of multiple trait indicators of the three new cultivars of alfalfa in different harvests and the entire production cycle demonstrated that the comprehensive performance of MX02 and MX03 was better, and they had the potential to be promoted and planted in Xinjiang Uygur Autonomous Region.

[Objective] This study was conducted to investigate and analyze the competitiveness status of the indigenous pig farming enterprises in Yunnan Province and to provide references for enhancing their competitiveness. [Method] Based on the Michael Porter′s value chain theory and combined with the industry characteristics of indigenous pig farming enterprises and the availability of related data, a competitiveness evaluation index system composed of 20 indicators for the indigenous pig farming enterprises in Yunnan Province was established from the dimensions of enterprise capital, human resource, production status as well as science and technology level. The survey data were collected from 15 indigenous pig farming enterprises in 9 prefectures or cities of Yunnan Province in 2020, and were used to evaluate the competitiveness of the surveyed enterprises by using entropy weight TOPSIS method. [Result]①The competitiveness comprehensive level of the indigenous pig farming enterprises in Yunnan Province ranged from 0.102 4 to 0.634 0, with an average value of 0.368 7 and a standard deviation of 0.149 8. The highest value （0.634 0） was observed in the No.7 enterprise, which reached a good level. While the lowest one （0.102 4） was observed in the No.12 enterprise, which was at a poor level. ②In terms of each sub-item weight and level, enterprise capital had the highest （37%） weight, followed by production status （24%） as well as science and technology level （24%）, and human resource had the lowest （15%） weight. The average value, standard deviation and variation coefficient of enterprise capital level were 0.346 3, 0.184 2 and 0.531 9, respectively. The average value, standard deviation and variation coefficient of human resource level were 0.377 7, 0.183 7 and 0.486 4, respectively. The average value, standard deviation and variation coefficient of production status level were 0.378 2, 0.141 8 and 0.374 9, respectively. The average value, standard deviation and variation coefficient of science and technology level were 0.340 7, 0.221 6 and 0.650 4, respectively. [Conclusion] The competitiveness of the indigenous pig farming enterprises in Yunnan Province was relatively weak, and no enterprises reached the high-quality level. Only one enterprise reached the good level, and the vast majority of the enterprises were at the medium or below level. The human resource and production status of the surveyed enterprises were relatively good and exhibited minor gaps with each other. While the highly weighted enterprise capital as well as science and technology level were relatively weak and displayed disparities with each other. For enhancing the competitiveness of the indigenous pig farming enterprises in Yunnan Province, this paper suggests that the conservation and development of the excellent breeds of indigenous pig should be taken as the core, the development of leading enterprises should be fully supported, the own commercial brands should be established, and the scientific and technological innovation in pig farming should be emphasized.

[Objective] The aims of the present study were to characterize the prevalence and antimicrobial resistance pattern of Salmonella strains in pigeon flock of a pigeon breeding farm in Guangxi Zhuang Autonomous Region, and to provide references for the prevention and treatment of pigeon salmonellosis in this area. [Method] The clinical samples of liver were collected from the diseased or dead pigeons with suspected Salmonella infection in a pigeon breeding farm in Nanning City, Guangxi Zhuang Autonomous Region, and were subjected to isolation and culture of Salmonella strains. Phenotypic identification of the isolates was performed by Gram staining and microscopy, biochemical identification and serotype identification. Subsequently, the isolates were molecularly confirmed by PCR assay targeting invA gene specific for Salmonella. The antimicrobial susceptibility test of the isolates was conducted by Kirby-Bauer disk diffusion method. [Result] Two strains of Salmonella typhimurium, designated as S1 and S2, were isolated and identified from the clinical samples according to colony growth features, Gram staining characteristics, bacterial morphology, serotype identification, biochemical identification and molecular comfirmation. Both isolates were resistant to amoxicillin, streptomycin, lincomycin and nalidixic acid, moderately sensitive to erythromycin, cefthiophene and rifampicin, and sensitive to ciprofloxacin, cotrimoxazole, chloramphenicol and trimethoprim. [Conclusion] Two strains of Salmonella typhimurium were obtained from the clinical samples of the diseased or dead pigeons in a pigeon breeding farm in Nanning City, and the isolates exhibited high level resistance to certain antimicrobial agents, posing a potential threat to the health of breeding pigeon flocks in this area. It was recommended that detecting the prevalence of antimicrobial resistant Salmonella should be strengthened.

[Objective] This study was conducted to assess the effects of dietary supplementation of honeybee peptide on growth performance, diarrhea rate and economic benefits of weaned piglets. [Method] A total of eighty 21-day-old crossbred （Duroc×Landrace×Yorkshire） weaned piglets with similar body weights were randomly allocated into four dietary treatment groups, including a control group and three experimental groups （Ⅰ-Ⅲ）. There were two replicates in each group and ten piglets in each replicate. The piglets in control group fed a basal diet, and those in experimental groups Ⅰ-Ⅲ fed the same basal diets supplemented with 200, 400 and 600 mg/kg of a commercially available honeybee peptide, respectively. The feeding experiment consisted of a 7-day preparatory trial and a 28-day formal trail. The piglets were weighed at the beginning and at the end of the experiment. The feed intake and the number of piglets with diarrhea during the experiment were recorded. Subsequently, the average daily weight gain, average daily feed intake and diarrhea rate were calculated. In addition, the economic benefits were estimated according to the diet cost and weight gain of the piglets. [Result] Compared with the control group, the experimental groups Ⅰ-Ⅲ had significantly （P<0.05） elevated final weights, average daily weight gain and average daily feed intake, and had significantly （P<0.05） reduced feed to gain ratio and diarrhea rate. Compared with the experimental group Ⅰ, the experimental groups Ⅱ and Ⅲ had significantly （P<0.05） higher final weights, average daily weight gain and average daily feed intake, and had significantly （P<0.05） lower feed to gain ratio and diarrhea rate. The experimental group Ⅲ had superior final weights, average daily weight gain, average daily feed intake, feed to gain ratio and diarrhea rate to experimental group Ⅱ, while no significant （P>0.05） differences were observed. The individual profits of the experimental groups Ⅰ-Ⅲ were 11.926, 23.986 and 27.224 Yuan higher than the control group, respectively, and the best economic benefit was observed in experimental group Ⅲ. [Conclusion] Dietary supplementation of honeybee peptide has significant effects on improving growth performance, reducing diarrhea rate, and increasing economic benefit of the weaned piglets. The addition level of 600 mg/kg is recommended.