[Objective] The P113 genes of Mycoplasma ovipneumoniae isolates from Inner Mongolia were cloned, and the P113 protein sequences of various isolates were bioinformatically compared and analyzed, so as to provide references for clarifying the biological function of Mycoplasma ovipneumoniae P113 protein. [Method] A set of specific primers were designed to amplify the P113 gene fragments of 9 isolates of Mycoplasma ovipneumoniae from Inner Mongolia. The obtained P113 gene fragments of various isolates were sequenced. The DNA sequences were then translated into amino acid sequences, and the differences in amino acid sequences among various isolates were bioinformatically compared. [Result] The PCR amplified products of P113 gene of various isolates varied in size. According to amino acid sequence analysis, the lengths of C-terminal repetitive elements were variable. KKAEGA (S) QNQG was the dominantly observed repetitive element. The number of repetitive elements of the isolates varied. The most repetitive elements were found in the NM01-MO isolate and CK-MO isolate, both of which were 16. The least repetitive elements were found in the LK-MO isolate, which were 3. Most isolates had large differences in the number of repetitive elements. [Conclusion] The number of C-terminal repetitive elements in the amino acid sequence of P113 protein of Mycoplasma ovipneumoniae isolates from Inner Mongolia was variable. These repetitive elements had an impact on P113 protein structure, which could then have an impact on its biological activity.

The incidence of mastitis, ketosis, fatty liver and some other diseases in dairy cow farming has increased year after year as large-scale and intensive dairy cow farming improved. As an energy receptor, AMP-activated protein kinase （AMPK） reflects the energy state of cells. AMPK plays crucial roles in glucose, lipid and protein metabolism as well as in mitochondrial biogenesis and autophagy. AMPK is thought to be a potential intervention or treatment target for a variety of diseases and has been extensively studied in metabolic diseases of dairy cows. This paper reviews the research progress on regulative roles of AMPK in dairy cow mastitis, ketosis and fatty liver, in hoping to provide references for targeted treatment of these diseases.

[Objective] This study was conducted to assess the effects of compound lactic acid bacteria preparation on growth performance, intestinal microflora, anti-oxidation capacity and immunity of calves. [Method] A total of twenty 30-day-old healthy Holstein calves of similar weights were randomly divided into a control group and an experimental group with 10 individuals for each group. The two groups were fed with the same basal diet. The experimental group received an supplementation of compound lactic acid bacteria preparation through drinking water （the ratio of drinking water to compound lactic acid bacteria preparation was 50∶1）, whereas the control group received no microbial preparation in any forms. The experiment lasted for 90 days. The average daily gain and diarrhea rate of the calves in the two groups during the experiment were calculated. On days 1, 30, 60 and 90 of the experiment, the total number of bacteria as well as the number of lactic acid bacteria and Escherichia coli in the faecal samples, and the blood biochemical, antioxidant and immunological indexes were determined. [Result] No significant （P>0.05） difference in average daily gain between the experimental group and the control group was observed. The experimental group had a lower diarrhea rate than control group. The number of lactic acid bacteria in feces of the calves in the experimental group reached 1.41×10⁷ CFU/g, which was significantly （P<0.05） higher than that of the calves in the control group, while the number of Escherichia coli in feces was significantly （P<0.05） lower than the control group. On days 30 and 90 of the experiment, the experimental group had significantly （P<0.05） higher serum content of glucose （GLU） in comparison to the control group. On days 60 and 90 of the experiment, the experimental group had significantly （P<0.05） lower serum content of total protein （TP） than the control group. The anti-oxidant indexes did not differ significantly （P>0.05） between the two groups. Calves in the experiment group had higher serum levels of IgG and IgA on day 90 of the experiment compared with the control group. [Conclusion] The addition of compound lactic acid bacteria preparation in drinking water improved the community structure of intestinal microflora and decreased the diarrhea rate of Holstein calves.

[Objective] This experiment was conducted to explore the effects of different initial water contents and co-fermentation with probiotics and protease on quality of soybean meal. [Method] ① A single factor experimental design was adopted to determine the optimal ratio of fermentation material to initial water. Five treatment groups with different initial water contents were set up, and the ratios of material to water were 1∶0.4, 1∶0.5, 1∶0.6, 1∶0.7 and 1∶0.8, respectively. There were three replicates for each treatment group. The compound probiotics （Bacillus subtilis∶yeast∶Enterococcus faecalis=1∶1∶1） were used as starter to ferment soybean meal, and the apparent characteristics, nutritional indicators and living bacteria contents of the fermented soybean meal were assessed. ②A single factor experimental design was used to set up five treatment groups with different neutral protease addition amount of 0, 100, 200, 400 and 800 IU/g. Each treatment group had three replicates. The apparent characteristics, nutritional indicators, live bacteria contents, and protein subunit distribution of the fermented soybean meal were further analyzed to determine the optimal neutral protease addition amount. [Result] ①There was no significant （P=0.074） difference in crude protein level of the fermented soybean meal with varied ratios of material to water. The highest crude protein level of the fermentation product was observed when the ratio of material to water was 1∶0.6, which was elevated by 9.39% compared with the soybean meal before fermentation. With the increase of initial water content of the fermentation system, the pH value of fermented soybean meal was decreased significantly （P<0.01）, while the content of lactic acid and the survival amount of the three species of microbes in the compound probiotics were elevated significantly （P<0.01）. The content of lactic acid after fermentation in 1∶0.6 treatment group was significantly （P<0.05） higher than that in 1∶0.4 and 1∶0.5 treatment groups. The survival amount of the three species of microbes in the compound probiotics was the highest when the ratio of material to water was 1∶0.8, with the total amount reached 1.43×10⁹ CFU/g. Considering the industrial production conditions with the above results, the optimal ratio of material to water for the subsequent experiment was determined as 1∶0.6.②With the ratio of material to water at 1∶0.6, different protease addition levels had no significant （P>0.05） effect on the crude protein content of fermented soybean meal. However with the increase of protease addition amount, the proportion of small molecular proteins in fermentation product increased linearly. In the treatment group with protease addition of 800 IU/g, the proportion of proteins with molecular weights less than 30 kDa was as high as 65.56%, which was 2.61 times higher than that in the group without protease addition. The survival amount of the three species of microbes in the compound probiotics was decreased with the increase of protease addition amount. The survival amount of Bacillus subtilis and Enterococcus faecalis in 100 IU/g treatment group was extremely significantly （P<0.01） higher than that in 200, 400 and 800 IU/g treatment groups, and that of yeast was extremely significantly （P<0.01） higher in comparison to 400 and 800 IU/g treatment groups. [Conclusion] The quality of soybean meal can be effectively improved by a co-fermentation with addition of compound probiotics and 100 IU/g neutral protease in the substrates at a ratio of material to water of 1∶0.6.

[Objective] This study was conducted to investigate the synergistic effects of feeding bacteria and enzymes on growth performance, serum immune indexes and intestinal microflora of weaned piglets of Licha black pig. [Method] A total of 80 healthy 28-day-old weaned piglets of Licha black pig with body weights of （6.72±0.12） kg were randomly divided into the following four groups: a control group fed with basal diet, a probiotic group fed with basal diet supplemented with 1‰ of probiotic, an enzyme preparation group fed with basal diet supplemented with 1‰ enzyme preparation, and a bacteria and enzymes synergistic group fed with basal diet supplemented with 1‰ probiotic and 1‰ enzyme preparation. The experiment lasted for 35 d, including a 7 d pre-feeding period and a 28 d formal feeding period. The average daily gain, average daily feed intake, ratio of feed to weight gain and diarrhea index were calculated, and the serum levels of IgM and IgG were determined. The composition and relative abundance of intestinal micoflora were examined by 16S rDNA high-throughput sequencing. [Result] Compared with the control group, the average daily feed intake of the probiotic group, enzyme preparation group, and bacteria and enzymes synergistic group increased significantly （P<0.05）; the enzyme preparation group and bacteria and enzymes synergistic group had significantly （P<0.05） increased average daily gain and significantly （P<0.05） decreased ratio of feed to weight gain; the diarrhea index of probiotic group and bacteria and enzymes synergistic group extremely significantly （P<0.01） reduced. The probiotic group, enzyme preparation group, and bacteria and enzymes synergistic group had significantly （P<0.05） higher serum levels of IgM and IgG than control group. Significantly （P<0.05） higher Chao1 index of intestinal microflora was observed in probiotic group, enzyme preparation group, and bacteria and enzymes synergistic group compared with control group. At the phylum level, the relative abundance of Bacteroides in probiotic group as well as bacteria and enzymes synergistic group was significantly （P<0.05） higher than that in control group. [Conclusion] The bacteria and enzymes synergistic feeding mode increased the average daily feed intake and average daily gain, reduced the diarrhea index, enhanced the body immunity, and improved the intestinal microbial community structure of weaned piglets of Licha black pig.

[Objective] This study was conducted to assess the effects of different dosages of total flavonoids from wild apricot （TFWA） on slaughter performance of Sanhuang broiler chickens. [Method] Using a single factor experimental design, a total of 96 1-day-old female Sanhuang broiler chickens were randomly assigned into 4 groups with 24 broilers in each group. Science the 14 days of age, broiler chickens in the low, medium and high dosage groups were administrated with 50, 100 and 200 mg/（kg·BW·d） of TFWA by oral gavage, respectively, while those in the control group were given physiological saline. The experiment lasted for 42 days. At the 28, 35 and 42 days of age, 8 broiler chickens from each group were chosen and slaughtered, respectively, and the indexes associated with slaughter performance of the broilers with the same days of age among different groups were determined and statistically compared. [Result] High dosage of TFWA significantly or extremely significantly （P<0.05 or P<0.01） increased the pre-slaughter weights of broiler chickens aged 28, 35 and 42 days, and medium dosage of TFWA extremely significantly （P<0.01） increased the pre-slaughter weights of 35-day-old broiler chickens. High dosage of TFWA significantly （P<0.05） and extremely significantly （P<0.01） improved the slaughter rate of broiler chickens aged 35 and 42 days, respectively. Medium and high dosages of TFWA extremely significantly （P<0.01） elevated the percentage of eviscerated yield with giblet of 28-day-old broiler chickens. Low dosage of TFWA extremely significantly （P<0.01） and significantly （P<0.05） increased the percentage of eviscerated yield of broiler chickens aged 28 and 35 days, respectively. Medium dosage of TFWA extremely significantly （P<0.01） boosted the percentage of eviscerated yield of 35-day-old broiler chickens. Low, medium and high dosages of TFWA extremely significantly （P<0.01） increased the percentage of eviscerated yield of 42-day-old broiler chickens. Low, medium and high dosages of TFWA significantly or extremely significantly （P<0.05 or P<0.01） reduced the subcutaneous fat thickness of broiler chickens aged 35 and 42 days. High dosage of TFWA significantly （P<0.05） and extremely significantly （P<0.01） decreased the intermuscular fat width of broiler chickens aged 28 and 35 days, respectively. Low, medium and high dosages of TFWA extremely significantly （P<0.01） reduced the intermuscular fat width of 42-day-old broiler chickens. Low dosage of TFWA significantly （P<0.05） decreased the abdominal fat rate of broiler chickens aged 28 and 42 days. Medium dosage of TFWA significantly （P<0.05) reduced the abdominal fat rate of broiler chickens aged 28, 35 and 42 days. High dosage of TFWA extremely significantly （P<0.01） decreased the abdominal fat rate of 42-day-old broiler chickens. High dosage of TFWA significantly or extremely significantly （P<0.05 or P<0.01） elevated the percentage of breast meat of broiler chickens aged 35 and 42 days, and significantly or extremely significantly （P<0.05 or P<0.01） increased the percentage of leg meat of broiler chickens aged 28, 35 and 42 days. [Conclusion] Oral gavage of different dosages of TFWA was capable of improving the slaughter performance of Sanhuang broiler chickens.

[Objective] The present study aimed to evaluate the controlled-releasing performance of benzoic acid in different forms in vitro and in vivo. [Method] This study consisted of two parts, an in vitro dissolution test and an in vivo controlled-release test. ① In vitro dissolution test: Artificial gastric liquid and artificial intestinal liquid was prepared, with ordinary benzoic acid or controlled-release benzoic acid in the 200 mesh baskets. Samples were taken from the dissolution meter at 1, 2 h for artificial gastric liquid or 1, 2, 3 and 4 h for artificial intestinal liquid. High-performance liquid chromatography （HPLC） was used to determine the content of benzoic acid, and the dissolution rate and retention rate were calculated. ② In vivo controlled-release test: A total of 36 healthy Qingyuanma broilers with similar weights were selected and assigned into 3 groups after pre-feeding, with 12 individuals in each group. After morning feeding, the broilers in control group, ordinary benzoic acid group and controlled-release benzoic acid group were immediately fed with pure flour pills, flour pills containing 0.1% ordinary benzoic acid and flour pills containing 0.1% controlled-release benzoic acid, respectively. On 0, 1, 2 and 4 h after given the pills, three broilers were chosen from each group, respectively. The broilers were slaughtered and the contents in each segment of gastrointestinal tracts were taken. The concentration of benzoic acid in the gastrointestinal contents of broilers were assessed by HPLC. [Result]① In vitro dissolution test: In artificial gastric liquid for 1 h, the retention rate of controlled-release benzoic acid was 3.45 times that of ordinary benzoic acid. In artificial gastric liquid for 2 h, ordinary benzoic acid was not detected, while the retention rate of controlled-release benzoic acid was 56.18%. The retention rate of controlled-release benzoic acid was 40.10% in the artificial intestinal fluid for 4 h, while ordinary benzoic acid was not detected at 1 h. ② In vivo controlled release test: The concentration of benzoic acid in glandular stomach and muscular stomach of the controlled-release benzoic acid group was 5.46 times of the ordinary benzoic acid group 1 h post ingestion of the pills, exhibiting a significant （P<0.05） difference. The concentration of benzoic acid in contents of jejunum, ileum and cecum of the controlled-release benzoic acid group 2 h post ingestion of the pills was 1.61, 2.43 and 1.95 times of the ordinary benzoic acid group, respectively, all exhibiting significant （P<0.05） differences. The concentration of benzoic acid in ileum contents of the controlled-release benzoic acid group was 6.68 times of the ordinary benzoic acid group 4 h post ingestion of the pills, exhibiting a significant （P<0.05） difference. [Conclusion] Both in vitro dissolution test and in vivo controlled-release test showed that the controlled-release benzoic acid prepared by coating treatment had a high gastric pass rate and was able to slowly release into the entire intestinal tract after entering to achieve long-term antibacterial effect.

Astragalus membranaceus contains a variety of bioactive substances including polysaccharides, saponins and flavonoids, and has the activities of enhancing immunity, anti-oxidation, anti-bacteria, anti-virus, anti-tumor, anti-aging, regulating blood pressure and preventing diabetes. The application of Astragalus membranaceus helps to boost the body′s immune system and anti-oxidation system of livestock and poultry, and improve the growth performance and product quality. The biological activities of Astragalus membranaceus and its application in livestock and poultry production were reviewed, in hoping to provide references for the research, development and application of Astragalus membranaceus products for animal use.

Pepper, serving as both condiment and vegetable, plays an important role in human daily diet and health. In addition, pepper and its extracts can boost livestock and poultry productivity by enhancing disease resistance, improving feed conversion ratio, and alleviating heat stress. This paper introduced three application modes of pepper （pepper powder, capsaicin, capsicum oleoresin） as feed additives, as well as its application and action mechanisms in poultry, pigs, ruminants, rabbits, rats and aquatic animals, in hoping to provide a fresh perspective on the use of pepper and its extracts in animal production.

Improving the quality, nutritional value, palatability and lowering the contents of phytic acid and thioglycoside of rapeseed meal feed through fermentation by bacteria coupled with enzymes, as well as increasing the proportion of rapeseed meal feed replacing conventional protein feedstuff help to alleviate the problem of rising costs of protein feed materials such as soybean meal in animal husbandry. In this paper, the benefits and drawbacks of the commonly used methods （microbial fermentation and enzymatic digestion） for preparing fermented rapeseed meal were analyzed, and the types of bacteria and enzymatic preparations used in fermentation of rapeseed meal feed by bacteria coupled with enzymes were introduced. In addition, the feeding value of fermented rapeseed meal by bacteria coupled with enzymes was reviewed, and its application status in animal production and existing problems were described, in hoping to provide a reference for the scientific application of fermented rapeseed meal by bacteria coupled with enzymes in livestock and poultry production.

[Objective] This study was conducted to analyze the correlation between body weight and body size indexes of Sunit sheep, a local distinctive mutton sheep breed in Xilin Gol League of Inner Mongolia, China. [Method] A total of 247 Sunit rams and a total of 260 Sunit ewes aged 5 to 6 months with good development and health condition were randomly selected, and the indexes potentially associated with production performance including body weight （Y）, tail length （X₁）, tail width （X₂）, body height （X₃）, body length （X₄） and chest circumference （X₅） were measured. Following data processing, SPSS 26.0 software was used to perform correlation analysis and multiple linear regression analysis on the body weight and body size indexes. The best regression model was then established. [Result] The main body size indexes affecting the body weights of Sunit rams and ewes were tail width, body height, body length and chest circumference, which were all extremely significantly （P<0.01） correlated with the body weight. A multiple linear regression model was established by stepwise regression analysis. The optimal linear equation of Sunit ram was: Y=0.57X₅+0.325X₄+0.241X₂-35.795, R²=0.834; the optimal linear equation of Sunit ewe was: Y=0.577X₅+0.246X₄+0.205X₂-31.94, R²=0.799. [Conclusion] The body size indexes of chest circumference, body length and tail width had high correlation with body weight in the regression equation, and all of them could be used as the prediction indicators for body weight.

[Objective] This study was conducted to assess the correlation between litter size and parity of Huanghuai goat. [Method] The lambing record data of a total of 71 female Huanghuai goats with parities ranging from 1 to 5 were statistically analyzed. The goats with average litter size per parity and maximum litter size per parity less than or equal to 2 were categorized in low yield group （n=37）, and those with average litter size per parity more than 2 were categorized in high yield group （n=34）. The correlation between litter size and parity was evaluated. [Result] The average litter size per parity of Huanghuai goats was 2.56, and that of high yield group and low yield group was 3.66 and 1.66, respectively. In general, the average litter size per parity of the entire female goat population and the high yield group increased initially before declining as parity increased, peaking between the third and fourth parity. The regression equations of litter size and parity for the entire female goat population and the high yield group were Y₁ = 0.753X-0.096X²+1.394 and Y₂= 1.497X-0.196X²+1.400, respectively. [Conclusion] The high yield group of female Huanghuai goats demonstrated good reproductive performance in the first or second parities. The change of litter size of the entire female goat population and the high yield group presented an inverted U shape with the increase of parity, while litter size of the low yield group was less affected by parity.

[Objective] The present study aimed to explore the growth and development characteristics as well as genetic traits of Xinggao mutton sheep. [Method] The data on birth weights, weaning weights as well as weights at 6 and 12 months of age of a total of 1 054 Xinggao lambs born between the year of 2018 and 2019 were statistically analyzed. Additionally, measurements of body height, body length and chest circumference of selected lambs were taken at 6, 12 and 24 months of age. Each lamb′s birth type and pedigree file were recorded in detail. WOMBAT software was used to undertake genetic evaluation on the birth weight and weaning weight. [Result] The heritability of birth weight and weaning weight of Xinggao lambs was 0.980 and 0.885, respectively, and the phenotypic and genetic correlations were 0.321 and 0.396, respectively. At 6 months of age, the weights of the ram lambs and ewe lambs represented 44.21% and 60.33% of those of their adult counterparts, respectively, and their body measurements exceeded 80% of those of the adults. [Conclusion] The birth weight and weaning weight of Xinggao mutton sheep were highly heritable and adhere to the genetic traits of rapid growth and development in the early stages of breeds for meat production.

[Objective] This study was conducted to investigate the differences and changing characteristics of nutrient contents of soil and vegetation in typical grasslands in Inner Mongolia at different periods, and to provide references for the rational utilization of typical grasslands, the restoration and management of degraded grasslands, and the sustainable development of animal husbandry in Inner Mongolia. [Method] A total of eight monitoring points were selected from the typical grasslands in different regions of Inner Mongolia, including G1 （Ewenki Grassland, temperate meadow grassland, Hulun Buir City）, G2 （Urad Grassland, desert grassland, Bayannur City）, G3 （natural grassland, Ulanqab City）, G4 （Huitengxile Grassland, tessellated meadow grassland, Ulanqab City）, G5 （Horqin Grassland, temperate meadow grassland, Tongliao City）, G6 （artificial forage planting site, Chifeng City）, G7 （Urad Grassland, desert grassland, Baotou City), and G8 （Gegentala Grassland, desert grassland, Ulanqab City）. In the year of 2020, the soil samples of 0-20 cm soil layers and the above-ground parts of plant samples were taken at different monitoring points during the re-greening, vigorous and withering periods of forage, respectively. The contents of the conventional nutrients in the soil and plant samples were determined. The comprehensive scores of soil and vegetation nutrient levels at different monitoring points at different periods were calculated and sorted by using the principal component analysis method. [Result] The content of soil total nitrogen （STN） in G4 monitoring point （Huitengxile Grassland) during the re-greening, vigorous and withering periods was the highest, which was extremely significantly （P<0.01） higher than that in the other monitoring points; while G7 monitoring point （Urad Grassland within the boundaries of Baotou City） had the lowest STN at both vigorous and withering periods. The highest content of soil available phosphorus （SAP） was seen over the three observed periods in G6 monitoring point （artificial forage planting site）, which was significantly （P<0.05） or extremely significantly （P<0.01） higher compared with the other monitoring points. Over the three observed periods, the content of soil organic matter （SOM） in G4 monitoring point （Huitengxile Grassland） was the highest, which was extremely significantly （P<0.01） higher than that in the other monitoring points; while G7 monitoring point （Urad Grassland within the boundaries of Baotou City） had the lowest SOM. At the re-greening period, the contents of plant nitrogen, phosphorus and potassium in G6 monitoring point （artificial forage planting site） were the highest, which were extremely significantly （P<0.01） higher than those in the other monitoring points. At the vigorous period, the highest contents of plant nitrogen and potassium were observed in G8 monitoring point （Gegentala Grassland）, while the highest content of plant phosphorus was found in G6 monitoring point （artificial forage planting site）. At the withering period, G3 monitoring point （natural grassland within the boundaries of Ulanqab City） had the highest contents of plant nitrogen and phosphorus, while G4 monitoring point （Huitengxile Grassland） had the highest content of plant potassium. Over the three observed periods, the highest and the lowest contents of plant crude fiber were found in G5 monitoring point （Horqin Grassland） and in G4 monitoring point （Huitengxile Grassland）, respectively. For the score of soil nutrient status over the three observed periods, G4 monitoring point (Huitengxile Grassland) had higher rankings, while G7 monitoring point （Urad Grassland within the boundaries of Baotou City） showed the worst performance. As for the score of plant nutrient status, both G2 monitoring point （Urad Grassland within the boundaries of Bayannur City） and G6 monitoring point （artificial forage planting site） had the highest rankings at the re-greening period, followed by the vigorous period and the withering period; while all the other monitoring points exhibited the best performance in the vigorous period, followed by the re-greening period and the withering period. [Conclusion] There were obvious seasonal and regional variations in nutrient contents of the soil and vegetation in typical grasslands in Inner Mongolia. On the whole, the meadow grassland had higher comprehensive scores regarding soil nutrient contents during the re-greening, vigorous and withering periods, while the desert grassland had lower comprehensive scores across the three observed periods. Furthermore, the comprehensive scores of vegetation nutrient of different grassland types were generally higher at the vigorous period and lower at the withering period.

[Objective] The aim of the present study was to explore the effects of storage years on seed vigour of Bothriochloa ischaemum of different populations. [Method] Bothriochloa ischaemum seeds of five populations （Daixian, Pinglu, Pingding, Liulin and Taigu） harvested in the years of 2017, 2018, 2019 and 2020 were used as materials for the germination tests, respectively. The changes in seed germination rate, germination index and average germination time, as well as seedling vigour index with the variations of storage years were characterized. The difference in storage durability of Bothriochloa ischaemum seeds of various populations were assessed. [Result] The seed germination rate and germination index as well as seedling vigour of Bothriochloa ischaemum were all extremely significantly （P<0.01） impacted by storage years, populations and their interactions. With the extension of storage years, the seed germination rate and germination index as well as seedling vigour index of Bothriochloa ischaemum of different populations showed a downtrend. For Taigu population, while there were no significant （P>0.05） differences in germination rate and germination index among the seeds currently harvested and stored for 1 and 2 years, significantly （P<0.05） decreased germination rate and germination index were observed in the seeds stored for 3 years; the seedling vigour index had no significant （P>0.05） changes as storage years increased. For the other populations, the seeds currently harvested had significantly （P<0.05） higher germination rate and germination index as well as seedling vigour index in comparison to those stored for 1, 2 and 3 years. In the year of harvest, the Liulin population had higher seed germination index and seedling vigour index as well as lower average germination time compared with the remaining populations, and showed a higher germination rate. Storage years extremely significantly （P<0.01） affected the average germination time of Bothriochloa ischaemum seeds, and the average germination time was prolonged with the increase of storage years. Populations also extremely significantly （P<0.01） influenced the average germination time of Bothriochloa ischaemum seeds. However, the interactions between storage years and populations had no significant （P>0.05） effects on the average germination time of Bothriochloa ischaemum seeds. [Conclusion] Different populations of Bothriochloa ischaemum seeds maintained a higher level of vigour in the harvest year, with Liulin population being the highest. The Taigu population exhibited the best storage durability, maintaining high levels of seed vigour within 3 years of storage. The other populations were unsuitable for storage over a long period.

[Objective] This study was conducted to clarify the adaptability of seed germination and seedling growth of Astragalus laxmannii to different salt stresses. [Method] Astragalus laxmannii seeds were exposed to five gradient concentrations of NaCl, Na₂SO₄, and Na₂CO₃ solutions respectively at 0 （CK）, 10, 20, 30, and 40 mmol/L. Three replicates were set for each treatment concentration of each salt solution. Under the treatments of different salt solutions, the germination rate, germination potential, germination index, vigour index, and relative salt damage rate of Astragalus laxmannii seeds were calculated, and the seedlings′ height and root length were measured. [Result] The indexes associated with seed germination and seedling growth of Astragalus laxmannii declined as salt solution concentrations increased. Compared with CK group, the germination rate, germination potential, germination index, and vigour index of Astragalus laxmannii seeds decreased significantly （P<0.05） when the concentration of NaCl, Na₂SO₄, and Na₂CO₃ solutions was 40 mmol/L, and the seedlings′ height and root length decreased significantly （P<0.05） as well. The Astragalus laxmannii seedlings′ root length in 10 mmol/L Na₂SO₄ solution treatment group was 5.5% longer than that in CK group, indicating the promoting effect of Na₂SO₄ solution on the seedlings′ root growth at low concentrations. Na₂CO₃ solution treatments resulted in severe salt damage to Astragalus laxmannii seeds. The indexes associated with seed germination and seedling growth of Astragalus laxmannii in Na₂CO₃ solution treatment groups were all significantly （P<0.05） lower than those in CK group, and the differences among varied treatment concentrations were large. [Conclusion] Astragalus laxmannii seeds were most tolerant to Na₂SO₄ salt stress, followed by NaCl and Na₂CO₃ salt stresses. While low concentrations of Na₂SO₄ solution had certain promoting effect on seed germination and seedling growth of Astragalus laxmannii, Na₂CO₃ solution had strong inhibitory effect.

[Objective] This study aimed to assess the developmental status in the filed of alfalfa silage research in China. [Method] The alfalfa silage associated literature indexed in CNKI database was selected as the research object, and the knowledge map of research literature on alfalfa silage was drawn by using the visual and metrological analysis software CiteSpace 5.8.R3. The cooperative network analysis was performed for the institutions and authors in the filed of alfalfa silage research, and the co-occurrence, clustering and emergence analyses were carried out for the keywords. [Result] Under the set retrieval conditions, the first research paper on alfalfa silage appeared in the year of 1994. The annual number of alfalfa silage publications showed an upward trend from the year of 1994 to 2021. Heilongjiang Animal Husbandry and Veterinary Medicine published the most research papers （31）. Acta Prataculturae Sinica had the highest total citation frequency （763 times） and citation frequency per paper （31.79 times）. Yuzhu, an author from China Agricultural University published the most papers （34）, and China Agricultural University was the organization with the most publications （57）. A stable scientific research team has been formed with Yuzhu as the focal point, but collaborations among varied institutions and teams were insufficient. The most frequently used keyword was alfalfa silage （103 times）. Researches were carried out focusing on the keywords such as fermentation quality, silage quality, mixed silage, additives and lactic acid bacteria. [Conclusion] The research achievements on alfalfa silage in China are rich, and more collaborations across institutions, regions and teams are necessary. Fermentation quality as well as composition and function of microbial community of alfalfa silage, and research and development of microbial preparations for alfalfa silage are still the developmental trends in the field of alfalfa silage research in China.

[Objective] This study was conducted to explore the quantitative indexes for classifying hazard grade of Stellera chamaejasme L. （S. chamaejasme）, and to provide references for regional poisonous weed control. [Method] Large sample plots were set up in the representative zones with mild, moderate and severe occurrences of S. chamaejasme population respectively to investigate the population characteristics of S. chamaejasme in grassland ecosystems under different hazard grades. Each large sample plot was 100 m×100 m with more than 10 km apart from each other. Four medium quadrats were randomly set up in large sample plot, with an area of 10 m×10 m for each quadrat and more than 10 m apart from each other. The small quadrats with an area of 2 m×2 m for each were randomly arranged in the medium quadrat for each investigation with 5 replicates. The quadrat survey included the height, coverage, density and above ground biomass of the vegetation community and S. chamaejasme population, as well as the individual cluster width and branch number of S. chamaejasme. Statistical analysis was performed to determined the population characteristics of S. chamaejasme in zones with different hazard grades and their relationship with the characteristics of the vegetation community. [Result] The coverage, height, density and above ground biomass of S. chamaejasme population as well as the individual branch number all increased as the hazard grades increased. In the mild, moderate and severe hazard grade zones, the population average coverage was 13.75%, 32.85% and 49.50%, respectively, with significant （P<0.05） differences. The population average height was 21.59 cm and 21.24 cm in the severe and moderate hazard grade zones, respectively, with no significant （P>0.05） difference. But both were significantly （P<0.05） higher than that in the mild hazard grade zone （19.29 cm）. The population average density was 1.95, 3.42 and 7.16 plants/m² in the mild, moderate and severe hazard grade zones, respectively, with significant （P<0.05） differences. The population average above ground biomass was 34.79, 70.73 and 98.39 g/m² in the mild, moderate and severe hazard grade zones, respectively, with significant （P<0.05） differences. The individual average branch number in the severe and moderate hazard grade zones was 34.59 and 32.25, respectively, with no significant （P>0.05） difference. But both were significantly （P<0.05） higher than that in mild hazard grade zone （13.73）. The individual average cluster width was 354.96, 698.95 and 607.10 cm²/plant in the mild, moderate and severe hazard grade zones, respectively, with significant （P<0.05） differences. [Conclusion] The coverage and density could be given priority in quantitative classification for hazard grade of S. chamaejasme in degraded grassland.

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

[Objective] The present study aimed to understand the situation of Cystoisospora suis infection in large-scale pig farms in partial areas of Xinjiang, China. [Method] Primers targeting the SSU rDNA gene locus of Cystoisospora suis were designed. A total of 801 DNA samples extracted from fresh pig feces collected from 7 large-scale pig farms in Xinjiang were screened for the presence of target gene by using nested PCR assay. Cystoisospora suis infection rates in pigs of various farms and ages were statistically assessed. The obtained SSU rDNA sequences were bioinformatically compared and analyzed, and a phylogenetic tree was constructed. [Result] The general infection rate of Cystoisospora suis in the surveyed pig farms was 5.74% （46/801）, and the highest infection rate （14.00%, 14/100） was observed in the pig farm in Shaya County. Cystoisospora suis infection rates among various pig farms were statistically significantly （χ²=27.081, df=6, P<0.01） different. In unweaned piglets, weaned piglets, fattening pigs and sows, the Cystoisospora suis infection rates were 14.79% （25/169）, 5.78% （13/225）, 2.31% （4/173） and 1.71% （4/234）, respectively. Cystoisospora suis infection rates in pigs of various ages were statistically significantly （χ²=36.366，df=3，P<0.01） different. In sequence comparison and phylogenetic analysis, the SSU rDNA sequences （n=46） of Cystoisospora suis obtained in this study had 100% homology with the SSU rDNA sequence of a Cystoisospora suis isolate from Fengyang County, Anhui Province （GenBank accession number: KX808495）, and they were genetically categorized in the same subgroup. [Conclusion] Infections caused by Cystoisospora suis were common in large-scale pig farms in partial areas of Xinjiang, so detection and prevention should be strengthened.