[Objective] This study was conducted to explore the ovum pick-up and in vitro fertilization （OPU/IVF） technology in cattle, and to establish a high-efficient in vitro embryo production system for cattle. [Method] The fresh ovaries of healthy cattle collected from slaughterhouses were used as experimental materials to perform oocyte maturation as well as fertilization and embryo culture under in vitro conditions, with focus on the effect of leptin supplementation in culture medium on blastocyst rate. Healthy Holstein dairy cows （n=10） and Wagyu cattle（n=10） aged 13 to 15 months were selected as donors, and ovum pick-up as well as oocyte maturation and embryo production under in vitro conditions were carried out. For both breeds, the number of available oocytes and blastocysts was recorded, and the cleavage rates and blastocyst rates were calculated. After thawing of the prepared frozen embryos of the donors, Holstein dairy cows were used as recipients for embryo transfering. The pregnancy rates of the recipients receiving the in vitro produced embryos of the Healthy Holstein dairy cows and Wagyu cattle were measured on day 45 after embryo transfering. [Result] Addition of 30 U/mL leptin in the culture medium significantly （P<0.05） increased the blastocyst rate of the in vitro cultured cattle embryos of slaughterhouse origin. For the donors, 7.5 and 8.1 usable oocytes were averagely obtained per Holstein dairy cow and per Wagyu cattle, respectively. The cleavage rates of Holstein dairy cow and Wagyu cattle were 84.00% and 82.71%, respectively, and there was no significant （P>0.05） difference between them. Under the in vitro conditions, 4.3 and 3.7 available blastocysts were averagely obtained per Holstein dairy cow and per Wagyu cattle, respectively, and the blastocyst rate of Holstein dairy cow （57.33%） was significantly （P<0.05） higher than that of Wagyu cattle （45.68%）. The pregnancy rates of Holstein dairy cow embryo group and Wagyu cattle embryo group were 54.17% and 55.79%, respectively, and no significant （P>0.05） difference was observed. [Conclusion] The established OPU/IVF system effectively improves the utilization efficiency of high-quality female cattle, reduces its production costs, and provides references for the optimization of in vitro embryo production system for cattle.

[Objective] This study was conducted to assess the effects of dietary sodium chloride level on the growth performance as well as the microbial community diversity in the larval intestine and feeding substrate of black soldier fly （Hermetia illucens L.）. [Method] The black soldier flies fed with the diet without extra addition of sodium chloride was set as control group, and the ones fed with the diets added with 0.7% and 2.0% sodium chloride were set as experimental groups. The experimental period was from 6-day-old larvae to adult laying eggs. The indexes associated with growth performance and growth cycle of the flies fed with the diets containing different levels of sodium chloride were statistically analyzed, and 16S rDNA sequence analysis technique was used to characterize the changes of microbial communities in the larval intestine and feeding substrate. [Result] ①The body length, body weight （except for 9-day-old）, feed conversion rate, feed utilization rate, feed to weight gain ratio, larval fresh mass and total fresh mass gain, protein content, fat content, survival rate, pupation rate, eclosion rate, eclosion time, and oviposition time of the 0.7% sodium chloride addition group were not significantly （P>0.05） different from those of the control group. ②Compared with the control group, in the 2.0% sodium chloride addition group, both the body length and weight of the 9- to 18-day-old larvae were significantly （P<0.05） decreased; the feed weight loss rate and apparent digestibility were significantly （P<0.05） reduced; the feed conversion rate was significantly （P<0.05） increased; there was no significant （P>0.05） changes in feed utilization rate and feed to weight gain ratio; the fat content was significantly （P<0.05） elevated; the larval fresh mass, total fresh mass gain, and protein content had no significant （P>0.05） changes; the survival rate, pupation rate, and eclosion rate were significantly （P<0.05） decreased, and the eclosion time and oviposition time extended by 2 d （P<0.05）. ③In 0.7% sodium chloride addition group, at phylum level, the relative abundance of Proteobacteria in the larval intestine was decreased from 92.33% to 82.53%, and that of Firmicutes was increased from 6.55% to 14.88% compared with the control group; the relative abundance of Firmicutes in the feeding substrate was increased from 23.42% to 28.07%, while that of Bacteroidetes was decreased from 41.57% to 37.92%. At genus level, the relative abundance of Providencia in larval intestine was decreased from 79.90% to 76.92%, and that of Morganella and Enterococcus was decreased from 8.27% to 5.34% and increased from 4.98% to 6.62%, respectively; the relative abundance of Alcaligenes in the feeding substrate was increased from 2.73% to 12.10%, and that of Pseudomonadaceae_Pseudomonas was decreased from 3.59% to 1.46%. ④In 2.0% sodium chloride addition group, at phylum level, the relative abundance of Proteobacteria in the larval intestine was decreased from 92.33% to 59.13%, and that of Firmicutes was increased from 6.55% to 34.69% compared with the control group; the relative abundance of Bacteroidetes in the feeding substrate changed greatly, decreasing from 41.57% to 11.11%. At genus level, the relative abundance of Providencia in the larval intestine was decreased from 79.90% to 29.36%, and that of Morganella was increased from 8.27% to 27.23%; the relative abundance of Corynebacterium in the feeding substrate changed greatly, increasing from 0.01% to 6.90%. [Conclusion] Dietary addition of 0.7% sodium chloride had no affects on the growth performance of black soldier fly. While the addition of 2.0% sodium chloride in diet inhibited the larval growth and greatly affected the microbial communities in larval intestine and feeding substrate.

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

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

Plant essential oils are characterized by favorable antibacterial, anti-inflammatory, and antioxidant properties. As feed additives for livestock and poultry, they have such advantages as good safety, high efficacy, minor toxic and side effect, and low residue level, giving them great development potential and research value in becoming substitutes for in-feed antibiotics. This paper introduces the physicochemical properties of plant essential oils, summarizes the plant essential oil microencapsulation process and preparation methods, and reviews the research progress in application of plant essential oils in livestock and poultry farming, in hoping to provide references for the research and development of plant essential oil microcapsule preparations for livestock and poultry use and for the scientific application of plant essential oils in livestock and poultry production.

China is the largest potato （Solanum tuberosum） producer in the world, and potato production brings a large number of by-products. With the continuous improvement of the scale of livestock and poultry farming in China, the demands for feed raw materials are increasingly growing. Potato by-products are rich in crude fiber, crude fat and amino acids, and contain certain amount of minerals. As an unconventional roughage for ruminants, they have gradually received concerns. However, due to the lagging development and utilization technology of potato by-products, their feeding value and utilization rate are still limited. Therefore, how to improve the utilization rate of potato by-products and give full play to their feeding and nutritional value are urgent problems to be solved. In this paper, the research progress in forage utilization of potato by-products, such as potato straw, potato residue, potato starch residue and starch, and potato protein are reviewed, in hoping to provide references for the further study on forage utilization of potato by-products.

Flavonoid compounds exist in a variety of plants in nature. They are a class of important natural active ingredients with a range of biological activities, such as anti-oxidation, anti-inflammation, antibiosis, anti-tumor, immune regulation, and have a wide range of application. The source, structure, classification, extraction techniques, biological activity of flavonoid compounds as well as their applications in medicine and animal production are reviewed, in hoping to provide references for further research and development of flavonoid compounds.

Skeletal muscle is the main component of the animal body. The development process of muscle fiber in skeletal muscle is lengthy and regulated by various factors. Genes involved in the muscle fiber development in livestock and poultry have relatively complex regulatory mechanisms, and these genes are also regulated by other factors. The relevant regulators may not be sufficient in livestock and poultry, so exogenous substances need to be added to promote muscle fiber development. By integrating research literature on muscle fiber development both domestically and internationally in the past 5 years, combined with the characteristics of genes related to muscle fiber development, this paper introduces the exogenous substances that affect the development of muscle fiber in livestock and poultry, emphasizes the regulatory effects of these exogenous substances on muscle fiber development, and prospects the research on the regulation of genes related to muscle fiber development, in hoping to provide references for future study.

Capacitation is a crucial stage before sperm and egg cell complete fertilization in mammals. A series of physiological and biochemical processes are altered in accompany with sperm capacitation, including ion content changes, plasma membrane remodeling, cholesterol efflux, and protein tyrosine phosphorylation. In addition, decapacitation factors enable sperms to successfully complete fertilization. These alternations can be used to detect sperm capacitation status. The commonly used methods include the detections of sAC-cAMP-PKA pathway, plasma membrane fluidity change, cholesterol redistribution, tyrosine phosphorylation, and acrosome reaction. This article reviews the research progress in signaling pathways, signaling molecules, regulatory factors, ion channels, and sperm capacitation detection methods involved in sperm capacitation in mammals, and prospected the main research directions in the future, in hoping to provide references for sperm in vitro culture and the application of assisted reproductive technology.

[Objective] The present study was conducted to propose a method for organizing the knowledge of animal husbandry laws and regulations to achieve a more orderly organization of relevant knowledge. [Method] The online legal resources in the websites of flk.npc.gov.cn, pkulaw.com, lawyee.org, wkinfo.com.cn, and law.cnki.net were used as the data sources of animal husbandry laws and regulations, the relevant laws and regulations of animal husbandry were screened and obtained. Subsequently, the corresponding formulation authority, timeliness, effectiveness hierarchy, regulation category, issuing date, implementation date and year information were extracted, and the obtained data was preprocessed. The ontology was built, and the entities and relationships were defined. Using rule-based method, the entities and relationships from the obtained laws and regulations texts were extracted, and then temporarily stored in MySQL database. The SQLAlchemy database and py2neo database in Python were used to operate MySQL database and Neo4j Graph database to convert the data in MySQL into entity relationship triad, and then stored in Neo4j Graph database to complete the storage of knowledge graph of animal husbandry laws and regulations. [Result] A total of 287 laws and regulations related to animal husbandry were collected and classified based on whether the laws and regulations contained chapters. Among these, 211 laws and regulations contained chapters, totaling 1 470 chapters and 10 457 articles, whereas 76 laws and regulations did not contain chapters, totaling 2 145 articles. There were 10 types of entities defined, including ′laws and regulations′, ′issuing authority′, ′timeliness′, ′effectiveness hierarchy′, ′regulation category′, ′chapter′, ′article′, etc. There were 10 types of relationships defined, including ′the relationship of animal husbandry laws and regulations to category of laws and regulations ′, ′the relationship of animal husbandry laws and regulations to timeliness of laws and regulations′, ′the relationship of animal husbandry laws and regulations to issuing authority of laws and regulations′, and ′the relationship of animal husbandry laws and regulations to effectiveness hierarchy of laws and regulations′, etc. A knowledge graph of animal husbandry laws and regulations covering 14 936 entities and 16 339 relationships was constructed. [Conclusion] This method can be applied to organize the knowledge on animal husbandry laws and regulations, making the organization of knowledge more systematic and closely related.

[Objective] This study was conducted to investigate the heavy metal pollution of the roadside soil in a typical grassland with dominant species of Stipa capillata and Leymus chinensis in Xianghuang Banner, Xilin Gol League, Inner Mongolia, and to provide references for soil remediation of typical grassland. [Method] In the research area, five experimental plots on both sides of National Trunk Highway G511 were selected. Four heavy metal ecological risk assessment methods （single factor index, Nemerow composite index, potential ecological risk index, and land accumulation index） were used to assess the ecological risk of soil in the research area. [Result] The soil contents of eight heavy metal elements（As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn） in the research area exceeded the soil background values in Xilin Gol League, Inner Mongolia, and were lower than the first-class standard of national soil environmental quality. The single factor index and land accumulation index were Cd>Hg>Cu>Zn>Cr>As>Ni>Pb, and the potential ecological risk index was Cd>Hg>As>Cu>Ni>Pb>Cr>Zn. [Conclusion] The Cd element in the research area had a higher ecological risk.

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

[Objective] This study was conducted to assess the effects of different herbicides on the above-ground biomass accumulation and medicinal material yield of Astragalus membranaceus, and to evaluate their weed control efficacy in Astragalus membranaceus fields. [Method] Five types of post-emergence herbicides, including Herb Weed No.1 （YCC）, bentazone （MCS）, clethodim （XCT）, haloxyfop （GCN）, and sethoxydim （NBJ）, were applied on the annual Astragalus membranaceus var. mongholicus transplanted seedlings according to the recommended concentrations. Water was sprayed as the control （CK）. Each herbicide application treatment was repeated 3 times and a total of 18 experimental blocks were set. At the beginning of June 2021, the quadrat method was used to determine the number of plant, fresh mass, and dry mass of weeds in each experimental block. On July 10^th, August 10^th, and September 10^th in the same year, the above-ground biomass fresh weight and dry weight of Astragalus membranaceus var. mongholicus in each experimental block were measured. In the harvest season （November in the same year）, the fresh weight and dry weight of medicinal material of Astragalus membranaceus var. mongholicus in each experimental block were calculated. Variability analysis and single factor analysis of variance were utilized to assess the statistical data. [Result] The five herbicides had varying weed control efficacy, among which the YCC treatment group had the best, with stem control effect of 77.81%, fresh mass control effect of 64.48%, and dry mass control effect of 80.81%. There were no significant （P>0.05） differences in the above-ground biomass fresh weight, dry weight, and fresh-dry ratio of Astragalus membranaceus var. mongholicus across the different herbicide treatment groups in July, August and September. In November, the fresh weight and dry weight of medicinal material of Astragalus membranaceus var. mongholicus in the YCC treatment group were significantly （P<0.05） higher than those in the other treatment groups. [Conclusion] The application of Herb Weed No.1 displayed superior weed control efficacy in the transplanted fields of Astragalus membranaceus var. mongholicus, with notable promoting effects on the above-ground biomass and medicinal material yield.

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

[Objective] This study aimed to explore the biodiversity of yeasts in sour whey, a by-product of traditional cheese processing in the pastoral area of Xilin Gol League, Inner Mongolia. [Method] The yeasts were isolated and purified from two sour whey samples collected in Xilin Gol League, Inner Mongolia, using traditional isolation and culture technology of microorganisms. The species of the isolated yeast strains was determined by ITS gene sequence analysis, and a phylogenetic tree was constructed. [Result] A total of 18 yeast strains were obtained from the two sour whey samples, belonging to 4 different species, Saccharomyces cerevisiae （n=2）, Pichia fermentans （n=2）, Pichia kudriavzevii （n=2） and Kluyveromyces marxianus （n=12）. Among them, Kluyveromyces marxianus was the dominant flora in the sour whey samples. [Conclusion] Our results reveal the biodiversity of yeasts in sour whey collected in Xilin Gol League, Inner Mongolia, and provide references for the comprehensive utilization and industrial production of sour whey.

[Objective] This study was conducted to isolate and identify Escherichia coli strains from the fecal samples of the racing horses in an equestrian club in Guangzhou City, and to characterize the virulence genes and antimicrobial resistance profile of the isolates. [Method] A total of 20 fecal samples were collected from the adult racing horses in an equestrian club in Guangzhou City. The bacterial culture technology, Gram staining and microscopy examination, and 16S rDNA PCR amplification and sequencing method were employed to isolate and identify the Escherichia coli strains. Subsequently, the Escherichia coli phylogenetic group identification was performed on the isolates, and the presence of 10 virulence genes and 11 antimicrobial resistance genes in the isolates was detected using PCR assay. In addition, the antimicrobial susceptibility test of the isolates was carried out using K-B disk method. [Result] A total of 13 Escherichia coli strains were isolated and identified by morphological observation and PCR detection, with an isolation rate of 65.00% （13/20）. The phylogenetic group identification demonstrated that the 13 Escherichia coli isolates were classified as group A （23.07%, 3/13）, group B1 （61.54%, 8/13）, and group D （15.38%, 2/13）, respectively. In the isolates, 5 virulence genes including fimC （61.54%, 8/13）, fyuA （7.69%, 1/13）, irp2 （7.69%, 1/13）, stx1 （15.38%, 2/13）, and stx2 （7.69%, 1/13） were detected, and 9 antimicrobial resistance genes including parC （100%, 13/13）, gyrA （100%, 13/13）, gyrB （92.31%,12/13）, sul2 （76.92%, 10/13）, cmlA （30.77%, 4/13）, aadA （23.07%, 3/13）, tet （B） （15.38%, 2/13）, bla_TEM （7.69%, 1/13）, and bla_CTX （7.69%, 1/13） were detected. Among the 13 Escherichia coli isolates, 38.46% of them were resistant to tetracycline, and 30.77% of them were resistant to ceftiofur, amikacin, and ampicillin. Different levels of resistance to chloramphenicol, trimethoprim/sulfafurazole, and imipenem was also observed. All of the isolates were susceptible to cefoxitin, gentamicin, and ciprofloxacin. [Conclusion] The community of the horse origin Escherichia coli strains isolated from the racing horses in this equestrian club was diversified. The isolates harbored multiple virulence genes and antimicrobial resistance genes, and exhibited multi-drug resistance. Our results suggest that the prevention and treatment of horse colibacillosis should be strengthened in clinical practice.

[Objective] This study was conducted to identify the pathogenic bacteria isolated from the feces of diarrheal piglets in a farm in Xinjiang, and to understand their biological characteristics. [Method] Four faecal samples were collected from the diarrheal piglets in this farm, and the bacteriological culture technology and PCR assay were used to isolate and identify the bacterial pathogens. In addition, the antimicrobial susceptibility test and virulence gene detection were carried out for the isolated strains. [Result] After the bacteriological culture, three suspected strains were obtained. On xylose-lysine deoxycholate agar medium, the colonies were pale yellow with smooth and shiny surroundings as well as a black center. Gram stain demonstrated that they were short-rod-shaped Gram negative bacteria with blunt round ends. The SSU rDNA sequences of the three isolated strains had 100% homology with the SSU rDNA sequence of a Proteus mirabilis strain isolated from Caracal caracal in Guangdong Province, China. Combining morphological observation and SSU rDNA sequence analysis, the three obtained isolates, designated as NO.1, NO.2 and NO.3 strains, were identified as Proteus mirabilis. The three Proteus mirabilis isolates were resistant to eleven of the twelve antimicrobial agents, including norfloxacin, midecamycin, erythromycin, etc. The NO.2 and NO.3 strains were susceptible to cefoxitin, and the NO.1 strain was intermediate to cefoxitin. All the three isolates harbored seven virulence genes of ureC, pmfA, zapA, mrpA, atfA, atfC, and ucaA. [Conclusion] The three Proteus mirabilis strains isolated from piglets had multiple antimicrobial resistance and carried multiple virulence genes, indicating that Proteus mirabilis was one of the pathogens causing diarrhea in piglets. Attentions should be paid in the rational use of antibiotics.

[Objective] The aim of this study was to understand the prevalence of Anaplasma infection in ticks and sheep in Aksu Prefecture of Xinjiang Uygur Autonomous Region. [Method] A total of 192 ticks and 477 sheep anticoagulant blood samples were collected. After morphological identification, the ticks were molecularly confirmed by using PCR assays targeting mitochondrial 16S rDNA and ITS-2 genes. The presence of Anaplasma ovis （A. ovis） and Ananlasma phagocytophilum （A. phagocytophilum） in the ticks and sheep anticoagulant blood samples were detected by using conventional PCR assay and nested PCR assay with specific primers, respectively. Statistical analysis were performed to assess the the differences in prevalence of A. ovis and A. phagocytophilum among ticks of different genders as well as sheep reared in various regions and feeding modes. [Result] The 192 ticks, including 79 male ticks and 113 female ticks, belonged to 2 genera and 3 species. The number of ticks identified as Rhipicephalus turanicus （R. turanicus）, Hyalomma asiaticm （H. asiaticm） and Hyalomma anatolicum （H. anatolicum） accounted for 52.60%, 45.83% and 1.56% of the total, respectively. In the tick samples, the overall positive rate of Anaplasma infection was 7.29%, while the mixed infection of A. ovis and A. phagocytophilum was not observed; the positive rates of Anaplasma infection for R. turanicus, H. asiaticm, and H. anatolicm were 8.91%, 5.68%, and 0, respectively, with statistically significant differences （χ²=3.20, P<0.05）; the positive rates of Anaplasma infection for male and female ticks were 6.33% and 7.96%, respectively, with no statistically significant difference （χ²=0.30, P>0.05）. In the sheep anticoagulant blood samples, the overall positive rate of Anaplasma infection was 51.15%, which had statistically significant difference with that of the tick samples （χ²=111.35, P<0.05）; the mixed infection rate of A. ovis and A. phagocytophilum was 16.56%; the positive rates of Anaplasma infection in captive and free range sheep were 28.16% and 83.00%, respectively, with statistically significant difference （χ²=139.81, P<0.05）; Kuqa City and Xayar County had the lowest positive rate of Anaplasma infection at 5.00%, and Wensu County had the highest positive rate at 64.83%, with statistically significant difference （χ²=27.72, P<0.05）. [Conclusion] The prevalence of Anaplasma infection in ticks and sheep in Aksu Prefecture was common, and the prevention and control of anaplasmosis should be strengthened.