This study aimed to discover the functional genes potentially associated with mare early abortion. Ten mares that had the presence of embryo at 45^th day after mating but miscarried two to four months after mating and ten mares that normally delivered were selected from the same confined rearing horse herd. Blood samples from the selected mares were collected, and the genomic DNA was extracted. The average sequencing depth of the whole genome was 10×, the genome coverage was over 97%, and about 4×10⁶ SNPs were obtained from each sample. The whole genome resequencing data between the mares in miscarriage group and normal delivery group were compared. The results showed that Fst analysis obtained 1 381 SNPs, π analysis obtained 1 614 SNPs, and the combinative analysis of Fst and π obtained 203 SNPs; by filtering out the intergenic regions of mutagenesis, non-coding regions, introns and synonymous SNVs, a total of 82 SNPs locating on 69 genes were found; through GO term, signal pathway enrichment analysis and literature review, 12 genes were considered as important candidate genes involved in early abortion and embryo implantation in mares; the screened candidate genes affected the embryo implantation by ways such as participating in hormone regulation, embryo invasion, vitamin anabolism. The results of this study provide reference data in bioinformatics for unraveling the molecular mechanism underlying the causes of early abortion in mares.

A real-time fluorescence quantitative PCR assay to quantify the antigen concentration of inactivated porcine circovirus type 2 vaccines was developed based on a set of primers and TaqMan probe designed targeting the Cap gene sequence of porcine circovirus type 2 from GenBank. After optimizing the reaction system, the specificity, sensitivity and repeatability of the established assay were assessed. Subsequently, the impacts of adding amount of inactivator and inactivation time on detection performance of the established assay were investigated. The results showed that positive amplification product was exclusively obtained for target gene of porcine circovirus type 2 by using the established real-time fluorescence quantitative PCR assay, while the other three kinds of porcine origin viruses had no expected amplification products; the sensitivity of the established assay reached up to 10^2.0 TCID₅₀/mL, which was 100 times higher than that of the ordinary PCR assay; the established assay had good repeatability with the variable coefficient of 2.28% in 10 repeated tests for the same one sample; the different adding amount of inactivator and inactivation time had limited impacts on detection performance of the established assay, in other words, the creditability of the inactivated vaccine comparison test was not affected by the adding amount of inactivator recommended by varied vaccine producers and different inactivation time. In this study, a real-time fluorescence quantitative PCR assay to quantify the antigen concentration of inactivated porcine circovirus type 2 vaccines is successfully developed. This established assay can quantitatively discriminate the antigen concentration of different inactivated porcine circovirus type 2 vaccine samples, providing novel insight into the development of quantitative evaluation method for antigen concentration of inactivated porcine circovirus type 2 vaccines.

This study was conducted to establish a preparation technique for donkey bone collagen polypeptides, and to determine the molecular weight of the products. Using bovine serum albumin as a reference substance, the standard curve equation between polypeptide contents and ultraviolet absorption values at OD_{650 nm} was established; under the condition of artificial gastric juice and artificial intestinal juice, using the polypeptide content of primary enzymatic hydrolysates and secondary enzymatic hydrolysates as evaluative indicator, the donkey bone collagen polypeptides were prepared with secondary bio-enzymatic hydrolysis technology after determining the optimum enzymolysis time and adding amount of pepsin and trypsin; the molecular weight of the prepared donkey bone collagen peptides was detected by using SDS-PAGE. The results showed that the established standard curve equation between polypeptide contents and ultraviolet absorption values at OD_{650 nm} was y=0.163 9x-0.149 6, R²=0.998 9; the optimum conditions for primary enzymatic reaction were as follows the pH value ranged from 2.5 to 3.0, the adding amount of pepsin was 2.0%, and the enzymolysis time was 2.0 h; the optimum conditions for secondary enzymatic reaction were as follows the pH value ranged from 7.5 to 8.0, the adding amount of trypsin was 2.0%, and the enzymolysis time was 2.5 h; by using SDS-PAGE, the molecular weight of the donkey bone collagen polypeptides prepared with the above optimal reaction conditions was determined as about 10 kDa. Our research provides a technical reference for the development of donkey bone collagen polypeptide materials with molecular weight suitable for human absorption and the subsequent products.

The purpose of this study was to assess the effects of compound enzymes with different zymograms on growth performance, serum biochemical indexes and number of intestinal flora of broilers. A total of 480 28-day-old white-feathered broilers were selected and randomly divided into 4 groups with 12 replicates in each group and 10 broilers （half males and half females） in each replicate. The broilers in control group were fed with a corn-soybean meal diet, and those in experimental groups Ⅰ, Ⅱ and Ⅲ fed the same basal diet as control group were supplemented with 200 g/t compound enzymes with different zymograms. The experimental period was 15 days (28 to 42 days of age of the broilers). The ratio of feed to gain, serum biochemical indexes and number of intestinal flora of broilers in different groups were determined and statistically compared. The results showed that compared with the control group, the ratio of feed to gain of experimental groups Ⅰ, Ⅱ and Ⅲ was extremely significantly decreased by 1.01% （P<0.01）, 2.20% （P<0.01） and 0.83% （P<0.01）, respectively; there was extremely significant （P<0.01） difference in ratio of feed to gain among experimental group Ⅱ and experimental groups Ⅰ and Ⅲ. Compared with the control group, the total protein and albumin contents of experimental groups Ⅰ, Ⅱ and Ⅲ were extremely significantly increased by 10.08%-11.41% （P<0.01） and 12.00%-12.93% （P<0.01）, respectively. Compared with the control group, the number of intestinal Escherichia coli in experimental groups Ⅰ, Ⅱ and Ⅲ was extremely significantly decreased by 17.87% （P<0.01）, 26.43% （P<0.01） and 21.67% （P<0.01）, respectively; extremely significant （P<0.01） difference in number of intestinal Escherichia coli between experimental group Ⅰ and experimental group Ⅱ was observed, and significant （P<0.05） difference was also found among experimental group Ⅲ and experimental groups Ⅰ and Ⅱ. Compared with the control group, the number of intestinal Lactobacillus in experimental groups Ⅰ, Ⅱ and Ⅲ was extremely significantly increased by 13.99% （P<0.01）, 26.10% （P<0.01） and 24.06% （P<0.01）, respectively; there was extremely significant （P<0.01） difference in number of intestinal Lactobacillus among experimental group Ⅰ and experimental groups Ⅱ and Ⅲ. In summary, the dietary supplementation of compound enzymes with different zymograms had certain improving effects on growth performance, serum biochemical indexes and number of intestinal flora of broilers. Furthermore, the compound enzymes with different zymograms have varied performance in improving the production performance associated indexes of broilers. The results obtained in this study provide references for collocation of high-efficient compound enzymes in practical production.

This study aimed to assess the effects of different pelleted diets on growth performance, nutrient apparent digestibility and serum biochemical indexes in fattening sheep. A total of 60 wether lambs at ages of 70±10 days of Tan sheep with similar weights were selected and randomly divided into control group （n=15）, experimental group Ⅰ （n=15）, experimental group Ⅱ （n=15） and experimental group Ⅲ （n=15）. The control group fed 100% self-prepared total mixed ration （40% self-prepared concentrate + 60% self-prepared forage）, experimental group Ⅰ fed 50% self-prepared total mixed ration （20% self-prepared concentrate + 30% self-prepared forage） + 50% commercially available total mixed pelleted diet for fattening sheep, experimental group Ⅱ fed 100% commercially available total mixed pelleted diet for fattening sheep, and experimental group Ⅲ fed 45% pelleted concentrate supplement + 55% pelleted forage. The feeding experiment included a 16 days pre-test period and an 87 days formal test period. The experimental fattening sheep in different groups were weighed at the beginning and end of the experiment, and the average daily gains during the feeding experiment were calculated. The feed intakes were observed and recorded, and the average daily feed intakes and feed/gain were calculated. At the end of the feeding experiment, the apparent digestibility of dry matter, organic matter, crude protein and neutral detergent fiber as well as the serum biochemical indexes were determined using routine methods. The indictors associated with growth performance, nutrient apparent digestibility and serum biochemical indexes among different groups were statistically compared. The results showed that the highest average daily gain was observed in experimental group Ⅱ, which was significantly （P<0.05） higher than those of experimental group Ⅰ and experimental group Ⅲ, and was extremely significantly （P<0.01） higher than that of control group; the average daily feed intake of experimental group Ⅱ was significantly （P<0.05） lower than those of experimental group Ⅰ and control group; the experimental group Ⅱ had the lowest feed/gain, which was decreased by 60.63%, 35.69% and 9.41% compared to control group, experimental group Ⅰ and experimental group Ⅲ, respectively. The apparent digestibility of dry matter, organic matter, crude protein and neutral detergent fiber of experimental group Ⅱ were higher than those of the other three groups, and significant （P<0.05） difference was observed in apparent digestibility of crude protein. There were no significant （P>0.05） differences in serum biochemical indexes among different groups. In summary, feeding total mixed pelleted diet improves the growth performance and increases the nutrient apparent digestibility of the fattening Tan sheep, and has no obvious affection on their health.

The objective of this study was to assess the effects of the addition of Lactobacillus buchneri and cellulase on fermentative quality and aerobic stability of silage corn straw. A fermentative experiment using silage corn straw as raw material was conducted with four groups control group （CK）, Lactobacillus buchneri addition group （LB）, cellulase addition group （ENZ）, and Lactobacillus buchneri + cellulase combinative addition group （LB + ENZ）. After a 45-day-long fermentation, the fermented silage corn straw samples of different groups were collected for comprehensive sensory evaluation of fermentative quality. The pH value, organic acid content, viable bacterial cell count, water-soluble carbohydrate （WSC） content, neutral detergent fiber （NDF） content and acid detergent fiber （ADF） content were determined and statistically compared. The results showed that the comprehensive sensory score of LB group, ENZ group and LB+ENZ group was 20.31%, 14.06% and 25.00% higher than that of CK group, respectively. The viable yeast counts of LB group and LB+ENZ group were decreased to 2.23×10³ CFU/g FM and 7.10×10² CFU/g FM, respectively, and both of them were obviously lower than those of CK group and ENZ group. Compared with CK group, LB group and LB+ENZ group had significantly （P<0.05） increased acetic acid content, and had significantly （P<0.05） reduced lactic acid/acetic acid and ammonia nitrogen （NH₃-N） content; the production of propionic acid of LB group and LB+ENZ group was also inhibited. Compared with CK group, ENZ group and LB+ENZ group had significantly （P<0.05） better degradation effect on ADF, while no significant （P>0.05） difference in degradation effect on NDF was observed; the WSC contents of ENZ group and LB+ENZ group were elevated. The aerobic stability time of LB+ENZ group, LB group and ENZ group was increased by 312.36%, 250.56% and 87.64% compared to CK group, respectively, and statistically significant （P<0.05） inter-group differences among the four groups were observed. In conclusion, the combinative addition of Lactobacillus buchneri and cellulase can improve the fermentative quality and aerobic stability of silage corn straw.

This study was conducted to assess the effects of dietary supplementation with 5 different rates of probiotic fermentation feed prepared with Kinggrass No.1 on production performance and feeding economic benefit of black pig. A total of 180 healthy binary hybrid black pigs with similar weight were selected and randomly divided into 6 groups with 3 replicates for each group and 10 individuals for each replicate. The control group was fed with the basal diet, and the experimental groups of Ⅰ, Ⅱ, Ⅲ, Ⅳ and Ⅴ were fed with the basal diet supplemented with 10%, 20%, 30%, 40% and 50% probiotic fermentation feed prepared with Kinggrass No.1, respectively. The feeding experiment was composed of a 7 days pre-test period and a 60 days formal test period. The average daily gain, average daily feed intake, diarrhea rate, dressing percentage and feeding gross profit of different groups were calculated and compared. The results showed that, except for experimental group Ⅲ （P>0.05）, statistically significant （P<0.05） differences in average daily gain between the other 4 experimental groups and the control group were found; the highest average daily gain was observed in experimental group Ⅱ （865.24 g per pig）, followed by experimental group Ⅰ （839.33 g per pig）, increased by 23.24% and 19.55% respectively compared with control group; the lowest average daily gain was observed in experimental group Ⅴ （552.51 g per pig）, which was decreased by 21.31% compared with control group. The highest and lowest average daily feed intakes were observed in experimental group Ⅴ （3.35 kg per pig） and control group （2.30 kg per pig）, and there were statistically significant （P<0.05) differences in average daily feed intake between the 5 experimental groups and control group. In terms of dressing percentage, statistically significant （P<0.05） inter-group differences were observed among experimental groups Ⅲ, Ⅳ and Ⅴ, while no statistically significant （P>0.05） difference between experimental group Ⅰ and experimental group Ⅱ was found; with the increase of supplementation rate of probiotic fermentation feed prepared with Kinggrass No.1, the dressing percentage of the black pigs exhibited a deceasing trend; the control group and experimental group Ⅴ had the highest and lowest dressing percentage, respectively. The highest feeding gross profit was obtained in experimental group Ⅱ （21 259.0 Yuan）, and the lowest feeding gross profit was obtained in experimental group Ⅴ （10 325.7 Yuan）. In summary, 20% dietary supplementation of probiotic fermentation feed prepared with Kinggrass No.1 has the best performance in improving production performance of fattening black pig and obtains the best feeding economic benefit.

Tryptophan is an aromatic amino acid which is essential for the maintenance of physiological functions such as feed intake, growth and immunity as well as for protein synthesis. Tryptophan has become the main limiting amino acid in feed due to the large use of synthetic methionine and lysine in formulated feed. Accurate determination of tryptophan is very important for dietary protein balance. This paper reviews the analytical methods of tryptophan in recent years, including ultraviolet or fluorescence spectrophotometer, near infrared spectroscopy, amino acid analyzer, high performance liquid chromatography, gas chromatography-mass spectrometry, capillary electrophoresis and other methods, in hoping to provide reference for nutritional value evaluation and quality control of feed.

Feed acidifier is a kind of environment-friendly additive which has no residue and no drug resistance. It participates in metabolism of sugar, protein and fat in animal body, and has some advantages in replacing antibiotics. This paper summarized the types, action mechanisms and application advantages of feed acidifiers, in hoping to provide theoretical reference for enriching the antibiotic replacing schemes in feed.

Xing'an multi-lamb sheep is a new mutton sheep breed which is suitable for large-scale confined feeding in northeast regions of Inner Mongolia, which is typically characterized by high reproduction rate, fast growth and development, and good feeding benefit. In order to quantitatively analyze the reproduction performance and feeding benefit of Xing'an multi-lamb sheep, this study conducted a comprehensive analysis on the lambing data of Xing'an multi-lamb sheep collected from year 2018 to 2019 in Inner Mongolia Dumei Animal Husbandry Biotechnology Co., Ltd.. Through calculation, the multiple lambing rate of primiparous ewes was 80.48%, and that of multiparous ewes was 88.51%. The average litter size per ewe was 2.18 lambs, and 4.02 lambs were obtained per ewe per year. The average birth weight, weaning weight and average daily gain of 50-day-old lambs were 3.98 kg, 14.32 kg and 229.78 g, and the LEY index was 3.26. The net feeding profit of adult ewe was 2 367 Yuan per sheep per year. The results showed that Xing'an multi-lamb sheep has a good breed advantage and is suitable for large-scale promotion in northeast regions of Inner Mongolia.

The purpose of this study was to characterize the inter-monthly variation of milk composition, somatic cell count and total bacterial count in Holstein dairy cows in Hulun Buir region of Inner Mongolia. A total of 14 354 batches of samples were collected from January to December in year 2019 and used to assess the variations of milk yield, composition, somatic cell count and total bacterial count in different months. The results showed that the milk yield of Holstein dairy cows in Hulun Buir region had an obvious inter-monthly difference; the highest milk yield was observed from April to May; the lowest milk yield was observed from November to February of the following year, and protective measures against the cold stress were recommended in this duration; higher level of milk somatic cell count was observed from January to March, accordingly, the feeding management of dairy cows was expected to be strengthened, and the prevention and control measures against mastitis was supposed to be taken; milk composition and total bacterial count hardly varied among different months.

With the continuous expansion of intensive rearing scale of dairy cows, the produced excrements cause serious pollution to the surrounding environment. Fermentation bed technology is a new type of environment-friendly cattle raising model. By using this technology, the excrements produced by livestock and poultry are fermented with microorganisms, achieving the disposal-free of the feces and urine in the shed and effectively solving the environmental pollution problem caused by large-scale animal rearing. In this paper, the principles, commonly used microorganisms, management measures and application effect of fermentation bed technology are summarized, and the existing problems and corresponding strategies in the process of dairy cow excrement treatment and resource utilization are analyzed and put forward, in hoping to provide references for intensive and healthy rearing of dairy cow.

[Objective] To evaluate the killing effect of microcurrent against bacteria in water body, and to provide basis for developing new disinfection techniques for livestock and poultry sewage. [Method]Suspension quantitative bactericidal test, influencing factors determination test and simulated field test were conducted to assess the killing effect of microcurrent against Escherichia coli （E. coli）, Staphylococcus aureus （S. aureus）, Pseudomonas aeruginosa （P. aeruginosa） and Bacillus subtilis （B. subtilis）, to evaluate the impact of temperature and pH value on disinfection effect, and to investigate the disinfection effect of microcurrent on artificial lake water and waste water from livestock and poultry farms.[Result]The killing log values against the above 4 bacterial suspension were all higher than 5.0 after the treatment of microcurrent for 4 min. Temperature and pH value had no impacts on disinfection effect of microcurrent. After the treatment of microcurrent for 4 min, 99.99% of the total bacteria in the artificial lake water and waste water from livestock and poultry farms were killed, indicating that the bacteria in the water samples were almost killed. When treatment duration extended to 5 min, the total number of bacterial colonies in the water samples were reduced to 0 CFU/mL, indicating that the bacteria in the water samples were completely killed. [Conclusion]Microcurrent has killing effect against the commonly observed bacteria in livestock and poultry sewage, and has broad application prospect in disinfection in livestock and poultry rearing industry.

Nematodes are some of the most abundant invertebrates on the earth and play an important role in agricultural and forestry production. Soil nematode community is closely related to environment. The environmental factors （such as soil moisture, temperature, physical and chemical properties, vegetation and food conditions）, and the comprehensive effects of environmental factors（such as succession stage and interference） all have important impacts on the life activities and community distribution of soil nematodes. In this paper, the recent research progress in effects of environmental factors on soil nematode community in China and abroad is summarized and reviewed. On this basis, the focus of future research that how specific environmental factors affect the life activities and community distribution of soil nematodes is put forward.

This paper introduces the desertification and degradation of land and grassland as well as the existing amount of shrub resources in Inner Mongolia, summaries the present situation of forage utilization of desert shrub resources in China and abroad, analyzes the ecological and economic effects of developing shrub feed in Inner Mongolia, in hoping to provide a theoretical basis for forage utilization of desert shrub resources.

The family rangelands distributed in two grassland types of typical steppe and dessert steppe in Siziwang Banner of Inner Mongolia were used as research objects in this study. By field investigation of herdsmen, establishment of simulation analysis modeling and consultation of literatures, the parameters of grassland, livestock, feed, meteorology and economy were thoroughly assessed, and the grassland growth rate, energy balance status between forage and livestock as well as economic benefit were simulated, in hoping to provide reliable basis for guiding the sustainable management of local family rangelands. The results showed that the forage growth cycle in Siziwang Banner was relatively short. In summer, the forage growth rate in typical steppe area was higher than that in desert steppe area. The forage in the two types of grassland had poor cold-resistant capability, the growth of the most forage was hardly observed, and the above-ground parts of the forage were basically dead during winter time. Accordingly, for the raised livestock, energy obtained from the fresh forage was mainly concentrated in summer and autumn which were the forage growing seasons. Small- and medium-sized family rangelands were the main body of grassland overload. The smaller the grassland management area, the higher the stocking rate. There was also a positive correlation between forage expenditure and stocking rate. Both typical steppe area and desert steppe area showed that the short-term energy supply of grassland in summer was greater than the energy demand of livestock, and met the good growth condition of livestock. The winter was cold and long, and the energy intake of the livestock was low. The energy shortage during the lambing period in January was as high as 10.5 MJ/SE·d in typical steppe area, and that was as high as 9.5 MJ/SE·d in desert steppe area in the same duration. In conclusion, appropriately adjusting the stocking rate is conducive to the improvement of grassland comprehensive production capacity and the economic income of family rangelands in Siziwang Banner.

In this study, a climate suitability evaluative test on 16 introduced alfalfa （Medicago sativa L.） varieties was conducted in Shebotu Town of Tongliao City of Inner Mongolia. The production performance, yield, and nutritional quality of the tested alfalfa varieties were determined, and the membership function method was used to comprehensively evaluate the indicators of production performance and nutritional quality. The results showed that, among the 16 tested alfalfa varieties, the varieties such as Dryland, Gongnong No.1, Jinhuanghou, and Aohan had better comprehensive performance and were suitable for planting in Tongliao area.

Sainfoin （Onobrychis viciifolia） is a perennial forage legume with good palatability, strong nitrogen fixation ability, abundant nutrition and rich condensed tannins. Its unique antiparasitic activity not only has a good control effect on animal and plant parasitic diseases, but also plays obvious roles in improving animal production performance and preventing the occurrence of other diseases. Sainfoin is an important forage species for the sustainable development of modern agriculture and animal husbandry, and has broad application prospects. A detailed review of the research progress in antiparasitic activity of sainfoin is provided in this paper, in hoping to provide references for the investigations on sainfoin.

In order to determine the value of cytological examination in clinical diagnosis of skin mastocytoma in canine, the diagnosis for two clinical cases of canine skin mastocytoma was carried out by combinative use of cytological and histopathological examinations. The cytological examination results were consistent with histopathological examination results. It is indicated that cytological examination has certain value in clinical diagnosis of skin mastocytoma in canine, and may provide valuable information on characteristic and differentiation degree of tumor. Therefore, cytological examination can serve as a new assisted diagnostic method for this disease.

In order to understand the development status of veterinary education in colleges and universities in China and accurately grasp the basic data of undergraduate education in training institutes of veterinary medicine in China, a survey of veterinary education in training institutes in China was conducted in year 2014 and year 2017. Essential data on the basic situation, training plans, teaching staff and school-running conditions of the training institutes were obtained. According to this, the database of undergraduate education in training institutes in veterinary colleges and universities in China was constructed. Based on this database, the current situation of veterinary education in China was analyzed.

On the basis of analyzing the problems existing in the talent cultivation of animal science specialty, relying on the ′real scene + virtual simulation′ innovative teaching resource platform, we explored a trinity of talent cultivation model of ′teaching, scientific research, and social service′ in animal science specialty. This teaching model moves the modern production scenes into the classroom, creates a realistic learning environment, inspires the undergraduates′ subjective initiative, and improves their practical abilities as well as innovation and entrepreneurship capabilities.

Professional certification is one of the means to guarantee the quality of higher education. Combining with the opportunity of professional certification of the veterinary medicine specialty of Yunnan Agricultural University in year 2018, this paper analyzes and discusses the talent training objectives of veterinary medicine specialty in Yunnan Agricultural University from the aspects of the positioning of training objectives, evaluation mechanism and the expected career development of the graduates, so as to take a series of improvement measures in the future revision process of training objectives and better adaptation to the talent training needs of veterinary medicine specialty in the new era.

Animal production is an application-oriented discipline with high practicality. The task of animal production teaching is to make undergraduates obtain new technologies and methods in modern livestock and poultry breeding, adapt to the requirement of the industry, and have the basic skills of serving enterprises. However, the existing teaching model in agricultural universities and colleges is hard to realize the above goals, and it is normal that the undergraduates′ learning enthusiasm can not be fully motivated in the classroom teaching. To train high-quality talents in animal husbandry who meet the social needs, the current curriculums are imperative to be reformed and innovated. Taking Cattle Breeding as an example, this paper elaborates the ideas and methods of the teaching reform for animal production curriculums from the aspects of optimizing classroom teaching contents, innovating teaching model, strengthening practical teaching, and improving assessment methods.