In order to reveal the coding characteristics and the secondary structure of pyruvate dehydrogenase kinase 4 （PDK4） gene in horse, the gene sequence of horse PDK4 was analyzed by using bioinformatical software. The results showed that in the CDS region of horse PDK4, the most frequently observed codons were AUU, AUG and GAU （14 times）, accounting for 34‰ of all the codons （413）. The minimum RSCU value （0） was found in UGC codon which was not involved in the coding region, the maximum RSCU value （2.22） was observed in the ACA codon, and the RSCU value of the five codons of CAU, CAC, CGA, AAA and AAG was 1, indicating no codon usage bias was found in these codons. A total of 412 amino acids were translated in the CDS region of horse PDK4, with the highest proportion of leucine and the lowest proportion of tryptophan. The complicated secondary structure of the horse PDK4 protein was dominated by coils, and β-strands as well as α-helices were complementary. The distribution of hydrophilic amino acids in horse PDK4 protein was more frequently observed than that of the hydrophobic amino acids, and the overall hydrophobicity of PDK4 was poor. The predicted isoelectric point of PDK4 was 6.64.

[Objective] To investigate the effects of dietary supplementation of Morinda officinalis How polysaccharides （MOP） on production performance, tibia index, tibial content of calcium ,phosphorus and ash, and serum electrolytes level in broilers with tibial dyschondroplasia （TD） induced by thiram. [Method] A total of 120 1-day-old healthy AA broilers were randomly divided into 3 groups with 4 replicates in each group and 10 broilers in each replicate. The broilers served as control （CON group） were fed with basal diet; the broilers used to establish TD model induced by thiram （TD group） were fed with basal diet at the initial period of the experiment, and then received dietary supplementation of 100 mg/kg thiram from the 4^th to 7^th day of the experiment; after receiving the same treatment with TD group, the broilers in MOP group were fed with basal diet supplemented with 400 mg/kg MOP from the 7^th to 15^th day of the experiment. [Result] Compared with the CON group, during the first 7 days of the experiment, the average feed intake and average daily gain of TD group was decreased significantly （P<0.05）, and the feed to gain ratio was increased （P>0.05）; in TD group, the tibial growth plate width and coefficient of growth plate width was increased significantly （P<0.05）, the tibial weight, length and ash content were decreased significantly （P<0.05）, and the tibial weight index was reduced （P>0.05） on the 7^th, 11^th and 15^th day of the experiment, in addition, the appearance of serum electrolyte disorder was also observed; compared with TD group, the MOP group had decreased feed to gain ratio （P>0.05）, significantly （P<0.05） decreased tibial growth plate width and coefficient of growth plate width, and significantly （P<0.05） increased tibial weight, length and weight index on the 11^th and 15^th day of the experiment; the tibial ash content of MOP group was increased significantly （P<0.05） on the 11^th day of the experiment; with the extension of the experimental period, the serum electrolytes level of the MOP group tended to balance. [Conclusion] Dietary supplementation of MOP can effectively alleviate and ameliorate the TD associated symptoms of broilers induced by thiram.

The objective of this study was to establish an ultra performance liquid chromatography-tandem mass spectrometry method for the determination of various quinolones residues in chicken blood samples. The samples were extracted with acetonitrile solution and were separated by Waters Acquity UPLC system with a BEH C₁₈ column. The used mobile phases were methanol and 0.1% formic acid aqueous solution in gradient elution. The electrospray was operated in the positive ionization mode, and the compounds were identified by MRM mode. Methodological identification showed that the linear relationship, recovery and precision of the established method met the requirements. A method for simultaneous determination of various quinolones residues in chicken blood samples by ultra performance liquid chromatography-tandem mass spectrometry was successfully established, and qualitative and quantitative analysis of 12 quinolones residues was achieved simultaneously.

Abstract：The purposes of this study were to elucidate the underlying mechanism responsible for the impact of fibroblast growth factor 21 （FGF21） on AMPK phosphorylation regulatory factors, and to clarify the effect of FGF21 on lipid droplet metabolism mediated by high NEFA in mouse hepatocytes. The AML12 mouse hepatocytes were received the treatment of NEFA addition and （or） FGF21 gene silencing; after that, the mRNA expression levels of FGF21, hepatokinase B1 （LKB1）, transforming growth factor β-activated kinase 1 （TAK1）, and calcium/calmodulin-dependent protein kinase kinase（CaMKK） of the mouse hepatocytes were assessed by using fluorescence quantitative PCR assay; the level of hepatic lipid deposition was detected by oil red O staining. The results showed that silencing of FGF21 gene significantly （P<; 0.05） decreased the mRNA expression level of LKB1, but had no significant effect on the mRNA expression level of TAK1 and CaMKK （P>; 0.05）. Furthermore, the level of lipid deposition in hepatocytes was significantly （P<; 0.05） elevated after silencing of FGF21 gene under high NEFA. In conclusion, FGF 21 may reduce the lipid deposition in mouse hepatocytes under high NEFA by activating AMPK signaling pathway via inducing LKB1.

[Objective] To compare the disinfection effects of hydrogen peroxide and formaldehyde on the interior surface, mesa and air of the breeding room of barrier SPF rats and mice, and to select effective disinfectants. [Method] The disinfection effects of hydrogen peroxide and formaldehyde by fumigation on reproductive chambers of SPF rats and mice were observed via air falling bacteria detection method and swab method. [Result] After fumigation with hydrogen peroxide and formaldehyde, the bacteria in the air of SPF rats breeding room and mice breeding room were detected. The sterilization rates of hydrogen peroxide and formaldehyde in the air of rats breeding room and mice breeding room were 100%, 97.5% and 100%, 100%, respectively. The bacterial colonies on the walls, floors and cage surfaces were detected for peroxidation. The bactericidal rates of hydrogen peroxide and formaldehyde on the walls, floors and cage surfaces of rats reproductive chambers were 100%, 99%, 100% and 95%, 100%, 99%, respectively, and those of mice reproductive chambers were all 100%. [Conclusion] Steam disinfection with hydrogen peroxide is an ideal disinfection method, which can effectively control the microorganisms in the breeding room of SPF rats and mice and has high safety and obvious disinfection effect.

The purpose of this study was to investigate the effects of condensed tannin derived from Caragana korshinskii in diets on ruminal fermentation parameters in sheep. A total of 15 healthy Dorper and Mongolian crossbred wether weighing around 40 kg were selected and randomly divided into 3 groups according to their body weight. The control group （n=5） contained no tannins in the diet; the test groupⅠ（n=5） and Ⅱ （n=5） received the diet containing 2% and 4% of tannin, respectively. The ruminal fluid of each group was collected before morning feeding （0 h） and 3 h, 6 h and 9 h after morning feeding, respectively, and the rumen internal environment indicators of the experimental wether, including pH value, ammonia nitrogen （NH₃-N） concentration and bacterial protein （BCP） level, were measured and statistically compared. The results showed that feeding the diets containing 2% （test groupⅠ） and 4% （test groupⅡ） of tannin had no significant （P>0.05） effect on ruminal pH value; the wether had significantly （P<0.05) lower ruminal NH₃-N concentration 3 h and 6 h after receiving the diets containing 2% （test groupⅠ） or 4% （test groupⅡ） of tannin; the ruminal BCP level of the wether was significantly （P<0.05） elevated 6 h and 9 h after receiving the diets containing 2% （test groupⅠ） or 4% （test groupⅡ） of tannin. The combined data suggested that while dietary supplementation of 2% or 4% of tannin derived from Caragana korshinskii had no impact on ruminal pH value in wether, it was able to reduce the ruminal NH₃-N concentration and ruminal BCP level.

The study was conducted to investigate the effects of replacing antibiotics using different dosages of organics acidifier on growth performance of weaning piglets. A total of 144 Duroc×Landrace×Yorkshire crossbred weaning piglets with similar initial average body weight [（8.70±0.20）kg] and days of age were randomly divided into 4 groups, including control group and experimental groups of 1, 2 and 3. There were 4 repeats in each group and 9 piglets in each repeat. The control group was fed with basal diet,the experimental group 1 fed the basal diet supplemented with 25 mg/kg duomycin and 50 mg/kg quinocetone, and the experimental groups of 2 and 3 received dietary supplementation of 0.4% and 0.7% organic acidifier composed of formic acid, lactic acid, citric acid and fumaric acid, respectively. The experimental period lasted for 14 days. The results showed that compared to the control group, the daily gain of the experimental groups of 1, 2 and 3 were significantly （P<0.05） elevated by 20.60%, 7.90% and 15.30%, respectively; the feed to gain ratio of the experimental groups of 1, 2 and 3 were significantly （P<0.05） reduced by 13.20%, 7.60% and 13.35%, respectively;the diarrhea rate of the experimental groups of 1, 2 and 3 were 16.11%, 11.11% and 15.91% lower than that of the control group, and significant （P<0.05） differences were observed; there were no significant （P>0.05） difference in average daily feed intake between the control group and the three experimental groups; the experimental group 3 had the similar effect on improving daily gain and feed to gain ratio of the weaning piglets with experimental group 1. In conclusion, dietary supplementation of organic acidifier improved the growth performance of weaning piglets, and the higher dosage of organic acidifier had the similar effect with the combinative use of duomycin and quinocetone.

In this study, in vitro gas production technique was used to investigate the effect of different levels of disodium fumarate on rumen fermentation in sheep with a one-factor completely randomized design. The soluble starch and cellulose were used as carbon sources, tryptone was used as nitrogen source. Disodium fumarate accounting for 1.0%, 2.0% and 3.0% of the dry matter of fermentation substrate were added in experimental groups 1, 2 and 3, respectively. The control group received no addition of disodium fumarate. The results showed that compared with the control group, adding 1% of disodium fumarate （experimental group 1） could significantly （P<0.05） improve the output of total volatile fatty acids, acetic acid, propionic acid and butyric acid, in vitro gas production, and dry matter degradation rate; the significantly （P<0.05） increased output of total volatile fatty acids, acetic acid, propionic acid and butyric acid as well as significantly （P<0.05） elevated dry matter degradation rate were observed in experimental group 2 compared to the control group; there was no significant （P>0.05） differences in ammonia nitrogen concentration, total volatile fatty acid and acetic acid output, gas production and dry matter degradation rate between experimental group 3 and control group, but experimental group 3 had significantly （P<0.05） increased propionic acid production. In conclusion, adding 1% or 2% fumarate disodium can significantly improve the rumen fermentation performance of sheep, but adding 3% fumarate disodium exhibited an inhibiting effect on rumen fermentation capacity to a certain extent.

Due to the seasonal variations of forage yield and nutritive value in desert grassland, the lack of nutrimental intake before mating period always leads to the poor fertility of ewes. To assess the short-term nutritional supplementary feeding on reproductive performance of freely grazed Gobi short-tailed ewes, an optimized dietary nutrition collocation scheme with high-nutrition feed were provided for the ewes 25 days before mating to improve the nutritional supplementation level in a short period of time. The results showed that the lambing rate of the ewes in the two experimental groups was 6.40% and 19.69% higher than that of the control group after short-term high-concentration supplementation, and the twin lambing rate was 6.92% and 10.20% higher than that of the control group. In this short-term nutritional supplementary feeding mode, the lambing performance of the ewes are improved to a certain extent, and the economic income of the herdsmen′s sheep raising is improved.

[Objective] Based on the theory of traditional Chinese veterinary medicine, a traditional Chinese medicine compound preparation Buzhong Yiqi powder was used to assess its roles in prenatal conditioning for sows in the late pregnancy by investigating its effect on production performance of sows, in hoping to province scientific basis for the application of safe, green and organic feed additives of traditional Chinese medicine compound. [Method] A total of 50 sows with similar expected delivery dates were randomly divided into 2 groups with 25 heads of sows in each group. The control group was fed with the basal diet, and the experimental group was fed with the basal diet supplemented with 1.5% （45 g per day per sow） Buzhong Yiqi powder until the date of delivery. After delivery, the number of litters, live litters, healthy litters, stillbirths, weak litters and mummified fetuses were recorded for each group, and the presence of abortion was observed. Incidence of diarrhea and death of the piglets were recorded after weaning at 23 days of age. [Results]①In the experimental group, there was one sow had fever and anorexia before delivery, while there were 5 sows showed the same symptoms in the control group; ②After delivery, a total of 227 and 254 piglets were obtained in the control group and the experimental group, respectively, and there were 12 and 9 stillbirths in the control group and the experimental group, respectively; ③ The average size of live litters in the control group and the experimental group was 9.08 and 10.16, respectively; ④ There were 74 and 10 piglets showed the clinical symptoms of diarrhea in the control group and the experimental group, respectively, with the diarrhea rate of 32.6% and 3.9%, respectively; ⑤After weaning, the average size of healthy litters in the control group and the experimental group was 7.16 and 9.28, respectively; ⑥There were 179 and 232 survived piglets in the control group and the experimental group, respectively, with the survival rate of 78.9% and 91.3%, respectively. [Conclusion] ①Prenatal conditioning of sows using Buzhong Yiqi powder can effectively prevent the occurrence of diarrhea in suckling piglets.②Dietary supplementation of Buzhong Yiqi powder during pregnancy

In order to exploit and utilize the Amaranthaceae forage resources, a total of 16 Amaranthaceae forage samples collected from Chongqing were used as experimental materials in this study, and the phenological period, agronomic traits and production performance of the tested samples were determined and compared. Furthermore, principal component analysis and cluster analysis were used to evaluate the comprehensive quality of the 16 Amaranthaceae forage. The results showed that among the 16 materials, the No.15 sample （serial number: 2015502019, name：′Feitianxian′） had the highest comprehensive score and the best performance, followed by No.3 sample （serial number: xky201703002, name：Amaranthus hypochondriacus）, No.5 sample （serial number: 2016501818, name: Amaranthus tricolor) and No.9 sample （serial number: 2015502704, name：′Tianxunmi′）. In conclusion, these four materials have the value for further breeding, development and utilization.

Stipa klemenzii steppe is the main vegetation type in north piedmont of Yinshan Mountain in Inner Mongolia. It is an important ecological security barrier and animal husbandry base. Based on the primary plots data obtained from fieldworks during the growing seasons from 2012 to 2017 as well as some earlier records, we studied the community characteristics and classifications of Stipa klemenzii steppe in north piedmont of Yinshan Mountain. The results showed that the quantitative characters of the community of Stipa Klemenzii steppe had an obvious fluctuated. The average species number, height, total coverage, biomass dry weight, diversity index （Simpson and Shannon-wiener index）, average richness index and average evenness index were separately 9 species/m², 10 cm, （12±5）%, （57±33） g/m², around 0.7, 2.09 and 0.55. A total of 79 species of seed plants, belonging to 21 families and 51 genera, were obseved in Stipa Klemenzii steppe, among which the families with the most species were Gramineae, Leguminosae and Compositae. Species with the occurrence frequency exceeding 60% included Stipa Klemenzii, Convolvulus ammannii, Cleistogenes songorica, Allium tenuissimum and Astragalus galactites. As for the ecological type of water, there were 57 species of xerophytes and typical xerophytes, accounting for 72% of the total species. In addition, perennial forbs as well as annual and biennial species were the two dominant life forms, covering 48% and 24% of the species, respectively. East Palaeo-North areal-type and middle Asian areal-type were the two major floristic elements, containing 33% and 32% of the species, respectively. Based on the life forms and dominances of the species within the community, Stipa Klemenzii steppe could be classified into 3 formations, 7 association groups and 13 associations. Convolvulus ammannii and Allium polyrhizum formation were the degraded types of Stipa klemenzii. The communities with degenerated indicator species as sub dominant species and constructive species were widely distributed in north piedmont of Yinshan Mountain, reflecting that the degradation of Stipa Klemenzii steppe was still serious at present stage.

This study analyzed the changing characteristics of plant community in mowed grassland of slightly degraded meadow steppe before and after spraying the multi-functional fertilizer, including the height, coverage and above-ground biomass of grasses. The results showed that the application of foliar fertilizer had minor effect on the coverage of grasses in the mowed grassland, but it could significantly increase the height and above-ground biomass of the grasses. The grasses height of the grassland receiving 2-year-long fertilization was averagely 7.32 cm higher than that of the control, and its above-ground biomass of the grasses had an increase of 39.42 kg/667 m².

Equus are seasonal single-born animals. The duration from the estrous appearance to ovulation lasts for 3 to 13 days in mares or jennets. This physiological characteristic greatly affects their reproductive rate. hCG, as a LH analogue, is widely used in the study of follicular development and ovulation in Equus animals, which is not regulated by sex hormones feedback mechanism. This paper reviews the research progress on ovulation promoted by hCG in Equus animals from the following five aspects: the role of sex hormones in mammalian follicular development, main follicular wave and the ovulation of the dominant follicle induced by LH in Equus animals, the impacts of exogenous hormone on follicular development in Equus animals, structure and function of hCG, the application of hCG in prolonging the luteal phase in mares and in superovulation in Equus animals.

Active immunization with GnRH analogue vaccines can achieve similar effects with surgical castration in animals, avoiding the affects of surgical castration on animal health. Antigens, adjuvants, immunization times, immunization doses, and immunization time point of GnRH analogue vaccines all have effects on their immune response. Immunization with GnRH analogue vaccines in animals often requires potent adjuvants and multiple boosts to overcome differences in individual responses.

In order to investigate the influence of adding glutathione （GSH） in frozen diluent on cryopreservation effect of canine semen, the seminal samples were collected from 5 hybrid dogs by massage method. After centrifugation to remove the seminal plasma, 0.5, 1.0, 1.5, 2.0 and 2.5 mmol/L of GSH was supplemented in the frozen diluent, respectively. All of the above samples with volume of 0.25 mL containing different concentrations of GSH were prepared for cryopreservation. The seminal samples without addition of GSH was used as a control group. After thawing, the samples were incubated for 10 hours in air containing 5% CO₂ at 37 ℃ with relative saturated humidity. The sperm motility of the samples was determined at 0, 2, 4, 6, 8, 10 h after incubation, respectively. The results showed that at 0 h after freezing and thawing, the sperm motility of the 0.5 and 1.0 mmol/L GSH treatment groups was 0.36 and 0.38, respectively, which were both significantly （P<0.05） higher than those of the control group and 2.0 and 2.5 mmol/L GSH treatment groups, and no significant difference （P>0.05） were observed between them; the highest （85.10%） sperm acrosome integrity rate and the lowest （23.00%） sperm deformity rate were simultaneously observed in the 1.0 mmol/L GSH treatment group, and they were significantly （P<0.05） higher and significantly （P<0.05） lower than those of the control group, respectively. After incubation for 2 and 4 hours after freezing and thawing, the sperm motility of the 0.5 and 1.0 mmol/L GSH treatment groups was relatively higher, and that of the 0.5 mmol/L GSH treatment group after in vitro incubation for 4 hours still reached up to 0.30; after in vitro incubation for 6 hours, the highest sperm motility was observed in the 1.0 mmol/L GSH treatment group, which was significantly （P<0.05） higher than those of the control group and 2.0 and 2.5 mmol/L GSH treatment groups; after in vitro incubation for 8 hours, the sperm motility of all GSH treatment groups was significantly （P<0.05） higher than that of the control group; after in vitro incubation for 10 hours, the sperm motility of each GSH treatment group was all decreased compared with other incubation time points, and there was no sperm with linear motion in the control group. In summary, the addition of 0.5-1.0 mmol/L GSH in freezing solution of canine semen can significantly improve the sperm quality and in vitro survival time after freezing and thawing.

In this study, the mutton consumption status in Zhangjiakou City of Hebei Province was investigated by using questionnaire survey method to understand the mutton consumption of the main sheep breeding areas. The results showed that the mutton consumption in Zhangjiakou City accounted for 23.93% of the total meat consumption; the respondents who considered the safety and quality of mutton accounted for 52%, which was the most important factor for consumers to make purchasing decisions; the respondents whose consumption decision impacted by the factor of price accounted for 23%, and those who considered the income, age and season when made the purchasing decisions accounted for 25% in total; the consumers preferred the mutton produced from the sheep raised by free grazing way, and most of them chose to purchase the fresh mutton from mutton exclusive shops; the popular mutton product types mainly included mutton rolls and mutton shashlik. This study tries to link the sheep breeding with mutton consumption, and analyzes the characteristics of mutton consumption in the farming-pastoral zone in Hebei Province, in hoping to provide references for guiding the breeding direction of the mutton sheep industry.

In order to provide better guide for the construction of the high-quality fattening lambs production system in Ulanqab City, and to compare the breeding economic benefits between Dorper × Mongolian × Suffolk ternary hybrid lambs and local Mongolian sheep lambs under the same feeding and management conditions, a test was conducted to assess the meat production performance of the crossbred lambs. The weight of the crossbred lambs and local Mongolian sheep lambs in different growth period were determined and compared. The results showed that under the same natural environment and feeding and management conditions, the crossbred lambs had higher average birth weight, weaned weight, 5-month-old slaughter weight and 5-month-old average daily gain compared to the local Mongolian sheep lambs. It was demonstrated that promoting the production system construction of Dorper × Mongolian × Suffolk ternary hybrid lambs is one of the effective ways to realize the ecological and efficient breeding in grassland of pastoral areas and to improve quality and efficiency of sheep breeding for farmers and herdsmen.

This study aimed to obtain the bacterial strains that could effectively degrade the cellulose in beef cattle manure. The cellulose-degrading bacteria were isolated from cattle feces and their natural compost samples by using sodium carboxymethyl cellulose as carbon source. Subsequently, the isolated strains were morphologically and molecularly identified. The cellulose-Congo red medium and filter paper degradation test were used to further assess the cellulose-degrading ability of the isolates. The results showed that a total of 32 cellulose-degrading isolates were obtained, and 4 of them （designated as XQ-1, XQ-2, XQ-3 and XQ-4, respectively） had hydrolyzed circle in Congo red medium and had a certain ability to degrade the filter paper. The 16S rDNA sequencing identification demonstrated that the 4 strains were Escherichia coli, Serratia marcescens, Providencia rettgeri and Escherichia fergusonii, respectively.

Course assessment was a means to test students′ mastery of the course knowledge and their ability to use it, and also a standard to measure and evaluate the teaching effect. According to the requirements of professional personnel training, the purpose of improving the assessment method of Cattle Production was to test the learning effect of students. This paper summarized and analyzed the problems existing in the course assessment of Cattle Production, and put forward the idea of improving the course assessment for the purpose of promoting students′ active learning and improving students′ comprehensive quality. This paper summarized a series of specific methods of course assessment to improve the quality of teaching.

Veterinary Lemology, as one of the main courses of veterinary medicine specialty,is an important link between graduates of veterinary medicine specialty and social needs. According to the changes of the epidemic and control characteristics of animal infectious diseases under the new situation, this paper discusses the direction and measures of teaching reform of Veterinary Lemology in veterinary medicine specialty in colleges and universities, aiming to stimulate students′ interest in learning,improve teaching effect,enhance students′ professional theory and practical skills and cultivate talents in veterinary medicine that meet the needs of industry.

Abstract：In order to identify the current situation of the cognition of equine science education in undergraduates of agricultural universities, a survey of questionnaire was conducted in two agricultural universities. It showed that most of the students had experience with horses, and most in the tourist attractions and riding clubs. Most students could recognize the sports and entertainment functions of horses in society. Some students still had vague cognition of modern horse industry influenced by source of students and the courses established related to horses. It is necessary to strengthen the training of knowledge and skills through the establishment of related majors of equine science. In addition, to maintain the sustainable and healthy development of China horse industry, the increased media propaganda and social promotion should be made, and the cognition of equine science education of students should be improved.

In order to explore the application effect of micro-course in theoretical teaching of Anatomy of Domestic Animals, two teaching classes of veterinary medicine specialty were randomly selected as the research objects. The experimental group were taught with the pre-class, classroom and after-school application of the micro-course, and the traditional teaching mode were adopted in the control group. The results showed that the test scores of the experimental group were significantly （P<0.05） higher than those of the control group. However, after the introduction of the micro-course teaching mode, the test scores of the control group were significantly （P<0.05） improved, and there was no significant difference in the test scores between the control group and the experimental group （P>0.05）. It was concluded that the introduction of micro-course in the teaching process of Anatomy of Domestic Animals not only improved the quality of teaching but also stimulated students′learning interest and enthusiasm in this curriculum, changing from passive learning into active learning.

The practical teaching of Animal Epidemic Disease Prevention and Control Technology is one of the important contents of undergraduate practical teaching for veterinary medicine specialty. Based on the improvement of the previous teaching methods, a series of reforms on teaching modes, teaching programs and assessment methods were carried out by employing the multi-form practical teaching and assessing the effect of practical teaching with comprehensive evaluation, in combined with the learning feedback mechanism to improve the implementing effect, in hoping to provide references for the adjustment and implementation of practical teaching.

The knowledge of Veterinary Virology is trivial and abstract, and the difficulty to understanding the content of this course always results in undergraduates′ deficient enthusiasm for learning. The expression way of Veterinary Virology under the traditional teaching mode is single and limited, and the corresponding teaching quality and teaching effect are unsatisfied. Integrating virtual simulation technology into Veterinary Virology teaching can improve the teaching mode, stimulate undergraduates′ interest in learning, enhancing learning efficiency and experimental skills, and help to cultivate high-quality veterinary talents with strong innovative and practical ability.

Actinobacillus strains are symbiotic bacteria colonizing the mucous membrane of animals. They can invade the body when wounds in oral mucosa or skin appear and then result in actinobacillosis. This disease is characterized by sporadic epidemic. In addition, improper feeding and management may also associate with the emergence of this disease, which always bring great losses for the livestock breeding industry. In this paper, the clinical symptoms, pathological changes, laboratory examination and differential diagnosis of a clinical case of lamb actinobacillosis emerged in a sheep farm in spring of 2019 in Hohhot were introduced in detail. Furthermore, the corresponding prevention and control measures were put forward for veterinary personnel and sheep farmers.

This paper introduces the etiological characteristics of porcine epidemic diarrhea virus （PEDV）, and proposes effective measures and key technologies for prevention and control of porcine epidemic diarrhea （PED）, in hoping to provide references for the scientific prevention of the emerging and prevalence of PED in swine farms in cold season.