[Objective] To explore the optimal preparation method of recombinant Brucella outer membrane protein Omp19, to evaluate its immunogenicity in experimental animals, and to lay the foundation for the follow-up pilot-scale study. [Method] The recombinant Omp19 protein was expressed by prokaryotic induction using the shake flask culture method, and the effects of different culture mediums, IPTG concentrations, induction temperatures, induction durations, and bacterial densities on protein expression were evaluated and optimized. The recombinant Omp19 protein was expressed and purified by cation exchange chromatography, hydrophobic chromatography, and anion exchange chromatography methods. The purity of the recombinant Omp19 protein was characterized using SDS-PAGE and SEC-HPLC methods. The immunogenicity of the recombinant Omp19 protein was evaluated by animal experiment. [Result] Shake flask culture test showed that the better expression conditions of recombinant Brucella Omp19 protein were as followed: using the LB medium culture and inducing at OD_{600 nm} of 0.6 ~ 1.0 of bacterial densities with 0.5 mmol/L IPTG at 28 ℃ for 5 h. The highly pure recombinant Omp19 protein was obtained after the three steps of purification. Immunogenicity studies revealed that the recombinant Omp19 protein could effectively stimulate the production of specific antibodies when formulated with adjuvants in BALB/c mice. [Conclusion] This research optimized the preparation method of recombinant Brucella Omp19, evaluated its immunogenicity in mice, and provided the experimental basis for recombinant Brucella vaccine development.

[Objective] To assess the safety of recombinant bovine granulocyte colony stimulating factor （rbG-CSF）, so as to set the groundwork for its future clinical trials. [Method] Using rbG-CSF recombinant Escherichia coli, rbG-CSF was obtained after fermentation and purification. The target protein was identified by SDS-PAGE, and its concentration was determined by BCA method. In acute toxicity test, a total of 112 healthy Kunming mice were divided into eight groups, each with half males and half females. The eight groups were then evenly divided into intramuscular injection groups and intraperitoneal injection groups, with one control group and three rbG-CSF treatment groups each. The treatment groups intramuscularly or intraperitoneally received 150, 75, and 37.5 μg per mice of rbG-CSF, while the corresponding control groups both received a saline injection. Following administration, the mice were weighed every 3 days for consecutive 14 days. On the 14^th day post injection, the liver, spleen, kidney, and reproductive organs of mice in each group were dissected for organ coefficient assessment and pathological section observation. In chronic toxicity test, a total of 160 healthy Kunming mice were used. The grouping protocol was identical to that of acute toxicity test. The rbG-CSF were intramuscularly or intraperitoneally administrated once a week with dosages of 15, 10, and 5 μg per mice for consecutive 12 weeks. The mice were weighed on the 6^th day post injection weekly. The mice were dissected 7 days after the injection on the 12^th week. The subsequent treatment approaches were identical to those used in acute toxicity test. [Result] The target protein rbG-CSF was successfully purified and was found to be 21.5 kDa identified by SDS-PAGE, which was in line with the anticipating size. The concentration of the target protein was 302.19 μg /mL, which met the concentration requirement for the subsequent safety test. In both acute and chronic toxicity tests, one-way ANOVA analysis （SPSS 20.0） revealed that there were no significant differences in body weight and organ coefficient between rbG-CSF intramuscular or intraperitoneal injection groups and corresponding control groups. No macroscopic and histopathological changes were observed in mice received rbG-CSF injection. [Conclusion] The developed methods for purifying and identifying rbG-CSF are feasible. At the concentrations observed in this study, rbG-CSF has no organic damage in mice.

[Objective] To clone the coding region sequence （CDS） of CAP2 gene in Qinchuan bovine, and to characterize the expression profiling of this gene in various tissues and during the primary adipocyte differentiation. [Method] The CDS region of CAP2 gene in Qinchuan bovine was amplified by RT-PCR assay, and the CAP2 protein was analyzed using online bioinformatical tools such as ProtPram, TMpred, and ProtFun 2.1 Server. The gene expression levels of PPARγ and FABP4 were detected using qPCR assay and oil red O staining method to construct a bovine primary adipocyte induced differentiation system. Moreover, the expression levels of CAP2 gene in seven tissues （heart, liver, spleen, lung, kidney, muscle, and back fat） as well as during the differentiation process of primary adipocyte （0-10 days） in Qinchuan bovine were assessed using qPCR assay. [Result] The CDS region of CAP2 gene in Qinchuan bovine was 1 461 bp and encoded 486 amino acids. Its amino acid sequence mainly composed of random coil and α-helix. Extremely significantly （P<0.01） higher expression level of CAP2 gene was observed in back fat in comparison to the other tested tissues. During the differentiation process of primary adipocyte, the expression levels of PPARγ and FABP4 genes increased gradually and peaked on day 10, which were extremely significantly （P<0.01） higher compared to day 0. The induced differentiation group of primary adipocyte had a much larger lipid droplet accumulation than the control group. Furthermore, the expression level of CAP2 gene increased gradually with the prolongation of induced differentiation duration, and peaked on day 10 as well, which were extremely significantly （P<0.001） higher compared to day 0. [Conclusion] The 1 461 bp full-length CDS of CAP2 gene in Qinchuan bovine has been successfully cloned. The CAP2 gene is highly expressed in adipose tissue and may involves in adipogenesis and differentiation. As a result, the CAP2 gene is assumed to be a transcription factor that promotes adipogenic differentiation, plays a key role in regulating the status of bovine adipocyte, and could be a candidate gene associated with meat quality trait of Qinchuan bovine. These findings provide preliminary information for further revealing the function of bovine CAP2 gene.

[Objective] To assess the mRNA and protein expression of pik3r3, Akt and mapk3 genes in sheep oviduct epithelial cells after stimulation with estradiol. [Method] The mRNA and protein expression levels of pik3r3, Akt and mapk3 genes in oviduct epithelial cells within five passages were detected by qPCR and Western blot respectively after incubation with 10-8 mol/L estradiol （equivalent amount of medium instead of estradiol were used as the control group） for 0, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, and 5.0 h. [Result] After adding 10-8 mol/L estradiol to sheep oviduct epithelial cells, the mRNA and protein expression levels of pik3r3, Akt and mapk3 genes increased first and then reduced as the incubation time progressed. The mRNA expression （P<0.01） and protein expression （P<0.05） of the pik3r3 gene peaked after 1.5 h treatment with estradiol, whereas the mRNA expression （P<0.01） and protein expression （P<0.05） of the Akt and mapk3 genes peaked at 2.5 h treatment with estradiol. The mRNA expression of pik3r3, Akt and mapk3 genes all significantly （P<0.05） increased after 3.0 h of estradiol treatment. [Conclusion] Estradiol regulates the expression of pik3r3, Akt and mapk3 genes in sheep oviduct epithelial cells. High levels of estrogen facilitate the expression of pik3r3, Akt and mapk3 genes, which is linked to the innate immune defence in the reproductive tract, and may improve the autoimmune response via this mechanism.

[Objective] To investigate the effects of pre-drying treatment and supplementation of mixed preparations composed of molasses and Lactobacillus plantarum on nutritional components and fermentation quality of forage millet silage. [Method] The forage millet varieties of NO.106 and NO.107 harvested at the filling stage were used as materials. A two-factor （water content × additive） completely randomized designed trail was carried out. For both of the millet varieties, the silage was prepared with fresh and pre-dried materials containing different water contents, respectively. The control groups （CK） had no addition of additive, while the experimental groups （ML） had a combined addition of 1% molasses and 0.2% Lactobacillus plantarum. Each treatment had three repeats and fermented for 45 days at room temperature （20-30 ℃）. The contents of dry matter, conventional nutritional components, lactic acid and volatile fatty acids as well as pH value of the unsealed silage were measured after fermentation. [Result] Pre-drying treatment extremely significantly （P<0.01） increased the dry matter content and pH value of the two forage millet silage. Furthermore, it significantly （P<0.05） increased the neutral detergent fiber content as well as extremely significantly （P<0.01） decreased the contents of lactic acid and acetic acid of NO.106 forage millet silage. The dry matter content in the pre-dried ML group of NO.106 forage millet silage was extremely significantly （P<0.01） higher than that in its corresponding CK group. The pH value in the fresh and pre-dried ML groups of both forage millet silage was extremely significantly （P<0.01） lower than that in their corresponding CK groups, while the lactic acid content was extremely significantly （P<0.01） higher. The acetic acid content in pre-dried ML groups of both forage millet silage was significantly （P<0.05） higher than that in their corresponding CK groups. [Conclusion] Although pre-drying treatment was conductive to retain the nutritional components in the forage millet silage, it had an inhibitory effect on silage fermentation. Addition of molasses and Lactobacillus plantarum had minor influence on nutritional components, but it stimulated the lactic acid fermentation, dramatically lowered pH value, and raised lactic acid/acetic acid value of the forage millet silage.

[Objective] To determine the optimal preparation conditions of ethanol extracts from Artemisia scoparia, a compositae plant. [Method] The extracts from Artemisia scoparia were prepared by the condensation tube reflux extraction method with ethanol as extraction solvent. A orthogonal test was designed by four factors （extraction temperature, ethanol concentration, solid-liquid ratio, and extraction time） with three levels respectively. The optimal preparation conditions were determined according to the yield of ethanol extracts. [Result] According to the analysis of variance and range R value, orders of the extraction effects of the four factors on yield of ethanol extracts of Artemisia scoparia was as follows, extraction temperature > ethanol concentration > extraction time>solid-liquid ratio. The influence of extraction temperature on yield of ethanol extracts was extremely significant （P<0.01）, revealing that it was the primary factor impacting the extraction effect. The ethanol concentration, solid-liquid ratio, and extraction time had no significant （P>0.05） effects on yield of ethanol extracts, demonstrating that they were the secondary variables impacting the extraction effect. The optimal preparation conditions of ethanol extracts from Artemisia scoparia were ethanol concentration at 65% with a 1∶7 solid-liquid ratio, and 3.0 h of extraction at 75 ℃. [Conclusion] This study determined the optimal preparation parameters for ethanol extracts from Artemisia scoparia under laboratory conditions, providing a reference for further research and application of extracts and bioactive components of Artemisia scoparia.

Reproductive performance is a significant economic trait of the sheep industry, as it directly determines to the cost and benefit of production. Low reproductive efficiency of sheep due to their seasonal reproductive characteristics is the fundamental barrier of high-efficient breeding in the sheep industry. The nutrient level of ewes has a direct impact on their reproductive performance in sheep farming. This paper summarizes the effects of nutrient level on the reproductive process of ewes, including estrus, ovulation, and pregnancy, as well as on the reproductive performance of ewes during non-reproductive seasons. Furthermore, the research progress on reproductive performance regulation of ewes by precision nutrition approach is reviewed, in hoping to provide a reference for further study on the mechanisms underlying the regulatory role of nutrient level in reproductive performance of ewes.

Probiotics are live bacterial agents that can colonize the gut of the host, maintain the intestinal microecological balance, and improve the host′s health. Probiotics have been shown to have a number of beneficial impacts on animals. With the increasing growth of the pet medical industry, owners are paying more and more attention to the health of their dogs and cats. By preserving the balance of intestinal microecology, probiotics are commonly added to pet food and nutritional supplements to prevent intestinal illnesses and boost intestinal immunity. This paper reviews the definition, varieties, and action mechanisms of probiotics, as well as the research progress on application of probiotics in dogs and cats, in hoping to serve as a reference for the development of probiotics in dogs and cats and their application in the pet medical industry.

Aflatoxins are mainly a class of highly toxic secondary fungal metabolites produced by Aspergillus flavus and Aspergillus parasiticus. Most grains and animal feeds around the world are polluted by aflatoxins, which poses a severe threat to animal health and the sustainable development of livestock and poultry breeding industry. Aflatoxin B₁（AFB₁） is a common and highly toxic mycotoxin. Excessive intake of AFB₁ has a series of toxic effects such as carcinogenesis, teratogenesis and immunosuppression. A large number of studies have confirmed that AFB₁ can seriously affect the growth, immune function and organ development of broiler chickens, and threaten the healthy development of poultry industry. Combined with the research reports in China and abroad, this paper summarizes the properties and toxicity of aflatoxins, and expounds the research progress on the toxic effects of AFB₁ on broiler chickens from the four aspects of intestinal dysfunction, immunosuppression, organ damage and genetic toxicity, which may provide a reference for further elucidating the molecular mechanism underlying the toxic effects of aflatoxins in broiler chickens and for mitigating their risk in broiler farming.

Prebiotic properties of functional oligosaccharides and sugar alcohols have sparked interest in food and nutrition research. As cecal starters, the functional oligosaccharides and sugar alcohols are not degraded by digestive enzymes in the small intestine, and then they enter the cecum to be fermented by microorganism to produce short-chain fatty acids, reduce the pH value in the intestinal lumen, and promote the proliferation of intestinal mucosal epithelial cells, to improve the absorption of minerals in the large intestine. This paper reviews the research progress on promoting effects and the related mechanisms of functional oligosaccharides and sugar alcohols on intestinal absorption of minerals in rats in recent years, in hoping to provide a reference for the application of functional oligosaccharides and sugar alcohols in food and feed production.

[Objective] To assess the genetic and evolutionary relationships between locally bred dairy goat varieties in China and those introduced abroad. [Method] Four domestic dairy goat breeds （Wendeng dairy goat, Guanzhong dairy goat, Laoshan dairy goat, and Ya′an dairy goat） in China and three introduced breeds （Alpine dairy goat, Toggenburg dairy goat, and Saanen dairy goat） from New Zealand were used as research subjects. Peripheral blood samples were collected from 33 individuals and the genomic DNA was extracted. The full-length of D-loop region of mitochondrial DNA （mtDNA） were amplified by PCR assay and then sequenced. The obtained sequences were subjected to bioinformatic analysis to uncover the genetic diversity and evolutionary relationship of various dairy goat breeds.[Result] The contents of A/T in the mtDNA D-loop region of 7 dairy goat breeds were higher than those of G/C. A total of 82 variable sites, 25 singleton variable sites, and 55 parsimony informative sites were found. The haplotype diversity （Hd） of the studied dairy goat breeds ranged from 0.905 to 1.000, and the nucleotide diversity （Pi） ranged from 0.001 51 to 0.013 32. There were 26 haplotypes in total, including 5 haplotypes each in Wendeng dairy goat and Saanen dairy goat, 4 haplotypes in Alpine dairy goat, 3 haplotypes each in Laoshan dairy goat, Toggenburg dairy goat, Guanzhong dairy goat, and Ya′an dairy goat. The ranges of average nucleotide diversity （K_XY）, nucleotide variation （D_XY）, genetic differentiation index （G_ST）, and genetic differentiation index （F_ST） were 6.400 00-38.450 00, 0.005 79-0.034 76, 0.000 00-0.186 05, and 0.231 56-0.971 52, respectively. According to the phylogenetic tree among different breeds, Wendeng dairy goat and Laoshan dairy goat were genetically clustered together into one branch. The genetic relation between Guanzhong dairy goat and three New Zealand dairy goat breeds was closer, proving that Guanzhong dairy goat was bred by hybridization of local breeds with foreign dairy goats. Ya′an dairy goat had the greatest genetic distance from the other breeds. [Conclusion] In Chinese dairy goats, there are two lineage origins with no evidence of population expansion. The locally bred dairy goats in China are highly genetically linked with foreign dairy goats. Wendeng dairy goat has closely genetic relationship with Laoshan dairy goat, and Ya′an dairy goat may have experienced regional isolation during the genetic evolution.

[Objective] To characterize the differences in milk yield and composition between Yili and Kazak lactating mares throughout various lactation months, so as to provide references for development and utilization of milk characteristics of Yili and Kazak mares. [Method] Twelve healthy Yili mares and twelve healthy Kazak mares of similar age, parity, and foal time were chosen at random. The milk yield of the two breeds of mares at 30, 60, and 90 days of lactation, representing for the first, second and third lactation months, respectively, was recorded under the same dietary nutrition and feeding management levels. Meanwhile, milk samples were collected to determine the milk somatic cell count, milk fat rate, milk protein rate, milk lactose rate, and milk total solid content of the two breeds of mares at different lactation times. [Result] At 30 days of lactation, higher （P>0.05） milk yield, extremely significantly （P<0.01） higher milk fat rate, and significantly （P<0.05） higher milk somatic cell count was observed in the Kazak mares in comparison to the Yili mares, and the other milk composition indexes were higher （P>0.05） in the Kazak mares as well. At 60 days of lactation, the Yili mares had extremely significantly （P<0.01） higher milk yield and milk lactose rate, higher（P>0.05） milk fat rate and milk protein rate, and lower （P>0.05） milk somatic cell count and milk total solid content than those of the Kazak mares. At 90 days of lactation, compared with the Kazak mares, the milk yield of the Yili mares was significantly （P<0.05） higher, the milk lactose rate and milk total solid content were extremely significantly （P<0.01） higher, the milk protein rate was higher （P>0.05）, while the milk fat rate and milk somatic cell count were extremely significantly （P<0.01） lower. [Conclusion] The milk yield and nutritional content of the Kazak mares were higher than those of the Yili mares at the start of lactation （30 days）. The comprehensive lactation performance of the Yili mares was better than that of the Kazak mares at the middle lactation stage （60 and 90 days）. The milk somatic cell count of Kazak mares was higher than that of the Yili mares during the observed lactation periods in this study.

[Objective] To assess the economic benefit of alfalfa planting in a alfalfa planting park, locating in the national modern agricultural demonstration area of Tumed Left Banner, Hohhot City, Inner Mongolia, where the ′high-quality forage technology research project′ is implemented, so as to provide guidance for adjusting the planting structure and promoting the development of the alfalfa industry in this area. [Method] Data of six categories of input factors during alfalfa planting process in the surveyed alfalfa planting park, such as seed, pesticide and mechanical fuel oil, were collected. The primary and secondary output factors were regressed and evaluated using the Cobb-Douglas production function model. [Result] Among the six categories of input factors, the mechanical fuel oil and pesticide inputs had negative influences on profit of alfalfa planting in the primary output model, whereas the remaining inputs had positive impacts, with the seed input having a significant （P<0.05） impact. Seed, chemical fertilizer as well as water and electricity inputs all exhibited a positive connection with alfalfa yield in the secondary output model. The profit output model was: Y_output=4.532 503-0.265 386X_seed+0.638 345X_{chemical fertilizer}-2.988 071X_{water and electricity}+5.506 927X_{mechanical fuel oil}-2.662 652X_labor-2.895 284X_pesticide. The yield output model was: Y_output=18.740 580+1.415 616X_seed+0.252 048X_{chemical fertilizer}+0.371 124X_{water and electricity}+0.497 999X_{mechanical fuel oil}+0.060 733X_labor+0.184 595X_pesticide. The marginal yield of seed, chemical fertilizer, water and electricity, mechanical fuel oil, pesticide and labor inputs were 7.981, 0.472, 0.549, 5.301, 0.475 and 3.176 kg/hm², respectively. Mechanical fuel oil accounted for the highest percentage （44.59%） among the input factors in alfalfa planting. Planting of alfalfa experienced a gradually growing stage of scale reward. The marginal yield of alfalfa seed and mechanical fuel oil inputs was significantly larger than zero. Alfalfa production could be improved by increasing these two inputs. [Conclusion] In this area′s alfalfa production practices, the seed, pesticide and mechanical fuel oil inputs should be boosted, while the other input factors should be kept under control.

[Objective] To assess the factors that influence sheep production costs in Inner Mongolia. [Method] Using pertinent data from the ′National Collection of Cost-benefit Data for Agricultural Goods from the year of 2001 to 2019, a quantitative analysis on the sheep production costs in Inner Mongolia was performed. The regression analysis model was developed using EViews 7.0 software. In total, eight indexes including concentrate and feeding salt fees, forage fees, medical and epidemic prevention fees, breeding fees, death loss fees, grazing equipment fees, repair and maintenance fees, and indirect expenses, were used as explanatory variables to evaluate the effects of diverse production factors on sheep production costs. [Result] At the 5% significance level, the concentrate and feeding salt fees, forage fees, medical and epidemic prevention fees, breeding fees, and death loss fees had considerable （5%） impacts on the production costs of sheep. [Conclusion] The key contributing factors for increasing sheep production costs and lowering profitability include the elevated concentrate and feeding salt fees, forage fees, medical and epidemic prevention fees, breeding fees, and death loss fees.

[Objective] To addresses the current situation and existing problems of man-land relationship in pastoral areas of Inner Mongolia, and to alleviate the fragile ecological environment and backward economic development and promote the orderly and harmonious development of grassland ecological protection and social economy by coordinating man-land relationship in these areas. [Method] Through analyzing the population status, the relationship between population and grassland resource carrying capacity, and the relationship between population distribution and grassland degradation in pastoral areas of Inner Mongolia, the main problems in the relationship between human and lands were explored. [Result] In the years of 2000, 2010 and 2015, the grassland resource carrying capacity index （LCCI） in pastoral areas of Inner Mongolia was 3.68, 3.88 and 3.89, respectively, all over 1.250. From the year of 2000 to 2015, with the increase of population in pastoral areas, the LCCI showed an upward trend. Each banner or town in pastoral areas of Inner Mongolia had a grassland degradation index of less than 90%.[Conclusion] In pastoral areas of Inner Mongolia, population distribution was uneven, with the total population and animal husbandry population dense in the southeast and scarce in the west and north. Population overload was characterized the relationship between population and grassland resource carrying capacity in pastoral areas of Inner Mongolia, and the degree of population overload grew from the year of 2000 to 2015.

[Objective] To investigate the effects of different saline-alkali stresses on seed germination and seedling growth of Bothriochloa ischaemum. [Method] The germination of Bothriochloa ischaemum seeds was observed under the stresses of NaCl, Na₂SO₄, Na₂CO₃ and NaHCO₃, respectively. For each saline-alkali species, the Na⁺ concentrations were set at 10, 30, 90, and 270 mmol/L. To reveal the response of seed germination and seedling growth of Bothriochloa ischaemum to varied saline-alkali stresses, using distilled water treatment as the control, the variations in germination percentage, germination index, and mean germination time of the seeds were assessed, and the changes in vigor index, radicle length, and plumule length of the seedlings were characterized. [Result] The seed germination percentage, germination index and mean germination time, as well as the seedling radicle length and plumule length of Bothriochloa ischaemum were all extremely significantly （P<0.01） affected by different saline-alkali species, Na⁺ concentrations, and their interaction. As the Na⁺ concentrations increased, the seed germination percentage and germination index as well as seedling radicle length and plumule length dropped, but the mean germination time elevated. Different Na⁺ concentrations extremely significantly （P<0.01） affected the seedling vigor index as well, and the seedling vigor index declined as the Na⁺ concentrations increased. Different saline-alkali species had significant （P<0.05） effects on the seedling vigor index, while the interaction between saline-alkali species and Na⁺ concentrations had no significant （P>0.05） effects on the seedling vigor index. The ability of seed germination and seedling growth declined as the concentrations of Na⁺ increased, and it was higher under NaCl and Na₂SO₄ stresses than under Na₂CO₃ and NaHCO₃ stresses. [Conclusion] The seed germination and seedling growth of Bothriochloa ischaemum exhibited tolerance to the stresses of NaCl, Na₂SO₄, Na₂CO₃, and NaHCO₃ with a Na⁺ concentration of 10 mmol/L. Its tolerance to neutral salt was higher than that to alkaline salt. The effects of saline-alkali stresses on the radicle growth of Bothriochloa ischaemum seedling were greater than that on the plumule growth.

[Objective] To determine the most effective method for breaking seed hardness of Melilotoides ruthenica cv. Zhongcao No.7. [Method] KNO₃ solution, gibberellic acid （GA） solution, 98% H₂SO₄, hot water, liquid nitrogen, and mechanical abrasion of the seed coat were used to treat the seeds of Melilotoides ruthenica cv. Zhongcao No.7, respectively. With untreated seeds as control （CK）, the seed germination rate, hardness rate, germination potential and germination index, as well as dead seedling rate were calculated using the number of normal germinated seeds and hardness seeds acquired on the 14^th day of germination. The efficacy of various treatment methods on breaking seed hardness was statistically compared. [Result] The hardness rate of the seeds treated with mechanical abrasion reduced to 4% and the germination rate rose to 96%. When the seeds were treated with 98% H₂SO₄ for 25-30 min, the hardness rate decreased to 5% and the germination rate increased to 95%. The germination rate, germination potential, and germination index of the seeds treated with the above two methods were significantly （P<0.05） higher than those of CK , and the dead seedling rate was lower. Both treatments were capable of successfully breaking the seed hardness of Melilotoides ruthenica cv. Zhongcao No.7. In comparison to CK, significant （P<0.05） effects on reducing the seed hardness rate were observed in the treatments of 75 ℃ hot water, 400 mg/L GA solution for 36-48 h, and seed soaking in 0.1% KNO₃ solution, but the decrease range was too little to be useful. The treatment of liquid nitrogen, which substantially elevated the dead seedling rate, was not recommended either. [Conclusion] Considering the high risk of 98% H₂SO₄ treatment, it is recommended that mechanical abrasion of the seed coat be prioritized in breaking hardness of batch seeds of Melilotoides ruthenica cv. Zhongcao No. 7.

[Objective] To assess the effects of two traditional Chinese medicine immune enhancers on immunological response of broiler chicks to Newcastle disease vaccine. [Method] In total, 150 1-day-old male AA broiler chicks were randomly allocated into three groups, a control （CG） group, a Astragalus membranaceus （AM） group, and a Lycium barbarum （LB） group, with 50 individuals in each group. The CG group fed basal diet, while the AM and LB groups were supplemented with 1% AM powder and 1% LB powder in basal diet, respectively. At 14 and 35 days of age, the immune organ indexes were measured. The Newcastle disease virus antibody （NDV-Ab） titer was determined at 14,21, 28 and 35 days of age, and the contents of serum immunoglobulin were evaluated at 14 and 28 days of age. [Result] At 14 days of age, the spleen index （SpI） and bursa Fabricius index （BFI） in the AM group were 31.17% （P<0.01） and 34.86% （P<0.05） higher than those in the CG group, respectively, and the SpI in the AM group was 14.12% （P<0.05） higher than that in the LB group. At 35 days of age, the thymus index （ThI） and BFI in the LB group were 14.29% （P<0.05） and 9.76% （P<0.05） higher than those in the CG group, respectively; the ThI, SpI and BFI in the AM group were 18.37% （P<0.05）, 35.84% （P<0.05） and 15.85% （P<0.05） higher than those in the CG group, respectively; the SpI in the AM group was 19.92% （P<0.05） higher than that in the LB group. Compared with the CG group, the NDV-Ab titer of the LB group was increased by 34.78% （P<0.05） at 28 days of age, while that of the AM group was increased by 118.18% （P<0.05）, 75.00% （P<0.05） and 56.52% （P<0.05） at 14, 21 and 28 days of age, respectively. At 14 and 28 days of age, compared with the CG group, the content of serum immunoglobulin M （IgM） in the AM group was increased by 15.15% （P<0.05） and 11.76% （P<0.05）, respectively, and that of serum immunoglobulin G （IgG） was increased by 7.50% （P<0.05) and 14.15% （P<0.05）, respectively. In comparison to the CG group, the content of serum IgM in the LB group was 12.12% （P<0.05） higher at 14 days of age, and that of serum IgG was 11.32% （P<0.05） higher at 28 days of age. [Conclusion] Dietary supplementation of 1% AM powder or 1% LB powder improved the major immune organ indexes, NDV-Ab titer, and serum IgG and IgM contents of AA broiler chicks. The effects of 1% AM powder was superior.

[Objective] To improve the therapeutic efficacy of Mycoplasma bovis （M. bovis） infections in cattle. [Method] Broth micro-dilution method was used to determine the antimicrobial susceptibility of 74 strains of M. bovis isolated from Ningxia Hui Autonomous Region, China. [Result] Enrofloxacin had the narrowest MIC distribution range, with MIC₅₀ and MIC₉₀ being the smallest, followed by spectinomycin, gentamicin, and kanamycin. The resistance rate of the tested M. bovis strains to spectinomycin was the lowest （12%）, followed by enrofloxacin （22%）, while the resistance rate to gentamicin and kanamycin was the highest and identical （36%）. Isolates from cattle lungs had the highest antimicrobial resistance followed by those from joint fluids, while milk isolates had the lowest. [Conclusion] Enrofloxacin had the best antibacterial activity against the clinical isolates of M. bovis in vitro, however there was high risk in emerging of antimicrobial resistance. Dosage and duration of the antibiotics should be stressed. The strong antimicrobial resistance observed in pulmonary isolates may be related to the high probability of respiratory tract infection with M. bovis and the high frequent use of antibiotics.

Sheep contagious ecthyma, caused by infection of orf virus （ORFV）, is a highly contagious and widespread zoonosis. Healthy sheep infected with ORFV will develop papules, blisters, pustules and ulcers in consecutive order, and eventually verrucous scabs in the hairless areas such as lip, nose, and mouth, resulting in proliferative damage. Lambs are particularly susceptible due to incomplete development of their immune system. After the onset, lambs will have difficulty in feeding and malnutrition, which will affect their growth and development, and severe cases will die from secondary infection.This paper reviews the research progress on contagious ecthyma in sheep from the aspects of etiology, epidemiology, clinical symptoms, diagnostic methods, as well as prevention and treatment measures by referring the recent researches in China and abroad, in hoping to provide references for the prevention, diagnosis, and treatment of this disease in veterinary clinics.

Border disease （BD）, caused by border disease virus （BDV）, is an infectious disease in sheep and goats. This disease brings massive economic losses in livestock production around the world. BDV infection causes reproductive disorders in ewes and deformity, tremor, hairiness in lambs. Interspecies transmission of BDV among sheep, cattle and pigs frequently occurs, posing challenges in diagnosis of BD. There is currently no available vaccines for BD prevention and control. Understanding the prevalence of BD in different geographical regions can thus aid in the prevention of transmission and the optimization of control measures of this disease. Based on the current research, this paper reviews BD from the perspectives of etiology, epidemiology, and diagnostic measures, in hoping to provide a reference for the prevention and control of this disease.