In this study,the transfer factor（TF） in yak spleen was extracted by using freezing-thawing-dialysis method. The physical and chemical properties of the extracts, such as clarity and p H values, were determined and analyzed. The sterility test,pyrogen test, safety test, allergy test and in vitro antibacterial test were carried out to biologically characterize the extracted TF.The results revealed that the TF extracted by the method contained DNA and nucleotide acid, and it was germ free, non- pyrogen,non-toxic, non-allergic, non-antigenic. All of the tested indicators of the extracted TF complied with the quality standard of biological preparation. The results of the study provide experimental basis for the development and application of TF in yak spleen.

Xinjiang Brown Cattle, a breed independently cultivated in China, commonly serves as a dual-purpose cattle for both meat and milk production. This breed has a series of superior characters, such as cold resistance, roughage resistance, strong adaptability and resistance, and is suitable for grazing in grassland. In attempt to screen the hybrid combination with obvious heterosis and optimal economic performance, the hybridization tests were conducted by using Xinjiang Brown Cattle（BD） and different breeds of beef cattle, including South Devon Cattle（ND）, Red Angus Cattle（AG） and Beef Simmental（XM）. The results revealed that the birth weight of ND ×BD combination was higher than the other two combinations. The AG ×BD combination has the lowest birth weight. With the increase of months of age, the body weight of AG×BD combination was rapidly increased, exhibiting developmental superiority in early stage. However, from 6 months of age, the disparity in body weight between AG ×BD and the other two combinations gradually vanished. While the chest wide of AG ×BD combination was significantly higher than the other two combinations in 12 months of age, no differences were observed in the other indicators. The combined data showed that the optimal hybrid combination was ND×BD, followed by AG×BD and XM×BD.

The present study accessed the impacts of two commercial plant growth regulators, ″Zhuanggenling″ and Chlormequat Chloride（CCC, commercial name ″Aizhuangsu″）, on yield and polysaccharide content of Polygonatum odoratum. The Polygonatum odoratum was treated with 1 000, 2 000 and 3 000 mg/L of ″Zhuanggenling″ and ″Aizhuangsu″, respectively. The results showed that yield and polysaccharide content of Polygonatum odoratum were increased by treatment of different concentrations of″Aizhuangsu″.

This study aimed to evaluate the effect of 17α-methyltestosterone（MT） on m RNA expression of vtg gene in liver of Brachydanio rerio. The male and female Brachydanio rerio were treated with different concentrations of MT for 7 days, and q RTPCR assay were used to determine the m RNA expression of vtg gene in their livers. For female Brachydanio rerio, the m RNA expression of vtg gene in 25 ng/L MT treatment group was significantly reduced after 7 days（P〈0.05）, and that in 50 and 100 ng/L MT treatment group was extremely significantly reduced（P〈0.01）. For male Brachydanio rerio, there were no significant differences in the m RNA expression of vtg gene between 25 ng/L MT treatment group and control group after 7 days（P〈0.05）.However, the m RNA expression of vtg gene in 50 and 100 ng/L MT treatment groups was significantly and extremely significantly increased（P〈0.05 and P〈0.01）, respectively. The results suggest that the vtg gene in liver of Brachydanio rerio is sensitive to MT,and it is potential to serve as a biomarker for MT monitoring in environment.

In present study, the rumen fluid of Duolang Sheep was used as donator to assess the different additive amount（5%,10%, 15%, 20%, 25% and 30%） of grape skin on gas production of protein-enriched diet in vitro. The gas production（GP）,fermentation parameter（a, b, c）, p H values and organic matter digestibility（OMD） were determined to evaluate the nutritional value of grape skin as a feed resource and its optimal additive amount. The results revealed that the GP of the protein-enriched diet added with different amount of grape skin was increased with the extension of fermentation time, and it was significantly higher than that of control group（P0.05）. After fermentation for 72 hours, the highest GP was observed in protein-enriched diet added with 20% grape skin（90.50 m L, 72 h）, followed by 15%（85.67 m L, 72 h）. The lowest GP was observed in protein-enriched diet added with 5% grape skin（76.00 m L, 72 h）. At the end of the fermentation test, the highest OMD was obtained when the additive amount of grape skin was 10%, followed by 25% and 30%. The lowest OMD was obtained when the additive amount was 15%. The combined data showed that when 20% grape skin was added in protein-enriched diet, the relatively higher GP and OMD were obtained.

Soybean lecithin is a kind of vegetable oil with special physical and chemical properties as well as nutritional function.It is widely used in animal feed. It is reported that supplementation of soybean lecithin in porcine feed is able to increase the survival rate and feed conversion rate of weaned piglets as well as improve the reproductive performance of sow. Here, we introduced the physical and chemical properties, physiological function and application in porcine production of soybean lecithin,so as to provide some references for pig workers.

Desert steppe is a type of transition form of steppe and the buffer zone between desert and typical steppe where the population height is sensitive to natural and human factors. The present study assessed the seasonal effect of grazing intensity, one of the human factors, on population height of three constructive species in desert steppe, including Stipa breviflora, Artemisia frigida and Cleistogenes songorica. We found that during the period from June to September, population height of the three constructive species was reduced with the increase of grazing intensity. During the period from early June to September, the population height of Stipa breviflora was gradually reduced. For Artemisia frigida and Cleistogenes songorica, their population height was increased at first and then decreasedfrom May to September, and the maximum was observed in August.

Grassland is one of the most important natural resources in China. Investigations on grassland water conservation and its value are urgently needed and are of realistic significance. In present study, combined with the practical situation of grassland ecosystem in Dongwuqi of Inner Mongolia, we studied the evaluation methods on grassland water conservation and its value and assessed their spatial-temporal variations. The results revealed that in this region, the grassland water conservation in the year of2000, 2005 and 2010 were 1.88 ×10~9, 7.63 ×10~8and 2.01 ×10~9m~3, respectively, and the their corresponding value were 1 350 million Yuan, 547 million Yuan and 1 440 million Yuan, respectively. During the period from 2000 to 2005, the total value of grassland water conservation in Dongwuqi reduced by 59.48%. However, during the period from 2005 to 2010, the grassland water conservation in this region increased by 163.25%.

Tetracycline antibiotics, belonging to broad-spectrum antibiotics, are commonly used in animal husbandry production in China. Due to their low absorptivity in gastrointestinal system, the residues of tetracycline antibiotics are relatively higher in animal manure. The great amount of tetracycline antibiotics is discharged into soil and waterways with animal manure, resulting in potential pollution risk for water environment. Here, we reviewed the current situation of water pollution caused by tetracycline antibiotics in animal manure and its ecotoxicological effect on aquatic organisms, so as to provide references for the control of water environment pollution caused by tetracycline antibiotics in China.

In view of the feeding utilization of crop straw, the feeding value as well as process and preparation technology of crop straw feed was reviewed. Furthermore, the potential and existing problems in feeding utilization of straw in Yongqiao District of Suzhou City of Anhui Province were analyzed, and corresponding countermeasures were also proposed, so as to provide ideas for the construction of circular agriculture of planting and breeding combination and resource saving society.

Improving the economic income of herdsman is currently the core of implementing of ″agriculture（animal husbandry）,rural areas（pastoral area） and farmers（herdsmen）″ work. Therefore, it is necessary to analyze the factors influencing the economic income of herdsmen and explore the effective ways to improving their economic income. Taking Xilinhot of Inner Mongolia as an example, regression analysis was conducted to assess the per capita net income of herdsmen by using multiple linear regression models. We found that the age, grassland area and labor force proportion in family population were positively correlated with the dependent variable of per capita net income of herdsmen. The education duration and business area had no significant influence on economic income of herdsmen.

The purpose of the present study was to evaluate the in vitro antibacterial activity of rifaximin against the common bacterial pathogens associated with bovine mastitis. Agar dilution method was used to determine the minimum inhibitory concentration（MIC）of rifaximin against clinical isolates of E. coli, Streptococci and Staphylococci from dairy cows with mastitis.The MIC range of rifaximin against 19 E. coli strains, 25 Staphylococcus strains and 18 Streptococcus strains were 8-16 μg/m L,0.002-0.06 μg/m L and 0.06-2 μg/m L, respectively. The MIC of the most clinical isolates was similar with that of their corresponding standard strains, indicating that they were sensitive to rifaximin. The combined data suggest that rifaximin exhibits strong antibacterial activity against the common bacterial pathogens associated with bovine mastitis.

The present study assessed the acute toxicity of intramammary infusion of rifaximin on mice by using standard method.The results revealed that the mice received the highest dosage of 5 000 mg/（kg·BW）of rifaximin had no adverse reactions and their dietary behavior was normal. No deaths occurred during the observation period in the highest dosage group. Therefore, it is concluded that the LD50 of intramammary infusion of rifaximin by intragastric administration was higher than 5 000 mg/（kg·BW）,indicating that it is an actually non-toxic level substance.

Modular teaching design is of great application value in teaching reform. Swine Production is one of the main courses in major of animal science of agricultural colleges and universities. Based on the connotation of modular teaching, we designed six teaching modules and described the organization, implement and application effect of modular teaching design.

Network teaching is a new attempt for students and teachers who are accustomed to face to face teaching, but it is also the inevitable trend of teaching needs and science and technological development. It is required by the new teaching mode and system reform that the development direction of teaching should be barrier free mode. In this mode, there are no constraints for time and space; students can enjoy the teaching resources anytime anywhere; teacher resources can also break through the limit of region to realize the share of outstanding teachers. The network teaching mode has the above advantages. In this paper, the development situation and advantages of network teaching are discussed.

The cultivation of college students′ scientific and technological innovation ability is the important content of the innovation quality education,and it is the important means of the talent training mode in colleges and universities. Here, we analyzed the current situation and existing problems of Chinese college students′ scientific and technological innovation ability.Taking the major of animal science of Heilongjiang Bayi Agricultural University as an example, proposal ideas on constructing the training system of scientific innovation ability for the students majored in animal science were offered based on the teaching characteristics of this major. Meanwhile, the cultivation and the implementing methods of scientific and technological innovation ability of college students were discussed, so as to provide the reference on improving the cultivation of college students′innovative ability in science and technology.

Based on the characteristics of teaching in vocational colleges and combined with teaching activities of Environmental Hygiene of Livestock and Poultry, teaching reform was explored from the aspect of teaching staff, teaching contents and methods as well as evaluation system, so as to cultivate the high-skilled talents who can meet the demand of the enterprise.

Domestic Animal Infectious Diseases is a main compulsory course in major of animals and plants quarantine（animals quarantine specialty）, which has sound theoretical basis and feasible applicability. In order to achieve the training objectives of application-oriented talents in local undergraduate colleges and universities, some explorations on application of novel teaching methods, for instance, case analysis method, PBL method, task driven method and other teaching methods, were attempted based on the existing problems in Domestic Animal Infectious Diseases teaching. We hope that the application of the novel teaching methods may stimulate the study interest and exert subjective initiative of the undergraduates, so as to improve the teaching quality of this course.

The extracurricular activities can strongly complement the classroom teaching. In the attempt to stimulate the study interest of undergraduates majored in animal science in Domestic Animal Breeding and to improve the teaching quality of this curriculum, we carried out the extracurricular activities in the teaching of Domestic Animal Breeding by organizing interesting knowledge contest and writing review in the spare time, so as to deepen the understanding on basic knowledge of this curriculum,achieve the established training objectives of this curriculum and improve the undergraduates′ study enthusiasm.

Biological plasticizing technology is currently the most advanced biological specimen preservation technology. Its primary principle is that replacing the moisture in biological specimens with liquid polymer compounds or multi-polymer and subsequently the tissues are plastinated by hardening treatment. The plastinated specimens are non-toxic and tasteless, and it is safe to be touched directly by hands. It is durable and its preservation is antiseptic solutions free. A batch of plastinated specimens of domestic animals and fowls are purchased by College of Animal Science and Veterinary Medicine of Heilongjiang Bayi Agricultural University, and they have already been applied in the classroom teaching. Compared with immersed specimens and models, irreplaceable advantages of the plastinated specimens are experienced by the teachers and undergraduates. Subtle anatomical structure characteristics can be exhibited by the plastinated specimens. Neither teachers nor undergraduates will be affected by the irritation and toxicity of the specimens during the process of teaching and observation. The teaching of Anatomy of the Domestic Animals and Fowls becomes more intuitive and acceptable, which is helpful for improving the teaching quality.

Yaks are mainly distributed in the alpine pasture of Qinghai-Tibet plateau and the dominant cattle breed in animal production of grassland resources in this region. The adverse cultivate environment, extensive management and irrational livestock structure are main factors resulting in low production performance of yaks in this region. We analyzed the above mentioned main factors and proposed some countermeasures to improve the production performance of yaks, such as improving nutrition, scientific breed selection, early weaning, so as to provide references for the scientific cultivation of yaks in this region.

In recent years, with the rapid development of dairy farming industry, Dairy Herd Improvement（DHI） technology is widely used in dairy farms. The DHI report provides information on feeding management, reproduction and mating, udder health,disease control, which renders guidelines for scientific management and mate selection, effective mastitis control and rational cow′elimination and is helpful for improvement of dairy cows production performance and economic benefit. A comprehensive and accurate explanation on DHI report is of great significance for practical problems solving in dairy farms and dairy herd improvement. We analyzed the crucial indicators in a DHI report from a dairy in Ningxia, so as to provide references for the application of DHI report in dairy farms.

We reported a case of infections caused by Haemophilus parasuis in piglets occurred in a pig farm of Taixing, Jiangsu Province in March of 2015. The definite diagnosis was made by a series of diagnostic methods. The infections in piglets caused by Haemophilus parasuis were controlled by using high sensitive antimicrobial agents recommended by antimicrobial susceptibility test. We detailed the process of diagnosis and treatment of this case and the differential diagnosis from infections caused by Streptococcus suis with emphasis on histopathological changes. This report may provide some references for veterinary practitioners in control of infections caused by Haemophilus parasuis.

This study aimed to evaluate the immune effect of a high pathogenic live vaccine of JXAI-R strain on porcine reproductive and respiratory syndrome. Three batches of weaned piglets were immunized with the JXAI-R vaccine and their antibody levels were monitored. The results showed that the antibody effective duration time of the immunized piglets maintained for 11 weeks after receiving single vaccine, and no adverse reaction was observed. It is indicated that the live vaccine of JXAI-R strain is effective for the prevention of porcine reproductive and respiratory syndrome and is safe to use.

Porecine circovirus type 2（PCV2） is the main causative agent of porcine circovirus diseases（PCVD） which is widely spread in swine farm. The infection of PCV is frequently prevalent but is always latent. PCVD is a chronic syndrome and the clinical symptoms of infected swine seem minor. PCVD can be caused by multiple causative agents, and the occurrence of this disease always results in relapse and extension of infection duration, which brings huge economic to swine production. The etiology, epidemiological characteristics and preventive measures of PCVD in scaled intra-breed swine farm are reviewed, so as to provide references for the control of PCVD.