In order to provide reference for the selection of appropriate methods for aflatoxin B₁（AFB₁） detection in laboratory, the detection performance of AFB₁ in feedstuffs by HPLC with photochemical derivatization, HPLC with trifluoroacetic acid derivatization and LC-MS/MS were verified and compared in this study. The results showed that HPLC with photochemical derivatization and HPLC with trifluoroacetic acid derivatization had good linear range and correlation coefficient （R≥0.999 97）, the recovery rates of AFB₁ ranged from 88.4% to 104.6%, and the precisions were below 5%; the correlation coefficient （R） of LC-MS/MS method was ≥0.999 00, the recovery rates of AFB₁ ranged from 85.3% to 96.8%, and the precisions were below 3%. The combined data suggest that for the determination of AFB₁ in feedstuffs, HPLC with photochemical derivatization has the advantages of simplicity of operation, high sensitivity and good stability, but had higher cost; HPLC with trifluoroacetic acid derivatization has lower cost, but is susceptible to the interferences from matrix in sample, and the operating procedures are complicated; LC-MS/MS has higher qualitative accuracy, but has lower quantitative accuracy and the highest cost in the three methods.

In order to screen the bacteria that can more effectively degrade the cellulose components in composts, the bacterial strains with certain cellulose-decomposing ability were isolated from the soil samples using sodium carboxymethylcellulose as carbon source. Subsequently, the isolates were phenotypically identified with Gram′s staining method and were molecularly confirmed by 16s rDNA sequence analysis. Further screening test was carried out among the obtained isolates by using cellulose-Congo red medium, filter paper degradation test and cellulase activity determination test. The results showed that a total of 41 strains of cellulose-degrading bacteria were isolated from soil samples, and 6 of them exhibited better hydrolysis capacity in cellulose-Congo red medium. Among the 6 isolates, 3 strains designated as XQ-8,XQ-10 and XQ-11 had better performance in filter paper degradation test. The 16s rDNA-based identification revealed that 2 of them were Cellulomonas gilvus and the remaining one was Pseudomonas putida. The cellulase activity of these 3 strains were determined as （28.95±1.48） U/mL, （54.70±1.56） U/mL and （58.85±3.75） U/mL, respectively. In conclusion, this study obtained 3 strains of cellulose-degrading bacteria with higher cellulase activity from wetland soil, which may provide potential high-effective cellulose-degrading bacterial strains for the development of manure composting starter.

This study aimed to investigate the effects of fermented feed on the production performance and egg quality of Hy-Line Brown laying hens. The experimental fermented feed was prepared using corn and soybean meal as fermentation substrates and using lactic acid bacteria and Saccharomyces cerevisiae as fermentation starter. A total of 600 Hy-Line Brown laying hens of 336 days old were randomly divided into 4 groups with 150 hens for each group. The basal diet of experimental groupsⅠ~Ⅲ was supplemented with 3%, 5% and 8% fermented feed, respectively, and the control group received no dietary supplementation of fermented feed. The feeding experiment period lasted for 4 weeks, and the indices associated with production performance and egg quality were determined and statistically compared. The results showed that the addition of different proportions of fermented feed to the basal diet could improve the production performance and egg quality of the laying hens to a certain extent. At the second week of feeding the fermented feed, the egg production in the experimental groupⅡwas significantly （P<0.05） increased compared to the control group; at the third week of feeding the fermented feed, the egg production and total egg weight in the experimental groupⅡwas significantly （P<0.05） increased compared to the control group; after 4 weeks of feeding the fermented feed, the egg production, total egg weight, and egg production rate in the experimental groupⅡwas significantly （P<0.05） increased compared to the control group, and the feed/egg ratio was significantly （P<0.05） reduced; the eggshell strength in the experimental groupⅡwas significantly （P<0.05） higher than the control group; the Haugh unit in the experimental groupsⅡ and Ⅲ was significantly （P<0.05） higher than the control group. In conclusion, dietary supplementation of different proportions of fermented feed in the basal diet can improve the production performance and egg quality of Hy-Line Brown laying hens, and the adding level of 5% is recommended.

In order to assess the effects of different decomposing inoculants on the aerobic composting process, the physical properties of composting product of beef cattle manure treated with different decomposing inoculants were compared and analyzed. The results showed that the addition of decomposing inoculants to composting materials accelerated the speed of composting, increased water loss rate and degradation rate of organic matter, speeded up the process of manure decomposing, and shortened the composting cycle. The self-developed decomposing inoculants had the similar effects with the commercially available decomposing inoculants. The developed decomposing inoculants has the effect of accelerating the composting of beef cattle manure.

The grassland of Inner Mongolia covers a wide area, including 33 animal husbandry counties, which occupies an important position in the economic and social development and ecological construction of Inner Mongolia. Constructing ecological pastoral area and realizing the modernization of pastoral area are the important goals of pastoral area construction. Based on the thorough analysis of ecological background, industry development status and existing problems in pastoral areas of Inner Mongolia, we put forward the index system of modern development ideas and construction from the aspects of ecological factors and combination of planting and breeding by referring successful experiences in animal husbandry development at home and abroad, in hoping to lay theoretical basis for the construction of pastoral areas of Inner Mongolia.

In order to cope with the new situation of China′s current economic development, according to China′s basic national conditions and development stage, we must focus on the supply-side reform, promote economic restructuring, improve competitiveness, and facilitate economic development. This is an inevitable choice for China′s economic and social sustainable development, and grassland pastoral areas are no exception. Based on the field investigation and related data analysis on Zhenglan Banner, one of the typical pastoral areas of Inner Mongolia, problems were found in the process of promoting supply-side reform in grassland pastoral area, such as the weak foundation of animal husbandry development, the insufficient science and technology level and intensive development level of animal husbandry, the low degree of systematism, industrialization and scalization, and the lagged characteristic brand benefit. Therefore, in order to achieve sustainable development of grassland ecological economy, it is suggested that grassland pastoral areas should continue to optimize and adjust the supply structure starting from the supply side, accelerate the cultivation of new-type agricultural and livestock business entities, and vigorously develop green animal husbandry.

′No.1 Central Document′ in 2019 highlighted the strategic goal of promoting the revitalization of the dairy industry. Hebei Province also issued the ′Outline for the Revitalization of Hebei Province Dairy Industry′, which called for greater reforms in the structural aspects of the supply side and increased efforts. It is required to support and cultivate local dairy industry leading enterprises, make the dairy brands of Hebei Province such as Junlebao bigger and stronger, and actively explore foreign markets. Based on the policy guidance of dairy industry revitalization, this paper analyzes the current situation and existing problems of forage supply and demand of dairy industry in Hebei Province, and then puts forward an effective way to promote the revitalization of dairy industry.

Alfalfa is an important strategic resource and a high-quality protein source for dairy cow breeding. China′s forage industry started late. Although the planting area ranks second in the world, due to backward technology, the supply of high-quality grass for commodity is inadequate. This paper expounds the current situation and existing problems of market supply and demand of alfalfa industry in China from three aspects of domestic alfalfa commodity supply, market demand and trade, calculates the demand and gap between production and demand of high-quality alfalfa grass, analyzes the impact of Sino-US trade friction on domestic alfalfa and dairy market, and puts forward relevant policy suggestions.

Local colleges and universities play an important role in providing talent support, regional competitiveness, spiritual motivation and technological platform for regional economic development. Local colleges and universities and regional economic development had the relationship of mutual restriction, dependence and promotion. Taking Suihua University as an example, this paper analyzed the existing problems in the process of serving local economy of local colleges and universities. Through connecting the local industrial structure adjustment and transforming social service modes, strengthening the promotion and application of scientific research achievements of local colleges and universities, and encouraging teachers to actively participate in the development of local economy, so as to enhance the ability of local colleges and universities to serve local economic construction.

A variety comparative trial was carried out using the 6 introduced forage sorghum varieties including Zaomu, late-maturing pacetter, Daka, Dalong, Nengsi No.1 and Nengsi No.2. The agronomic characters, fresh grass yield and normal nutritive composition of different forage sorghum varieties were determined and compared. Furthermore, the nutritional indexes of forage were also calculated. The results showed that the highest fresh grass yield was observed in Daka, followed by Dalong, Nengsi No.2, Nengsi No.1, late-maturing pacetter and Zaomu, and the fresh grass yield of Daka, Dalong, Nengsi No.1 and Nengsi No.2 all reached up to 4 000 kg. The analysis of contents of CP, ADF, NDF and ADL showed that the best nutritional quality was obtained in Daka, followed by Dalong, late-maturing pacetter, Zaomu, Nengsi No.2 and Nengsi No.1.

In order to assess the variety adaptability, growth characteristics, yield and nutritional value of multiple cropping oat grass （Avena sativa L.） after wheat, a total of 8 oat grass varieties （Qingyin No.1, Qingyin No.2, Qingyan No.1, Jiayan No.2, Linna, Qinghai Tianyan, Shenglizhe, Tiane） suitable for autumn planting were introduced. The agronomic traits, number of tillers, average width and length of flag leaf, stem diameter, plant height, stem-to-leaf ratio, biomass yield and main nutritive value of various oat grass varieties were determined and compared. The CP content of the same variety during the growth period of 46 days before frosting was higher than the growth period of 76 days, however, the content of NDF, ADF, soluble sugar and fresh and hay yield were lower than the growth period of 76 days; according to the growth rate and height data of 30 days after frosting, the autumn cold-tolerant varieties of Qingyin No.2, Jiayan No.2 and Linna were suitable for multiple cropping after wheat; stem-to -leaf ratio was negatively correlated with CP content and positively correlated with NDF, ADF and soluble sugar; except for the variety of Tiane, positive correlation between the biological yield per unit area and CP, NDF, ADF and total soluble sugar production were observed in the tested oat grass varieties. In conclusion, the varieties with moderate tillering number, high plant height, long and wide leaves, low stem-to-leaf ratio, high total hay yield and high total nutritional value were Qingyin No.2, Jiayan No.2 and Linna.

As a multifunctional peptide hormone, Ghrelin plays a crucial role in regulating appetite and energy metabolism, participates in other metabolic regulation pathways, and is also closely related to the health of the body. Appetite of ingestion and health is the basis for good growth and development of animals. The investigations on association of Ghrelin with appetite and metabolism regulation as well as health are of great significance for animal production and breeding. In this paper, the factors affecting the synthesis and secretion of Ghrelin, the mechanism underlining the Ghrelin′s regulative role in appetite and metabolism, and the association of Ghrelin with body health are reviewed, in hoping to provide references for the studies on the regulative effect of Ghrelin on ingestion appetite and health.

In recent years, the price of beef has continued to rise in domestic and foreign markets. In China, the gap between market demand and supply is constantly increasing. Fat color is one of the important factors affecting the price and quality of beef. The fat coloring is mainly associated with the deposition of carotenoids in adipose tissue in vivo. Non-genetic and genetic factors are considered to be related to this phenomenon. In this paper, the genetic and non-genetic mechanisms underlining the formation of fat color in beef were discussed. Firstly, the data on effect of beef fat coloring on its price and rating were collected, the reasons involving the formation of yellow fat in beef cattle were analyzed, and the genetic and non-genetic factors influencing the fat color in beef was discussed. Secondly, the metabolism process of β-carotene and two associated genes of BCO2 and BCMO1 were briefly introduced. Finally, the research status of fat was summarized. We hope this review may provide new insights into the further study on fat color in beef.

Based on the MODIS-NDVI remote sensing data from 2003 to 2017, the vegetation changes of Tongliao City have been dynamically monitored and evaluated since the implementation of a series of ecological construction projects such as the Three-North Shelter Forest Program, Conversion of Cropland to Forest and Grassland Program and Comprehensive Management Program of ′Double Million Mu′ at the start of 21^st century. The results showed that the vegetation in Tongliao City generally expressed an increasing trend due to the global warming and the extension of growing season of vegetation, and the annual average of NDVI was elevated from 0.296 1 in 2003 to 0.322 7 in 2017. At the same time, the vegetation cover structure was improved obviously, and the low vegetation cover had been changing into the middle vegetation cover. The NDVI of Jarud Banner was relatively stable and maintained a high level from 2003 to 2017. From the aspect of NDVI changing, the vegetation cover in Kailu County, the certain areas of Horqin Zuoyi Middle Banner and the central and eastern region of Horqin Zuoyi Rear Banner was improved more obvious.

In this paper, the current situation of the development of bio-methane engineering in Guizhou Province was expounded, the problems and difficulties in the development of bio-methane in Guizhou Province were analyzed, the collectable amount of crop straw resources in each city was counted, and the production potential of bio-methane was calculated, in hoping to provide reference for the preparation and utilization of bio-methane.

Peony seed oil is a kind of golden-colored oil extracted from peony seed by different extraction processes. Studies have shown that the main components of peony seed oil include fatty acids, unsaponifiables and trace elements. Peony seed oil has many pharmacological functions such as antioxidant, hepatoprotective, hypolipidemic and hypoglycemic effects. Through the systematic review of the relevant literatures on peony seed oil, the research progress of the chemical components and pharmacological activities of peony seed oil was expounded, in hoping to provide theoretical reference for the further study of peony seed oil.

Maternal behaviors in mammals mainly include nesting behavior, lactation behavior, newborn guarding behavior and caring behavior. In swine production, maternal behavior influences the rearing behavior of sows on piglets and the communication between sows and piglets, and has direct impacts on physiological and psychological health of sows and growth and development of piglets, thereby affects the production performance and economic benefits of pig farms. With the rise of modern intensive pig farming, the pig industry has developed rapidly and its economic benefits have been improved. However, the modern intensive feeding has many restrictive factors for sows to express their maternal behavior and for piglets to learn how to express their normal behavior. In this paper, the effects of modern intensive feeding and open feeding mode on maternal behavior in sows and their impacts on pig production were reviewed.

Backfat thickness is an important indicator for improving the production and productivity of the porcine herd, it can be used to evaluate the carcass composition of animals, especially for carcass fat. Animal energy storage is mainly in the form of adipose tissue, and body weight loss is mainly caused by fat metabolism. In the process of modern pig raising, sow reproductive performance is one of the important indicators to measure the economic benefits of the pig industry. Body fatness is a significant index for measuring the body condition of sow. Body fatness is closely related to the fat content of sow, which can effectively reflect the nutritional reserve. The sow′s body fatness condition is closely associated with its reproductive performance, while the reproductive performance of sows directly determines the breeding economic efficiency of the pig farm. With the rapid development of the large-scale pig industry, more and more pig farms have begun to accurately adjust the sow′s body condition through backfat measurement. Based on the determination of backfat and combined with the different physiological stages of the sow, the corresponding feeding standards and nutritional standards are formulated to improve the reproductive performance of the sow to maximize the production efficiency. This paper introduced the ultrasonic backfat measurement technique and its key points, and reviewed the relationship between backfat thickness and reproductive performance of sow, in hoping to provide reference for improving the reproductive performance and meat quality of sow.

Animal quarantine is not only the core part of animal epidemic prevention, but also an effective way to ensure the quality of animal products. Standardized animal quarantine can reduce or control the occurrence of infectious diseases of livestock and poultry. This paper mainly introduces the collection principles and quarantine methods of animal quarantine samples, in hoping to provide reference for the related researchers.

Veterinary Microbiology experiment is an important basic course for veterinary medicine and related majors in colleges and universities which aims to enable undergraduates to have a good master of the basic knowledge and experimental operation skills of pathogenic microorganisms. This study discusses the practical problems in current Veterinary Microbiology experiment teaching and introduces virtual simulation technology with the advantages of high efficiency, safety and interactivity. Virtual simulation experimental teaching assisted conventional experimental teaching, a ′virtual-actual combination′ teaching mode, can expand the time and space to the utmost, enrich the experimental teaching resources, fully inspire undergraduates′ learning interest and innovative consciousness, reduce the hazard of high-risk pathogenic experiment, improve experimental teaching quality and effect, and also provide new path for veterinary medical education reform and multi-level professional personnel training.

Veterinary Public Health is a comprehensive application discipline serving for human health by utilizing all theoretical knowledge, practical activities and material resources associated with human and animal health. It plays an important defensive role in animal food safety, animal epidemics and zoonosis. In view of the current situation of African swine fever in China, on the basis of expounding the importance of Veterinary Public Health, this paper analyzes the teaching strategies of this curriculum, in hoping to break the cognitive limitation of the specialty of veterinary medicine, strengthen the understanding of connotation of veterinary hygiene, improve the curriculum value, and provide guidance for optimizing teaching contents and improving teaching quality.

This paper analyzed the problems existing in the practical teaching of Animal Production. The reform of the practical teaching content was carried out from the aspects of the teaching content and method innovation, the ′3+1′ practical teaching mode construction, the ′dual-qualification′ teacher training, and the practical teaching evaluation system, etc. The results showed that the comprehensive quality of the undergraduates was improved obviously, and the period of employment adaptation was shortened; the cooperation between colleges and enterprises were more closer, which promoted the subject selection of scientific research and the transformation of its achievements; the evaluation system of practical teaching and the feedback mechanism of enterprise employing had also been established preliminarily, and the hardware and software construction of the practice base had been improved. A set of perfect practical teaching mode was constructed containing Animal Production′s experiment, practice, training, graduation design. With the development of information technology, agricultural colleges and universities still need to improve the practical teaching work, including updating experimental equipment, applying virtual simulation technology, introducing advanced science and technology, and modern farm remote teaching, and so on.

With the introduction of the national standards for the teaching quality in veterinary medicine specialty and the suggestions for professional certification standards, the cultivation of high-quality applied veterinary medicine professionals has become an inevitable trend in the future. The implementation of the ′3+1′ training mode of veterinary medicine is conductive to the cultivation of applied talents, and the ′1′ of production internship, has become a top priority. Therefore, in order to guarantee the corresponding teaching quality of production practice, it is necessary to establish a teaching system of production practice for veterinary medicine in the ′3+1′ training mode and an evaluation system for production practice teaching. Meanwhile, a teaching production practice base and management mode adapted to the ′3+1′ training mode should also be established. By strengthening the construction and management of production practice teaching, the practical ability and employability of the undergraduates is improved.