With the improvement of human living standards, the demand for meat, eggs and milk has increased significantly, leading to the rapid development of animal husbandry. Antibiotics have been produced largely because they can improve animal functions and prevent diseases. In the context of global antibiotics abuse, livestock and poultry have become important reservoirs for antibiotics and resistance genes. It is urgent to fully understand the distribution and dissemination of antibiotics and resistance genes transmission in the development of animal husbandry in order to provide a reference for the scientific use and rational control of antibiotics in animal husbandry. The article reviews the current status of antibiotic use in animal husbandry. It summarizes the effects of antibiotic resistance gene contamination on livestock, human health, and wildlife. In addition, it emphasizes that future research should focus on the secondary contamination of livestock manure in the surrounding environment and the diffusion mechanism of antibiotic resistance genes in wildlife habitats in animal husbandry. The aim is to provide a reference for the future healthy development of animal husbandry, scientific control of antibiotics, and related research on antibiotic resistance genes.

As a major intestinal nutrient, butyric acid and its derivatives play an important role in maintaining animal intestinal morphology, regulating the environment of animal intestinal flora, and regulating immunity. Previous studies have shown that butyric acid and its derivatives maintain the intestinal microenvironment of animals mainly by  promoting intestinal cell proliferation and affecting intestinal development, maintain the intestinal barrier by improving the expression of relevant proteins in small intestinal epithelial cells, and maintain the homeostasis of the internal environment by regulating the intestinal environment and stimulating the expression of relevant immune proteins. In terms of regulating energy metabolism, butyric acid and its derivatives directively break down to become energy supply, or serve as an energy intake regulator to affect energy metabolism by regulating related genes,mitochondrial synthetic repair and neural circuits. In addition, butyric acid and its derivatives act as signaling molecules in the immune pathway, regulate the gene and protein expression of immune factors, inhibit the proliferation of cancer cells, and improve intestinal immunity. This article mainly discusses the research progress of the mechanism of butyric acid in maintaining animal intestinal health, in order to provide theoretical reference for the development of butyrate products.

To investigate the cause of caseous exudate in oviducts of growing layers in parts of Shandong,Anhui,Hebei,Ningxia and other regions, bacteria were isolated and cultured from the clinical pathological samples. Morphological,molecular biology,serological,animal regression and drug sensitivity tests for these isolated bacteria were carried out. The results showed that the 13 isolated bacteria were Riemerella anatipestifer, mainly serotype 7, and the OmpA genes had evolved into two branches. The animal regression test could replicate the same clinical symptoms, and the drug sensitivity test showed that the isolated bacteria were more sensitive to florfenicol, doxycycline, spectinomycin and cephalosporins. This study provides a theoretical basis for the isolation and identification of Riemerella anatipestifer from different susceptible hosts and the genetic evolution analysis of strains, and also provides reference for the prevention and control of Riemerella anatipestifer infection in poultry.

Regional optimization and rational distribution of animal husbandry is an inevitable requirement of agricultural supply-side reform and high-quality development. In this paper, the spatial autocorrelation method is used to analyze the geographical agglomeration characteristics of animal husbandry by using the panel data of provincial animal production in China, and the causes of its formation are analyzed. The results show that the animal husbandry in China presents obvious agglomeration characteristics, and the development of animal husbandry in each province is significantly affected by its neighboring provinces. The spatial agglomeration of industry is unbalanced, with “high-high” agglomeration in eastern and central China and “low-low” agglomeration in western China. Livestock husbandry layout is relatively stable, and it will continue to maintain the status in the future. Based on this, this paper puts forward some policy suggestions, such as promoting moderate scale operation, developing professional, market-oriented and integrated industry chain, and improving supporting system of animal husbandry.

Poultry is one of the animals that needs long time light exposure. Scientific and correct light program has a significant impact on the growth and development, sexual maturity, first birth age, and egg production peak of laying hens. It is of great production significance to set the corresponding light program during the different stages of induced molting in fasting and feeding recovery. In this study, 529-day-old Guifei chickens with similar body weight and about 60% egg production rate were used as experimental material. According to the different periods of fasting induced moult, the changes of light regime were divided into four stages, and samples were collected at five different periods: the last day of the first stage (16 h L/8 h D, Before fasting), stage Ⅱ (8 h L/16 h D for 3 days), and stage Ⅲ (10 h L/14 h D for 13 days) (F₀, F₃, F₁₆), and 6 d and 32 d of stage Ⅳ (gradually increasing light exposure by 0.5 h/d to 16 h L/8 h D). The number of follicles, ovarian antioxidant indicators, KIT-PI3K-PTEN-AKT signaling pathway and GDF9 gene expression were measured to explore the role of light program in the process of fasting induced molt. Results showed that the levels of FSH, LH, E₂ and P₄ in serum decreased when light exposure was shortened（P<0.001）, and the activities of superoxide dismutase (SOD)(P<0.05) and glutathione peroxidase (GSH-PO) (P<0.001) increased. In particular, primordial follicles were likely to be activated, leading to the increase of numbers of small yellow follicles(P<0.01), primary follicles and secondary follicles(P>0.05). When the light was gradually restored, the expression of KIT and PI3K was continuously high(P<0.001), the expression of PTEN decreased(P<0.01), and the expression of AKT was basically unchanged(P>0.05). The serum levels of reproductive hormones and ovarian antioxidant levels returned to the pre-test state, but the overall number of follicles increased. The results suggest that scientific and reasonable light program during fasting and molting has an auxiliary effect on the remodeling of ovarian function.

This study aimed to investigate the genetic diversity of local cattle breeds. In this experiment, blood and hair samples were collected in different regions from Wannan cattle, Leiqiong cattle, Naqu yak and Haizi buffalo, and genomic DNA was obtained. mtDNA COI, Cytb and D-loop genes were amplified by conventional PCR technique, and barcode sequences were obtained by Sanger sequencing, and then their genetic information was explored. The results showed that the A/T content of the mitochondrial genes of the four cattle species were significantly higher than the G/C content, with a significant anti-G bias, and all of them showed high genetic diversity, among which the Naqu yak was particularly outstanding. The use of COI and Cytb protein codons also showed a certain preference. The NJ phylogenetic tree constructed based on Cytb gene showed the best performance and was able to cluster the four cattle species better, which was more suitable for the exploration of phylogenetic relationships in this paper.

Black soldier fly larvae have good application prospects in the resource utilization of kitchen waste. To investigate the effect of spiciness on the growth of black soldier fly larvae, seven different spiciness gradient diets (capsaicin concentration of 0, 0.2, 0.4, 0.6, 0.8, 1.0 and 1.2%) were fed to 7-day-old black soldier fly larvae in this study. The results showed that the feed to gain ratio of the 0.8% capsaicin group was significantly lower than that of the 0.6% capsaicin group (P<0.05), but there was no significant difference with other groups. The larvae in the 0.8% capsaicin group had the lowest dry matter content and were significantly lower than those in the 0.6% and 1.2% capsaicin groups (P<0.05). There were no significant differences in other indicators such as growth performance, survival rate, conversion rate and waste reduction index of black soldier fly larvae (P>0.05). The results showed that the 0.8% capsaicin group had the least nutrients converted from feed, and the 0.6% capsaicin group had the lowest conversion efficiency. Therefore, the larvae of black soldier fly show great tolerance to spiciness, and the results of this study will provide basic data for black soldier fly larvae in the resource utilization of kitchen waste.

To analyze the composition and diversity characteristics of the gut microbiota of healthy geese and the surface environmental microbiota of goose house, this experiment used healthy adult Taihu geese as the research subjects. Gizzard, proventriculus, duodenum, jejunum, ileum, and cecum contents were collected, and feces from geese and environmental samples were aseptically collected. Bacterial genomes were extracted, and high-throughput sequencing was performed using the IonS5TMXL platform to analyze the abundance and structural characteristics of the gut microbiota of geese and the environmental microbiota of goose houses. The results showed that the species richness of the proventriculus content microbiota was relatively high, significantly higher than the microbiota of the jejunum, ileum, and cecum (P<0.05). The cecum microbiota exhibited the highest diversity, with its Shannon value significantly higher than that of the duodenum, jejunum, and ileum (P<0.05), greater than that of the gizzard and proventriculus microbiota, but the difference was not significant (P>0.05). In terms of α-diversity indicators of the environmental microbiota in goose houses, except for the Simpson value being significantly higher than that of the ileum (P<0.05), the other indicators did not show significant differences compared to the various segments of the digestive tract (P>0.05). β diversity comparisons revealed that the microbiota structures of the duodenum, jejunum, and ileum contents of geese were relatively similar, while the cecum and fecal microbiota had closer genetic and compositional distances. The microbiota structures of the gizzard, proventriculus, and goose house environment were similar. Different absolute dominant microbial species were found in the contents of various segments of the goose digestive tract, with significant differences in abundance. The absolute dominant phyla (relative abundance greater than 5.00%) in the healthy gizzard, proventriculus, and small intestine segments (duodenum, jejunum, and ileum) contents were Firmicutes, Cyanobacteria, and Proteobacteria, with the duodenum also including Campilobacterota. The absolute dominant phyla in the cecum contents were Firmicutes and Bacteroidetes, while in the goose house environment, the absolute dominant phyla were Firmicutes and Proteobacteria. Similarly, there were spatial differences in the distribution of dominant genera, with Bacteroides being the absolute dominant genus in the cecum (25.81%). In conclusion, the spatial distribution of the segments of the goose digestive tract significantly influenced the abundance and diversity of the microbiota, while the diversity of the environmental microbiota in goose houses was relatively consistent with that of the various segments of the digestive tract, with different absolute dominant microbial species colonizing different segments of the digestive tract.

The aim of this study was to investigate alterations in blood physiological and biochemical parameters of Xinong Saanen dairy goats at different lactation stages and the correlations among these parameters to reflect the physiological and metabolic status and overall health conditions of dairy goats at different lactation stages. Blood samples from 150 Xinong Saanen dairy goats at different lactation stages were collected to determine their blood physiological and biochemical indicators for correlation analysis, in order to explore the influence of non-genetic factors on blood biochemical indicators in Xinong Saanen dairy goats. The findings indicated that: (1) lactation stage significantly influenced various blood parameters such as total protein (TP), albumin (ALB), globulin (GLB), albumin/globulin ratio (A/G), glucose (GLU), total cholesterol (TC), and triglyceride (TG) in Xinong Saanen dairy goats. (2) Significant correlations were observed among TP and GLB, ALB and A/G, ALB and BUN, A/G and GLB, A/G and GLU at different lactation periods (P<0.05). Blood biochemical indicators are significantly affected by lactation periods, and the significant correlations have been observed among the blood biochemical indicators in dairy goats. These findings comprehensively reflect the health and physiological status of dairy goats, providing theoretical references for improving goat milk quality, adjusting nutritional supply, and managing goat farms.

With the sudden outbreak of COVID-19 epidemic as the entry point, the outbreak area and the non-outbreak area regarded as a quasi-natural experiment of the impact of some provinces on pork price, the multi-phase DID model was used to investigate the impact of COVID-19 epidemic on pork price in this study. DID-QR model was built to test the processing effect of COVID-19 epidemic on pork price under different initial price growth rates and different institutional environments. The results showed that the outbreak of COVID-19 epidemic led to a sharp rise in pork price, with an average increase of about 10%. The price of pork affected by the epidemic showed a trend of rising, stable, rising again, stable and falling. During the inspection period, the price of pork increased significantly only in the next month, March, June and July, and began to show an obvious downward trend in October. The outbreak of COVID-19 has widened the gap of pork prices in different regions, and the effect of the epidemic on the price is more obvious in the areas where the initial agricultural economic development level is relatively low and the initial economic development level is relatively high. Therefore, according to the heterogeneity of pork prices under different conditions, the government should formulate targeted measures to reduce the impact of sudden external shocks on the pork market by establishing the linkage mechanism of the main links of the industrial chain and improving the public information platform.

The experiment aimed to investigate the effect of plant extracts replacing anti-coccidian drugs on growth performance and fecal coccidian count in broilers. A total of 234 1-day-old healthy yellow-feathered broilers were selected and randomly divided into 3 groups, with six replicates in each group and 13 broiler chickens in each replicate. The test period was 55 days. The control group was fed the basic diet, the anticoccodidian group was fed the basic diet + 500 g/t dinitolmide, and the plant extract group was fed basic diet + 500 g/t plant extract. The results showed that the average daily gain of the anti-coccidian essential oil group from 1 to 21-day-old chicks was significantly higher than that of the anti-coccidian drug group (P＜0.05), and the feed to gain ratio was significantly lower than the drug group (P＜0.05). In the overall period, there was no significant difference in daily weight gain and feed intake between plant extract group and anti-coccidian drug group, and the feed to gain ratio decreased by 6.30%, so did the mortality rate by 10.26% . The number of fecal coccidia at 33 days in the plant extracts was significantly lower than that in the anticoccidia group and control group (P＜0.05). In conclusion, plant extracts can be used as alternatives for anti-coccidian drugs and have promising applicable prospect in animal husbandry.

F₂ individuals of 462 Texel sheep × Altay sheep were selected in this study, including 229 male lambs and 233 female lambs. All the experimental sheep were reared under uniform conditions until 8 months of age and then slaughtered. After slaughter, the tenderness was measured by C-LM4 tenderness meter. Illumina sheep high density (600K) SNP chip was used for genotyping, and the MLM model of GEMMA software was used for genome-wide association analysis of tenderness traits. After quality control, the remaining 613178 SNPs were used for genome-wide association analysis, and a total of 9 potential SNPs were found to be related to tenderness on chromosomes 2, 6, 23, and 24, respectively. Based on the biological functions of genes and related literature, EREG, AREG and PDE1A genes were speculated to be involved in the biological processes of muscle regeneration and muscle fiber formation, and could be used as important candidate genes affecting tenderness. The aim of this study was to locate SNP sites related to sheep tenderness and their important candidate genes by genome-wide association analysis, so as to provide a scientific basis for improving sheep muscle tenderness by molecular biological methods. 

In order to study the relationship between SNPs polymorphism of HMX1 gene and its enhancer mutation and the ovine congenital microtia of sheep, the polymorphism of enhancer and exon in HMX1 gene of 170 Altay sheep was detected by agarose gel electrophoresis combined with PCR sequencing technology. The results showed that 24 SNPs were found in exon 1 and exon 2 of HMX1 gene, and A557T was significantly associated with congenital microtia in sheep(P<0.05); 76bp replication was found in HMX1 gene enhancer, which was significantly associated with congenital microtia in sheep (P<0.01). The results showed that the replication of 76 bp in enhancer of HMX1 gene is the causal mutation of congenital microtia in Altay sheep, which could be used as a molecular marker to eliminate congenital microtia in Altay sheep.

Lueyang black-bone chicken (LBC) and Zhenping black-bone chicken (ZBC) are unique black-bone chicken populations native to Shaanxi Province. Due to their rich nutrition and popularity among consumers, they have substantial commercial value. However, few studies to date have comprehensively elucidated the genomic characteristics of these two populations. In this study, samples were collected from 20 Lueyang Black-Bone Chicken (LBCs) and 20 Zhenping Black-Bone Chicken (ZBCs) for whole genome re-sequencing. Additionally, SNP datasets were compiled by incorporating publicly available data from 110 chickens.  Population structure analysis revealed that the clustering patterns of local chicken populations are related to their geographical location. LBC and ZBC exhibited the closest genetic distance and indicated a mixture of genetic components of Chinese northern and southern domestic chickens. Genetic diversity analysis showed that LBC and ZBC had relatively high observed heterozygosity, faster linkage disequilibrium decay, and lower inbreeding coefficients, indicating that they have rich genomic genetic diversity. This study deepens the understanding of the population structure of Shaanxi local black chicken breeds and has significant implications for the conservation of germplasm resources in LBC and ZBC.

Veterinary Clinical Diagnostics is a laboratory course that involves various skills and abstract operational techniques. This course has traditionally been taught using conventional teaching methods for many years. However, in the flipped classroom approach, the textbook content is divided into different modules, and micro-videos are created to explore the new “four-step method”. This method integrates information technology and autonomous learning. Teaching practice has found that this approach greatly improves students' awareness of active learning of professional theoretical knowledge and active mastery and improvement of operational skills. It also provides new ideas and references for improving the quality and reform of undergraduate experimental teaching.

Tibetan sheep are mainly distributed in the Qinghai-Tibet Plateau and its adjacent areas, with a distinctive external appearance. About 90% of the total population are mixed-colored, while pure white and pure black individuals are rare.  In order to study the relationship between SNPs of ASIP gene and the heredity of Tibetan wool color, this study used pooled sequencing and PCR-SSCP methods to detect the polymorphisms of seven exons of the ASIP gene in four ecological types of Tibetan sheep populations, including the plateau type, the Oula type, the Zhashijia type, and the black Tibetan sheep. Results showed that five mutation sites were found, including g.49396C>G in exon 3 and g.76594G>C, g.76715T>A, g.76732C>G, and g.76811C>A in exon 7. The mutation site g.76715T>A caused the conversion of cysteine to serine at position 126 (C126S). The mutation site g.49396C>G had three genotypes (CC, CG, and GG) in all four ecological types of Tibetan sheep, with the minimum mutation probabilities of 0.416, 0.234, 0.261, and 0.307, and the polymorphic information contents of 0.485, 0.358, 0.386, and 0.424, respectively, indicating moderate polymorphism. Except for the Oula type, the plateau type, black Tibetan sheep, and Zhashijia type were all in Hardy-Weinberg equilibrium. The results showed that the g.49396C>G and g.76715T>A missense mutations in ASIP gene are important sites regulating the inheritance of Tibetan wool color, which can serve as potential genetic markers for the breeding of Tibetan wool color.

Currently, DNA methylation has become one of the research foci in the field of life sciences and medicine, with a rapid increase in related literature. In order to understand the overall development and trends of international research related to DNA methylation, this study used bibliometrics to analyze the DNA methylation-related publications in the Web of Science (WOS) and the China's CNKI database over the past thirty years, and applied VOSviewer software for visualization. The retrieval and analysis revealed a total of 21, 262 DNA methylation-related papers in the WOS database and 25, 664 papers in the CNKI database. In WOS database, the United States has an absolute advantage in the number of relevant papers, with relatively high average citation frequencies and h-indexes. Research directions mainly focus on genetics, biochemistry and molecular biology,and oncology. Keywords primarily include “epigenetics”, “gene expression” and “cancer”.Among them, gene expression is the focus and direction of DNA methylation research. These keywords reflect the wide application and deep exploration of DNA methylation in these fields. In the CNKI database, the main publications are in journals such as Cancer, China Animal Husbandry & Veterinary Medicine, and Journal of Animal Husbandry and Veterinary Medicine. Through the analysis of DNA methylation related literature in WOS and CNKI databases, this study provides valuable information and reference for subsequent research in the field of DNA methylation. 

The study aimed to improve the evaluation accuracy of environmental comfort level of pig house, overcome the coupling of multiple environmental factors of pig house, and avoid the inaccurate problem of using a single environmental factor to evaluate the environmental quality of pig house. According to the environmental breeding standard of pig house, the evaluation index system and weight of pig house comfort level were constructed, the membership functions of environmental factors such as air temperature, humidity, wind speed, CO₂, NH₃ and H₂S were established. A comprehensive evaluation method of pig house multi-environmental factors based on analytic hierarchy process fuzzy theory was proposed, and the real-time monitoring system of pig growth environment comfort level was founded. In this paper, the fuzzy comprehensive evaluation method of pig house comfort level is verified using 24 groups of environmental monitoring data in fattening pig house. The experimental results show that the fuzzy comprehensive evaluation method of comfort degree of pig house with multiple environmental factors established by the system can accurately reflect the air quality of pig house. It provides a scientific decision-making basis for accurate regulation of pig house environment, and has certain application value.

In order to study the effects of different forms of Microplastics (MP) on the migration of heavy metals from livestock and poultry manure in soil, different forms of Polypropylene (PP) were selected as raw materials for Microplastics, and layer hen's manure was taken as the manure source model. Two kinds of micro-plastic fragments with different sizes and two kinds of micro-plastic fibers with different diameters were added into the experimental soil with the proportion of 1% and 10% respectively. The results showed that different forms of microplastics had different effects on the migration of different heavy metals. The microplastics in soil inhibited the migration of Cu, and the smaller the form, the stronger the inhibition. The optimal absorption effect of Cu was observed in small fragmented plastics. Additionally,the microplastic in soil accelerated the migration of Zn and Cd,but exerted little impact on the migration of Pb. The soil electrical conductivity was slowed down under the influence of fibrous microplastics. 

The microbiota-gut-brain axis is involved in different physiological processes such as metabolism, immune responses, and behavioral responses which exerts important effects on health and growth. Herein, the interactions of microbiota-gut-brain axis of Hu sheep was investigated by multiomics in present study. The results of 16S rRNA gene sequencing analysis showed that Firmicutes, Bacteroidetes, Christensenellaceae_R-7_group, Enterococcus, Oscillospiraceae_UCG-002, and Prevotellaceae_UCG-004 were the dominant microbial taxa in the gut microbiota of Hu sheep. In combination with the colon and brain transcriptome analysis, it is found that estrogen signaling pathway may be the key functional pathway that contributes to the establishment of the microbiota-gut-brain axis of Hu sheep. Additionally, it was also found that Eubacterium and Ruminococcus may be the key bacteria which could modulate the microbiota-gut-brain axis of Hu sheep. These findings could provide basic knowledge for improving the temperament, behavior, and production performances of Hu sheep through modulating the microbiota-gut-brain axis by nutritional intervention.