The dairy industry is an important part of the animal husbandry industry, and the dairy product industry chain is one of the most complex food industry chains. Dairy product safety cannot be ignored and is a global issue. Through long-term practice, the Netherlands has established a relatively comprehensive dairy product safety supervision system. Based on this, this paper comprehensively analyzes the regulatory advantages of the Dutch dairy product industry chain from the development status and characteristics of the Dutch dairy industry and the food supervision system. Furthermore, it proposes development recommendations for the supervision of food safety in China′s dairy industry from three aspects: the quality of raw milk, regulatory authorities, and financial support, aiming to promote the high-quality development of dairy product safety supervision in China.

Fermented Chinese herbal medicine combines the pharmacological effects of Chinese herbal medicine with the health benefits of probiotics. During the fermentation process, Chinese herbal medicine offers nutrients to microorganisms and promotes their growth, while the enzymes and metabolites produced by microorganisms stimulate the release of effective ingredients in Chinese herbal medicine, reduce the toxicity of derivative preparations, and also synthesize novel active ingredients to enhance the drug efficacy. The fermentation process also decompose the active macromolecules or polymers into small molecules, facilitating transmembrane transport and aiding in the absorption of active substances by the body. In addition, some microorganisms in fermented Chinese herbal medicine inhibit the proliferation of pathogenic bacteria and work synergistically with Chinese herbal medicine to jointly combat pathogens. Under the background of reducing antibiotics use and replacing antibiotics, fermented Chinese herbal medicine, as a type of green feed additive, has great utilization value and prospects in animal husbandry. This paper summarizes the research progress on the characteristics of fermented Chinese herbal medicine and application in animal production, in hoping to provide references for the further development and utilization of fermented Chinese herbal feed additives.

[Objective] This study focuses on the functional effectiveness of China′s live hog futures market, and evaluate its price discovery efficiency and risk aversion efficacy, to provide a basis for government optimization of hog production capacity regulation and enterprise participation in market-based hedging, thereby maintaining producers′ production incentives and safeguarding consumer welfare. [Methods] Cointegration tests and vector error correction models were employed to reveal the long-term equilibrium relationship and short-term adjustment mechanisms between futures and spot prices. The information share model and permanent-transitory model were used to quantify the contributions of futures and spot markets to price discovery. An ordinary least squares （OLS） regression model and error correction model （ECM） were constructed to estimate the optimal hedging ratio and risk hedging efficiency. [Results] The findings indicate that China′s live hog futures market plays a leading role in price discovery, with a significant long-term equilibrium relationship between futures and spot prices, where short-term price deviations converge toward long-term equilibrium through the error correction mechanism. China′s live hog futures market demonstrates a certain degree of effectiveness in hedging, while also showing potential for further development as a tool for market-based management of hog price risk. [Conclusion] The study results suggest that the government can optimize threshold settings for reserve meat regulation using futures price signals, and the price discovery function of the futures market can provide forward-looking market signals for production capacity early warning mechanisms. Leading hog breeding enterprises can utilize dynamic hedging strategies to stabilize business expectations. These findings provide an empirical basis for improving China's agricultural futures market system and promoting innovation in agricultural risk management tools.

Ventilation in animal housing refers to the exchanging process of internal and external air, which is crucial for maintaining good air quality as well as regulating temperature and humidity in animal housing, and for reducing the risk of respiratory diseases in animals. The primary ventilation patterns in animal housing include natural and mechanical ventilation. Natural ventilation relies on natural forces and is suitable for open animal housing, while mechanical ventilation controls air movement within housing using machinery equipment, offering more flexibility. The factors such as animal species, layout and structure of animal housing, climate and geographical location should be taken into account in selection of ventilation patterns. The comfort of animal housing environment directly impacts the health status and production performance of animals. High temperature and high humidity environment may cause heat stress in animals, and further affects their feed intake, growth and immune function. Accordingly, scientific and reasonable ventilation management is of great significance for maintaining health and improving production efficiency of animals. This paper introduced the commonly used ventilation patterns in animal housing, expounded the impacts of different ventilation patterns on environmental factors, and reviewed the research progress on the effects of ventilation patterns on animals′ physiological and biochemical parameters and production performance, in hoping to provide theoretical basis for the design and construction of ventilation systems in animal housing.

During the process of silage, the anaerobic environment can not be completely achieved by fermentation of silage raw materials alone, which not only results in the increase of pH value and ammonia nitrogen content as well as the decrease of lactic acid content in silage, but also may lead to the fermentation of undesirable microorganisms, affecting the effect of silage. To reduce the loss of nutrients during the fermentation process of silage and to improve the fermentation quality and nutritional value of silage, additives are commonly used in silage preparation. The frequently used additives for silage mainly include the following four types: bacterial inoculants, enzyme preparations, fermentation inhibitors and non-protein nitrogen. Different types of additives improve the fermentation quality of silage through varied ways, further ameliorating the nutritional value and feeding effect of silage. This paper reviewed the research progress on the impacts of different types of additives on sensory quality, fermentation quality and microbial diversity of silage, in hoping to provide a reference for the scientific selection of silage additives.

[Objective] Routine nutrient parameters with high reference value of Albas goat and Ordos fine wool sheep muscle were obtained, which provided reference for nutrition evaluation, product standard revision and publicity. [Methods] A total of 204 biceps femoris and longissimus dorsi muscles were collected from eight breeds of goats and sheep, including Ordos Albas goats, Ordos fine wool sheep, goats and sheep from Alxa, Ningxia and Shanxi. Four routine nutrient contents were determined, and descriptive statistics and orthogonal partial least squares discriminant analysis were performed. [Results] The protein, fat, moisture and ash contents （X±2SD, g/100 g） of Albas goat meat were （22.10±1.41）, （3.95±1.11）, （73.65±1.43） and （1.49±0.31） g/100 g, respectively. The protein content was significantly （P<0.05） higher than that of other breeds of goats and sheep;the fat content is lower than that of Alxa white cashmere goats and Hengshan goats, but the difference is not significant （P>0.05）; the moisture content is significantly higher than that of Hengshan goats （P<0.05）. Samples from core producing areas showed significantly （P<0.05） higher protein content than those from non-core producing areas. The protein, fat, moisture and ash contents of Ordos fine wool mutton were （20.25±1.63）, （5.68±2.16）, （72.61±2.18） and （1.59±0.46） g/100 g, respectively. Intramuscular fat content was significantly （P<0.05） higher than that of other breeds of goats and sheep. The protein content of Ordos fine wool sheep in Wushenzhao Town was significantly （P<0.05） higher than that in the other two towns. The supervised OPLS-DA results of routine nutrients showed that goats and sheep had a clustering separation tendency, with protein and ash being the major contributing factors. When fat was replaced by four comprehensive indicators of fatty acids, the clustering separation was more obvious, and the separation effect of breed/region was also better. The major contributing indicators were ash, saturated fatty acid （SFA）, polyunsaturated fatty acid （PUFA）, monoun-saturated fatty acid （MUFA） and trans fatty acid （TFA）. [Conclusion] Albas goats meat exhibited nutritional advantages with high protein, low fat and strong water-holding capacity. Ordos fine wool sheep showed significantly higher intramuscular fat content compared with other breeds of goats and sheep, indicating that the sensory quality was better. Further research should be carried out in terms of texture indicators.

Cottonseed, as a feed raw material with significant development potential, is rich in crude protein and can partially replace soybean meal in animal diets. However, anti-nutritional factors such as free gossypol present in cottonseed are toxic to animals, and issues including incomplete nutrient release and low nutrient utilization persist. Biological fermentation represents a safe detoxification technology that effectively degrades macromolecular nutrients, enhancing their digestibility and absorption by animals. To improve the utilization efficiency of feed raw materials and alleviate dependence on imported protein sources, the microbial fermentation of unconventional feed resources like cottonseed has become a critical strategy for the sustainable development of animal husbandry. This review summarizes the current research status on cottonseed as a feed, its nutritional components and anti-nutritional factors, the advantages of fermented cottonseed, fermentation techniques, and the progress in applying fermented cottonseed in animal production, aiming to provide a reference for the promotion and application of fermented cottonseed feed in animal production.

Heat stress affects the milking performance of lactating dairy cows through various routes, such as reducing feed intake, altering energy metabolism pattern, activating immune system and causing inflammation, and influencing mammary gland development and function. Alleviating measures against heat stress in dairy farms are usually taken from the aspects of nutrition, management and genetics, while the effect is limited. Understanding the potential mechanisms by which heat stress causes reduction in milk production in lactating dairy cows is crucial for controlling milk production losses resulted from heat stress. This paper reviewed the research progress on the influence mechanisms of heat stress on the milking performance of lactating dairy cows, in hoping to provide references for the scientific formulation of heat stress alleviating measures in dairy cow production.

[Objective] To investigate the effects of calcium ions on the gut microbiota of mice fed a high-fat diet. [Methods] Thirty 6- to 8-week-old male C57BL/6J mice were randomly divided into three groups: a standard diet control group （C group）, a high-fat diet group （M group）, and a high-fat diet supplemented with calcium chloride treatment group （D group）, with 10 mice in each group. The C group was fed a standard diet and given regular drinking water, the M group was fed a high-fat diet and given regular drinking water, and the D group was fed a high-fat diet and given drinking water supplemented with 1.5 g/100 mL calcium chloride. After 11 weeks of continuous feeding, fecal samples were collected from each group. The gut microbiota was sequenced using 16S rRNA high-throughput sequencing technology. Species richness, evenness, and diversity were calculated using Perl and R programming languages, and shared and unique OTUs were compared among samples. Alpha diversity （Shannon index） and richness （ACE and Chao1 indices） were analyzed using QIIME software. Differences in microbiota between groups were analyzed using the Wilcox test and LDA histogram from the R STATS package. The PICRUSt software was used to analyze the species composition information obtained from the 16S rRNA sequencing data, and in combination with the Kyoto Encyclopedia of Genes and Genomes （KEGG） database, the functional genes of the microbial communities in each group were classified and analyzed for enrichment differences. [Results] ①A total of 953 922 valid sequences were obtained from the sequencing of nine samples across the three groups. Analysis of the ACE index, Chao1 index, and Shannon index showed no significant differences in species richness and diversity among the groups （P>0.05）. ②Analysis of species relative abundance at the genus and species levels revealed that the dominant genera in the C, M, and D groups were Dubosiella, Lachnospiraceae NK4A136 group, and Ileibacterium, with relative abundances of 14.34%, 14.49%, and 21.69%, respectively. The dominant species in the C, M, and D groups were Clostridiales bacterium CIEAF 020, Ileibacterium valens, and Ileibacterium valens, with relative abundances of 1.36%, 7.24%, and 21.69%, respectively. ③ Analysis of microbiota differences between groups showed that the D group microbiota differed from the C and M groups, primarily characterized by Ileibacterium, Ileibacterium valens, Proteobacteria, Bacilli, Erysipelotrichales, and Erysipelotrichaceae. ④ PICRUSt prediction of functional gene composition revealed significant differences （P<0.05） between the D and M groups in functional gene pathways such as carbon fixation, pyruvate metabolism, and starch and sucrose metabolism, suggesting that calcium chloride treatment may influence gene expression in these metabolic pathways. [Conclusion] Adding calcium ions to a high-fat diet can change the structure of the intestinal microbiota of mice, increase the number of specific microorganisms, and may affect the metabolic pathways related to energy intake and fat accumulation, providing a new perspective for the application of calcium ions in the prevention of obesity.

As a fundamental link of the modern grassland governance system, digitization of grassland ecological production is crucial for preserving ecological balance, increasing productivity, and fostering the transformation and upgrading of the pastoral economy. Currently, although digital technology is being widely used in monitoring and management of grassland ecological production at all levels, its overall development and implementation is still lagging behind. With a particular focus on the digitization process of grassland ecology and production activity, this paper analyzed the development status, main accomplishments and primary problems in this field at both the national and Inner Mongolia Autonomous Region levels. Furthermore, a series of countermeasures on the digital development of grassland ecological production were made from the perspective of national strategy in response to the numerous shortcomings of the current digital construction of grassland ecology, in hoping to lay a strong technological foundation for the realization of the ecological civilization construction goal of ′green mountains and clear waters are invaluable assets′, as well as for the development of new quality productive forces in grassland.

The total area of salinized grasslands in Hulunbuir City is approximately 460 100 hectares, primarily distributed across New Barag West Banner, New Barag East Banner, Prairie Chenbarhu Banner, and Ewenki Autonomous Banner （collectively referred to as the four pastoral banners）, accounting for 4.6% of the city′s total grassland area. This salinization diminishes grassland productivity and reduces available land, posing significant constraints on ecological development and the advancement of grassland-based animal husbandry in Hulunbuir City, and furthermore, impacting the ecological security of northern China. In light of this, this review presents a comprehensive review of the grassland resources, climatic conditions, and the current state of salinization within these four pastoral banners and summarizes the underlying causes of grassland salinization and relevant management strategies, aiming to provide a reference for optimizing salinized grassland management strategies and enhancing these degraded grassland resources in Hulunbuir City.

[Objective] This study was conducted to assess the mechanisms underlying the protective role of honeysuckle extract against Newcastle disease virus （NDV） infection in pigeon. [Method] A total of 40 healthy 28-day-old American king pigeons without NDV vaccination were selected and subjected to a 7-day adaptive rearing. At the age of 35 days, the experimental pigeons were randomly assigned into a honeysuckle extract protective （KO） group （n=10） or a virus challenge control （OE） group （n=10）. The pigeons in KO group drank the water containing 1.2% honeysuckle extract for 7 consecutive days, and at the age of 42 days, they were intramuscularly injected with 0.5 mL NDV Pi/NJ/CH/4416/2016 strain of pigeon origin with HA potency of 5log2 . The pigeons in OE group drank the normal water and were challenged with the same NDV strain at the same dosage at the age of 42 days. Seven days after challenge, 3 pigeons were chosen from both KO and OE groups. The spleen samples were collected for paraffin-embedded tissue section preparation and for total RNA extraction to construct the transcriptome libraries. RNA-Seq was used to identify differentially expressed genes （DEGs） and to perform GO functional enrichment analysis as well as KEGG pathway enrichment analysis. Four randomly selected significant DEGs identified by RNA-Seq were verified by using qRT-PCR. [Result] The splenocytes of the pigeons in OE group had abnormally enlarged nuclei and white vacuoles, accompanied by a large number of granulocyte infiltration in splenic tissues, while those of the pigeons in KO group had many white vacuoles and minor granulocyte infiltration alone, and no abnormally enlarged splenocyte nuclei in splenic tissues were observed. A total of 374 DEGs were identified in the spleens of the pigeons in KO group by RNA-Seq, of which 112 were significantly up-regulated and 262 were significantly down-regulated. GO functional enrichment analysis demonstrated that 875 DEGs were enriched in 312 GO entries, of which 149 belonged to biological process, 33 belonged to cellular component, and 130 belonged to molecular function. KEGG pathway enrichment analysis revealed that 226 DEGs were enriched in 93 KEGG signaling pathways, including information transmission pathway, metabolic pathway, natural immunity related pathway, and apoptosis pathway. The qRT-PCR validation test showed that the relative mRNA abundance of the 4 randomly selected significant DEGs （LOC110360702, LOC110360688, SFRP5 and CHAD） had the same change trend as the RNA-Seq results. [Conclusion] Honeysuckle extract exerts protective role against NDV infection in pigeon by activating important physiological processes of host such as information transmission, metabolic regulation and immune response. The results obtained in this study provide a scientific basis for further investigation on the molecular mechanism of immune response to NDV infection in pigeon.

[Objective] The aims of the present study were to assess the biological characteristics of Lactobacillus plantarum derived from Yichun forest pig and to comprehensively evaluate its application potential in the development of probiotic preparations. [Method] A lactic acid bacterial strain （P1M1） isolated from the feces of the healthy forest pig in Yichun City, Heilongjiang Province, was biochemically identified and then molecularly confirmed by using 16S rDNA PCR amplification and sequencing technology. The curves of growth and acid production of the strain were drawn, and its tolerance to acid （pH values at 2.0, 3.0 and 4.0） and bile salt （concentrations at 0.15% and 0.30%） were evaluated. The sensitivity of the strain to 13 antimicrobial agents and its inhibitory effect on Staphylococcus aureus （S. aureus） of porcine origin were examined. Tests were also conducted to assess the free radical scavenging ability, exopolysaccharides yield and safety to mice of the strain. [Result] Based on the biochemical and molecular identification results, P1M1 strain was identified as Lactobacillus plantarum （L. plantarum）. L. Plantarum P1M1 strain had glycolytic ability. Its logarithmic growth phase was 2-10 h of cultivation. After 18 h of cultivation, the pH value of its culture medium stabilized at 3.8-3.9. Its 3 h survival rates at pH values of 2.0, 3.0 and 4.0 were （48.97±0.61）%, （64.19±0.94）% and （78.44 ± 1.36）%, respectively, and those at bile salt concentrations of 0.15% and 0.30% were （53.86±1.14）% and （32.87±0.75）%, respectively. It was sensitive to erythromycin, enrofloxacin, norfloxacin, tobramycin, ampicillin, amoxicillin, cefoperazone, cefradine and ceftazidime, and had pronounced inhibitory effect on S. aureus of porcine origin. The scavenging rates of its cell-free supernatant against DPPH free radical, hydroxyl radical and ABTS free radical were （91.65±1.44）%, （87.32±0.22）% and （89.79±0.59）%, respectively, all significantly （P<0.05） higher than those of its intact cell suspension. Its exopolysaccharides yield was （796.73±2.43） mg/L. No death or organ damage was observed after continuous gavages of the L. plantarum P1M1 strain to mice for 2 weeks. [Conclusion] Forest pig derived L. plantarum P1M1 strain shows an early entrance into the logarithmic growth phase, has glycolytic characteristics, strong acid producing ability, and tolerance to acid and bile salt. It is sensitive to various antimicrobial agents and capable of inhibiting the growth of S. aureus of porcine origin. Furthermore, it has strong antioxidant capacity and high exopolysaccharides yield, and is safe for mice. Accordingly, it can be used as a candidate strain for the development of probiotic preparations.

With the continuous development of social economy and the steady improvement of people′s living standards, the public′s attention to the quality and safety of livestock products has also increased. The quality of livestock products reflects the development level of the animal husbandry industry, and the issue of livestock products quality and safety has become one of the critical issues restricting the healthy development of the animal husbandry industry. The livestock products quality and safety traceability system can trace the origin of livestock products and realize the sharing of information throughout the whole process from farm to fork. With the help of the livestock products quality and safety traceability system, the producers can achieve precise feeding and management as well as improve their breeding efficiency, the regulators can achieve precise supervision and improve their management efficiency, and the consumers can achieve worry-free consumption and improve their satisfaction. Accelerating the construction and application of the livestock products quality and safety traceability system is conductive to ensure the quality and safety of livestock products and promote the improvement of quality and efficiency of animal husbandry production. This paper introduced the application status of the livestock products quality and safety traceability system, analyzed the main problems in the application of the system, and put forward countermeasures and suggestions to accelerate the promotion of the system, in hoping to provide references for enhancing the supervision efficiency of livestock products quality and safety as well as helping the high-quality development of the animal husbandry industry.

[Objective] To analyze the immunomodulatory mechanism of miRNA in the MAPK signaling pathway of bovine milk and milk-derived exosomes. [Methods] Key immune miRNAs of MAPK signaling pathway in bovine milk and milk-derived exosomes were screened based on previous sequencing data. Target genes of these miRNAs were predicted using TargetScan and miRanda software, and their bioinformatics functions were analyzed. Finally, the miRNA-mRNA-KEGG regulatory network of immune-related key miRNAs was constructed. [Results] There were 80 key miRNAs in bovine milk and milk-derived exosomes. The target genes were significantly enriched in immune-related GO terms, including "regulation of inflammatory response" （GO:0050727） and "negative regulation of inflammatory response" （GO:0050728）. KEGG pathway analysis revealed enrichment in 335 pathways, with the top five being "Metabolism", "MAPK signaling pathway", "Pathways in cancer", "Endocytosis" and "Carbon metabolism". PDGFRA and PDGFRB genes in the regulatory network mediated immune functions of bovine milk and milk-derived exosomes through MAPK signaling pathway-associated miRNAs. [Conclusion] MAPK signaling pathway mediated the immune resistance in bovine milk and milk-derived exosomes via key miRNAs, such as bta-let-7i, bta-miR-155, bta-miR-34a, bta-miR-499b and bta-miR-106a_R+1_1ssIAC. PDGFRA and PDGFRB genes in the regulatory network regulated by multiple MAPK signaling pathway-associated miRNAs, might be the key genes in the immune regulation of bovine milk and milk-derived exosomes.

[Objective] To isolate and identify Mannheimia haemolytica from sheep in Kaifeng City, Henan Province, analyze its biological characteristics, and understand its drug resistance and the presence of virulence genes. [Methods] A total of 530 nasopharyngeal swabs were collected from sheep with respiratory diseases in 8 sheep farms in Kaifeng City. Mannheimia haemolytica was isolated using Tryptic Soy Agar （TSA）. The isolated strains were identified through biochemical reactions, morphological observations, and detection of the specific gene LKT. Multiplex PCR was used for serotyping of the isolates. PCR was employed to detect virulence genes in the isolates. The sensitivity of the isolates to 12 antimicrobial agents was tested using the Kirby-Bauer （K-B） disk diffusion method. Pathogenicity tests of isolates were conducted using BALB/c mice. [Results] ①A total of 52 strains of Mannheimia haemolytica were identified from the 530 samples, with a detection rate of 9.81%. ②Serotyping of the isolated Mannheimia haemolytica revealed that 17 strains belonged to serotype 1, accounting for 32.69%; 28 strains belonged to serotype 2, accounting for 53.85%; and 7 strains belonged to other serotypes, accounting for 13.46%. ③Detection of 11 virulence genes in Mannheimia haemolytica showed that all genes were detected. The detection rates of gcp, lktC, and nanH were relatively high, at 73.08%, 67.31%, and 65.38%, respectively, while the detection rates of the remaining virulence genes ranged from 17.31% to 51.92%. ④The isolated strains were highly sensitive to cefotaxime, cephalexin, and ceftriaxone, with sensitivity rates of 86.54%, 78.85%, and 84.62%, respectively. The sensitivity rates to the remaining drugs ranged from 11.54% to 46.15%, among which the sensitivity rates to erythromycin, gentamicin, and ampicillin were lower than 20%. ⑤Pathogenicity tests in mice showed that the lethality rates of Mannheimia haemolytica of serotype 1 and serotype 2 were both 100% within 36 hours. [Conclusion] The Mannheimia haemolytica isolated and identified from sheep nasopharyngeal swabs in the Kaifeng region primarily exhibited two serotypes, carried multiple virulence genes, and demonstrated high pathogenicity. The research results provide data references for the rational use of drugs and scientific prevention and control of Mannheimia haemolytica infections in sheep in Kaifeng City.

[Objective] This study aimed to assess the effects of different saline-alkali stresses on seed germination and seedling growth of forage triticale（× Triticosecale Wittmack）. [Method] The solutions of NaCl, Na₂SO₄, Na₂CO₃ and NaHCO₃ were used to simulate the saline-alkali stress environments, with Na⁺ concentrations set at 0 （CK）, 50, 75, 100, 150 and 200 mmol/L for each solution. Seed germination experiments were conducted to evaluate the change patterns of germination percentage （Gp）, germination index （Gi）, mean germination time （MGT）, seedling vigor index （SVI）, embryonic root length and embryonic bud length of forage triticale under the stresses induced by different types of saline-alkali and concentrations of Na⁺, to reveal the response characteristics of seed germination and seedling growth to different saline-alkali stresses. [Result] Different types of saline-alkali, concentrations of Na⁺ and their interactions all had extremely significant （P<0.01） impacts on Gp, Gi, MGT, SVI, embryonic root length and embryonic bud length of forage triticale. With the increase of Na⁺ concentrations, Gp, Gi, SVI, embryonic root length and embryonic bud length of forage triticale decreased, while MGT elevated. Under the same Na⁺ concentration, forage triticale seed exhibited higher tolerance to neutral salt stress than alkaline salt stress. [Conclusion] With the increase of Na⁺ concentrations, the inhibitory effects of different saline-alkali stresses on seed germination and seedling growth of forage triticale enhanced. Alkaline salt posed stronger inhibitory effect than neutral salt. Forage triticale seed showed certain tolerance to the stress induced by the lower Na⁺ concentrations, indicating that it could be planted on the mild saline-alkali soils in China.

[Objective] To investigate the effects of dietary supplementation with selenoglucose on growth performance, meat quality, serum immune indices, and serum antioxidant indices in broilers. [Methods] A single-factor completely randomized design was employed, with 288 one-day-old, weight-matched, healthy, male Cobb 505 white-feather broilers randomly assigned to four groups （A-D）, each comprising six replicates of 12 birds. Group A was fed a corn-soybean basal diet; groups B, C, and D received the basal diet supplemented with 0.15 mg/kg, 0.30 mg/kg, and 0.60 mg/kg selenoglucose, respectively. The trial lasted 42 days and was divided into two phases based on composition and nutritional levels of the basal diet: early stage （1-21 days） and late stage （22-42 days）. At the end of 21 and 42 days, growth performance was measured, and blood samples were collected from broilers in each group to determine serum immune and antioxidant indices. At day 42, breast muscle samples were collected for meat quality analysis. [Results] Regarding growth performance, from 1-21 days, the average daily gain （ADG） in groups B, C, and D was significantly （P<0.05） higher than that in group A; from 22-42 days, the ADG in group D was significantly （P<0.05） higher than that in groups A, B, and C, and the feed-to-gain ratio （F:G） in group A was significantly （P<0.05） higher than that in groups C and D; from 1-42 days, the ADG in group D was significantly （P<0.05） higher than that in groups A, B, and C, and the F:G in group A was significantly （P<0.05） higher than that in groups B, C, and D. In terms of meat quality, the drip loss in groups A and B was significantly higher （P<0.05） than in groups C and D; the shear force in groups A, C, and D was significantly higher （P<0.05） than in group B; the water-holding capacity in group A was significantly higher （P<0.05） than in groups B, C, and D; the cooking yield in group B was significantly higher （P<0.05） than in groups A, C, and D. Regarding serum immune indices, from 1-21 days, serum immunoglobulin A （IgA） levels in groups C and D was significantly （P<0.05） higher than in groups A and B; serum immunoglobulin G （IgG） and immunoglobulin M （IgM） levels in group C was significantly （P<0.05） higher than in groups A, B, and D; from 22-42 days, serum IgA levels in groups C and D was significantly （P<0.05） higher than in groups A and B; serum IgG levels in group C was significantly （P<0.05） higher than in groups A, B, and D; serum IgG and IgA levels in group A was significantly （P<0.05） lower than in groups B and D; serum IgM levels in groups A, C, and D was significantly （P<0.05） higher than in group B. For serum antioxidant indices, from 1-21 days, serum glutathione peroxidase （GSH-Px）, glutathione (GSH), and total antioxidant capacity （T-AOC） levels in groups C and D were significantly （P<0.05） higher than in groups A and B; serum GSH and T-AOC levels in group D were significantly （P<0.05） higher than in group C; from 22-42 days, serum GSH-Px levels in groups B, C, and D was significantly （P<0.05） higher than in group A; serum malondialdehyde （MDA） levels in groups B, C, and D was significantly （P<0.05） lower than in group A; serum superoxide dismutase （SOD） and GSH levels in group D were significantly （P<0.05） higher than in groups A, B, and C; serum T-AOC levels in groups B and C was significantly （P<0.05） higher than in group A. [Conclusion] The optimal dietary selenoglucose supplementation for broilers was determined to be 0.6 mg/kg. Under this condition, broilers exhibited the best comprehensive performance in terms of growth （ADG, F:G）, meat quality （drip loss）, immune function （IgA, IgG）, and antioxidant capacity （GSH-Px, GSH, SOD, T-AOC）.

[Objective] The aims of the present study were to isolate and identify the Staphylococcus aureus （S. aureus） strain from fecal samples of lambs with diarrhoea, and to characterize the antimicrobial resistance and pathogenicity of the isolate. [Method] Four anal swab samples of diarrheic lambs were collected from a sheep farm in Emin County, Tacheng Prefecture, Xinjiang Uygur Autonomous Region, and S. aureus strain was selectively isolated with mannitol salt agar （MSA）. The isolate was identified by morphological observation and 16S rDNA sequence analysis. The in vitro susceptibility of the isolate to 11 antimicrobial agents belonging to 9 categories was analyzed by paper diffusion method. The presence of virulence genes of the isolate was detected by PCR assay. A model of abdominal infection in Kunming mice was established to evaluate the pathogenicity of the isolate. [Result] One suspected S. aureus strain was isolated from the four fecal samples of diarrheic lambs. It formed glossy, moderately raised, golden or lemon coloured colonies on MSA. Gram staining and morphological observation revealed that the isolate was Gram-positive and arranged in the form of grape bunches. The 16S rDNA sequence of the isolate was 100% similar to that of a S. aureus isolate of porcineluny origin from Changsha City, Hunan Province, China. Morphological observation and 16S rDNA sequence analysis confirmed that the isolate was S. aureus. The isolate was resistant to penicillin, clindamycin, cefotiamine, rifampicin and erythromycin, and was sensitive to gentamicin, azithromycin, chloramphenicol, norfloxacin, cefoxitin and cotrimoxazole. Out of the 20 virulence genes belonging to 8 classes tested, the presence of sea, seg, sei, eta, clfA and clfB genes was observed. The LD₅₀ of the isolate for Kunming mice was 2.24×10⁸ CFU/mL, with observable pathological changes in the organs of the dead mice. [Conclusion] One S. aureus strain was isolated and identified from the fecal samples of diarrheic lambs in a sheep farm in Emin County, which exhibited a multi-drug resistant phenotype, harbored multiple virulence genes and had certain pathogenicity. The results of this study provide references for the rational use of medication for the diseases caused by S. aureus infection in sheep in this region.

The use of biological feed as an antibiotic alternative has gained a lot of attention in light of the antibiotic ban in animal feed. Biological feed offers benefits including improving feed quality, enhancing animal production performance, boosting animal immunity and regulating animal gut microbiota, exhibiting an increasing market acceptance. This paper introduced the definition and classification of biological feed, summarized the research progress on the application of biological feed in cattle, sheep and pig production taking fermented feed and bacterium and enzyme synergistic fermented feed as examples, analyzed the problems in the current application of biological feed, and put forward relevant suggestions, in hoping to provide references for the development and application of biological feed.

Long-acting preparations are medications with long-lasting therapeutic effects, which have the advantages of decreased administration frequencies, reduced dosages and less harmful side effects. Long-acting preparations of traditional Chinese medicine that can continuously release drugs are developed on the basis of conventional traditional Chinese medicine pharmaceutical technology by combining with the carrier materials through unique preparation procedures. This paper reviewed the research progress on long-acting preparations of traditional Chinese medicine and the application in exterminating ectoparasite, in hoping to provide references for future research and clinical application of anti-ectoparasitic long-acting preparations of traditional Chinese medicine.

[Objective] To evaluate the safety and nutritional value of animal-derived protein hydrolysate prepared from meat and bone meal of disease-induced dead animals. [Methods] Meat and bone meal from different batches was processed through high-temperature and high-pressure treatment, degreasing, acid hydrolysis, distillative acid removal, neutralization and decolorization, concentration, and drying to collect animal-derived protein hydrolysate. The nutritional components （crude protein, crude fat, crude fiber, and protein digestibility, etc.）, mineral elements （calcium, total phosphorus, copper, iron, zinc, etc.）, heavy metals （arsenic, chromium, mercury, etc.）, prohibited drugs and antibiotics （clenbuterol, sulfonamides, quinolones, etc.）, microorganisms （Escherichia coli, Salmonella, etc.）, mycotoxins （vomitoxin, aflatoxin B₁, etc.）, and nucleic acids of major porcine pathogens （African swine fever virus, porcine reproductive and respiratory syndrome virus, etc.） were detected. Twenty-four healthy Duroc × Landrace × Yorkshire weaned piglets of similar age and body weight were selected and randomly divided into three groups. The control group was fed a basal diet, while experimental groups 1 and 2 were fed the basal diet supplemented with 0.1% and 0.5% animal-derived protein hydrolysate, respectively, for 35 days. Growth performance, diarrhea incidence, and serum immune, antioxidant, and biochemical parameters were measured. [Results] The animal-derived protein hydrolysate had a dry matter content of 94.04% and a crude protein content of 68.74%, with crude ash was rich in multiple mineral elements, including calcium, phosphorus, and iron exceeding 1 g/kg, and other trace elements exceeding 1 mg/kg. In terms of safety, the heavy metal mercury was not detected, and lead, cadmium, chromium, and total arsenic levels were below 1 mg/kg. No residues of prohibited drugs, harmful microorganisms, or nucleic acids of common porcine viruses were detected. Deoxynivalenol was detected at only 0.31 mg/kg, while other toxins were absent. The total bacterial count was 809 CFU/g, compliant with the Feed Hygiene Standard （GB 13078—2017）. In the weaned piglet trial, compared to the control group, diets supplemented with animal-derived protein hydrolysate significantly （P<0.05） increased average daily gain, significantly （P<0.05） reduced feed-to-gain ratio, and highly significantly （P<0.01） decreased diarrhea incidence. Additionally, it significantly （P<0.05） increased serum total protein and immunoglobulin A levels, highly significantly （P<0.01） increased immunoglobulin G levels, and significantly （P<0.05） enhanced the activities of glutathione peroxidase （GSH-Px）, superoxide dismutase （SOD）, and total antioxidant capacity （T-AOC） in plasma. [Conclusion] The animal-derived protein hydrolysate exhibits high safety and nutritional value, with the ability to modulate the body′s immune function.

[Objective] To monitor the antibiotic resistance profiles and the epidemiological distribution of virulence genes in Escherichia coli isolates from selected meat duck farms in Shandong Province. [Methods] A total of 240 cloacal swab samples were collected from four large-scale duck farms in Shandong Province. E. coli was isolated and identified using differential culture media and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF MS）. The susceptibility of E. coli isolates to 11 antibacterial agents was determined using the broth dilution method. Polymerase chain reaction （PCR） was employed to detect the presence of resistance genes and virulence genes in the isolates. [Results] A total of 212 E. coli strains were isolated, with an isolation rate of 88.33% （212/240）. All isolates exhibited resistance to doxycycline and were sensitive to meropenem. High resistance rates were observed against ampicillin （99.05%） and amoxicillin/clavulanic acid （97.64%）. The multidrug resistance （MDR） rate among the isolates was 93.40%. Resistance spectrum analysis revealed that 63 strains were resistant to 9 antibacterial agents, 51 strains to 8 agents, and 47 strains to 10 agents. Among the 21 resistance genes tested, the detection rates of aadA2, strA, strB, bla_TEM, qnrS, mcr-1, and tetA ranged from 52.83% to 94.34%, while qnrD, tetG, and aadA were not detected, with strains co-carrying eight resistance genes being the most prevalent （60 strains）. Among the 18 virulence genes analyzed, yijp, ibeB, OmpA, mat, iucD, fimC, and vat showed detection rates ranging from 54.25% to 98.58%, with strains co-carrying seven virulence genes being the most common （71 strains）. The predominant virulence gene pattern was ibeB-yijp-mat-OmpA-fimC-iucD （14.62%）. [Conclusion] E. coli isolates from meat ducks in certain farms in Shandong Province exhibited severe antibiotic resistance, with a prevailing pattern of co-carrying seven virulence genes. These findings suggest that the isolated duck-derived E. coli may possess significant pathogenic potential, highlighting the need for enhanced monitoring of antibiotic resistance in duck-derived E. coli in this region.

Selenium is one of the essential trace elements for animals, which is involved in a series of biological processes such as anti-oxidation, immunity, reproduction and intestinal bacterial flora regulation. In recent years, among the selenium preparations from different sources, nano-selenium has attracted the attention of animal nutrition researchers both in China and abroad due to such advantages as low toxicity, high bio-availability, good safety and strong antioxidant property, becoming a hotspot in the research field of feed additives. This paper summarized the nature and characteristics, absorption and metabolism mechanism, and biological functions of nano-selenium, and reviewed the research progress on its application in animal production, in hoping to provide references for the development of nano-selenium feed additives and their scientific application in animal production.

[Objective] This study was conducted to characterize the change of functional gene expression of active microorganisms in different fermentation stages of koumiss. [Method] The koumiss samples were collected at the early （12 h）, middle （48 h） and late （96 h） stages of fermentation, and the metatranscriptomic libraries were prepared for high-throughput RNA sequencing. After assembly and functional annotation of the sequencing data, the differentially expressed genes （DEGs） were identified to determine the static enrichment of significant DEGs in GO and KEGG signaling pathways. [Result] The koumiss samples of the early, middle and late stages of fermentation generated 12.17 GB clean reads by metatranscriptomic high-throughput sequencing. Sequence assembly and data analysis demonstrated that the expression of genes involved in metabolic process played a dominant role in the fermentation process of koumiss. The identification and assessment of DEGs exhibited that the number of the down-regulated genes was more than that of the up-regulated genes in pairwise comparison of the koumiss samples collected at the three fermentation stages. GO functional enrichment analysis showed that the GO terms highly enriched by DEGs between the samples of early and middle fermentation stages associated with cellular process, metabolic process, organic ring compound binding, and heterocyclic compound binding. The GO terms highly enriched by DEGs between the samples of middle and late fermentation stages included cellular process and cellular macromolecule metabolic process. The GO terms highly enriched by DEGs between the samples of early and late fermentation stages mainly involved cellular process, organic substance metabolic process, nucleoside binding, ribonucleoside binding, and purine nucleotide binding. KEGG pathway enrichment analysis displayed that there was only one signaling pathway （ribosome） in which DEGs between the samples of early and middle fermentation stages significantly enriched. DEGs between the samples of middle and late fermentation stages significantly enriched in the signaling pathways of ether lipid metabolism, aminobenzoate degradation, mRNA surveillance pathway, and steroid biosynthesis. The signaling pathways of steroid biosynthesis, aminobenzoate degradation, mRNA surveillance pathway, ribosome and ethylbenzene degradation were significantly enriched by DEGs between the samples of early and late fermentation stages. [Conclusion] The differential expression of functional genes of active microorganisms was involved in the fermentation process and dynamically changed in different fermentation stages of koumiss. The results obtained in this study provide references for in-depth understanding the fermentation mechanism and optimizing the fermentation process of koumiss.

[Objective] To screen low-temperature cellulose-degrading bacteria suitable for efficient composting of manure and straw in the Inner Mongolia region. [Methods] Using sodium carboxymethyl cellulose （CMC-Na） as the carbon source, bacterial strains were isolated and preliminarily screened from deciduous humic soil, naturally composted sheep manure, and cattle manure in Inner Mongolia under 18 ℃ culture conditions. Further screening was conducted using the cellulose Congo red degradation zone test, and the taxonomic identity of the isolates was determined via 16S rDNA sequence analysis. The filter paper strip degradation test was employed for additional screening of the isolates. The carboxymethyl cellulase （CMCase） activity of the screened cellulose-degrading strains was measured using the 3,5-dinitrosalicylic acid （DNS） colorimetric method. Finally, low-temperature strains with high cellulose degradation capabilities were obtained. [Results] Under 18 ℃ culture conditions, 30 cellulose-degrading bacterial strains were initially isolated. Following the cellulose Congo red degradation zone test, 15 strains with superior cellulose degradation abilities were selected, belonging to the classes Bacilli, Gammaproteobacteria, Actinobacteria, Flavobacteria, and Betaproteobacteria. Among these, Bacilli and Gammaproteobacteria were the primary dominant groups, with Actinobacteria as the secondary dominant group. At the genus level, Bacillus was the primary dominant genus, followed by Pseudomonas as the secondary dominant genus. Further screening of the 15 isolates using the filter paper strip degradation test yielded 7 strains with enhanced cellulose degradation capabilities. After culturing at 18 ℃, the CMCase activity of these strains was measured, identifying three highly efficient low-temperature cellulose-degrading strains: F-1-1 （Bacillus）, Y10 （Bacillus）, and T11 （Pseudomonas）, with CMCase activities of （29.25±0.98）, （20.73±0.27）, and （20.60±0.14） U/mL, respectively. These three strains also exhibited higher CMCase activity than other strains when cultured at 30 ℃. [Conclusion] This study elucidates the diversity and cellulose degradation capabilities of culturable cellulose-degrading bacteria in certain regions of Inner Mongolia under low-temperature conditions.The three low-temperature strains with high CMCase activity identified in this study represent promising candidates for the development of microbial agents for efficient low-temperature cellulose degradation in manure composting fermentation.

[Objective] To analyze the research trends and hotspots in the regulation of methane emissions in ruminants by plant extracts. [Methods] Relevant literature published from 2003 to 2023 in the field of methane emission regulation in ruminants by plant extracts in the Web of Science （WoS） Core Collection database was collected. Bibliometric visualization tools CiteSpace 6.2.R6 and VOSviewer 1.6.18 were employed to analyze publication volume, contributing countries （regions）, authors, institutions, and keywords, thereby identifying research trends and hotspots in this field. [Results] From 2003 to 2023, a total of 1,145 articles were published in this field of methane emission regulation in ruminants by plant extracts, with an overall upward trend in annual publication volume. Between 2021 and 2023, 374 articles were published, accounting for 32.66% of the total. In terms of countries （regions）, the United States ranked first, with 198 articles （17.29% of the total）. Among authors, WANAPAT M had the highest number of publications （39 articles, 3.41% of the total）. In terms of institutional contributions, Agriculture and Agri-Food Canada ranked first, with 62 articles （5.41% of the total）, and exhibited the highest level of activity and strongest collaboration with external entities. Keywords with high betweenness centrality （>0.1） and frequency included "plant extracts" "in vitro" and "fermentation" indicating their central role in the keyword network and their close connections with other keywords, as well as their significance as core topics in this research field. The literature keywords were clustered into 10 categories: "beef cattle" "Yucca schidigera" "essential oil" "methane emission" "condensed tannin" "meat quality" "greenhouse gas" "plant secondary metabolites" "essential oils" and "natural plant extracts" .The keyword "sheep" had the highest burst strength （14.60） and was a focus during 2007—2013, followed by "populations" （burst strength: 8.98）, which was a hotspot during 2013—2017. Keywords such as "reduce methane emissions" and "nutrient digestibility" were prominent during 2017—2023. [Conclusion] The research trends and hotspots in the regulation of methane emissions in ruminants by plant extracts were clarified. The effects of different types of plant extracts on methane emissions in ruminants and the synergistic effects among various plant essential oils are likely to be key research directions in the future.

[Objective] To understand the production performance advantages of the F₁ generation crossbreds between Huang-huai Meat Sheep and Hu Sheep, providing a reference for the promotion of new Huang-huai Meat Sheep breed resources. [Methods] 90 purebred Hu ewes, ranging from 2 to 4 parities, were selected and synchronized for estrus. Subsequently, 35 randomly selected purebred Hu ewes were artificially inseminated with semen from Huang-huai Meat Sheep rams, resulting in 29 parturient purebred Hu ewes producing 61 Huang-Hu F₁ lambs （experimental group）. The remaining 55 Hu ewes were artificially inseminated with Hu rams, resulting in 53 parturient purebred Hu ewes producing 103 purebred Hu lambs （control group）. Growth traits, including birth weight, weaning weight, weaning survival rate, average daily gain （ADG） from 0-55, 55-90, 90-120, 120-150, and 0-150 days, as well as body height, body length, chest circumference, and cannon bone circumference at birth, 55, 90, 120, and 150 days, were measured and analyzed for both groups. [Results] Regarding birth weight, weaning weight, weaning survival rate, and ADG across different age periods （0-55, 55-90, 90-120, 120-150, and 0-150 days of age）, the single-birth weight of F₁ generation Huang-hu lambs in the experimental group was significantly （P<0.01） higher than that of Hu lambs in the control group; the multiple-birth weight （twins or more） of F₁ generation Huang-hu lambs in the experimental group was significantly （P<0.05） higher than that of Hu lambs in the control group; the weaning weight, weaning survival rate, and ADG across all measured age periods （0-55, 55-90, 90-120, 120-150, and 0-150 days of age） of F₁ generation Huang-hu lambs in the experimental group were significantly （P<0.01） higher than those of Hu lambs in the control group. For body measurements, at birth and weaning, the body height, body length, and chest circumference of F₁ generation Huang-hu lambs in the experimental group were significantly （P<0.01） higher than those of Hu lambs in the control group; the cannon bone circumference of female lambs at birth in the experimental group was significantly （P<0.05） higher than that of female Hu lambs in the control group; at 90, 120, and 150 days, the chest circumference of F₁ generation Huang-hu lambs in the experimental group was significantly （P<0.01） higher than that of Hu lambs in the control group; the cannon bone circumference of female lambs at 120 days in the experimental group was significantly higher （P<0.01） than that of female Hu lambs in the control group; the cannon bone circumference of male lambs at 150 days in the experimental group was significantly higher （P<0.01） than that of male Hu lambs in the control group; the cannon bone circumference of female lambs at 150 days in the experimental group was significantly （P<0.05） higher than that of female Hu lambs in the control group. [Conclusion] Using Huang-huai meat sheep as the sire and Hu sheep as the dam for crossbreeding, the F₁ generation lambs show obvious heterosis in birth weight, weaning weight, weaning survival rate, and chest circumference, and prominent meat production traits, and are therefore suitable for promotion and application in large-scale sheep farms.

[Objective] To systematically evaluate the effects of heat-clearing Chinese herbal extracts on the production performance of heat-stressed dairy cows, providing guidance and references for alleviating heat stress in dairy cows. [Methods] Published literature on the effects of heat-clearing Chinese herbal extracts on heat-stressed dairy cows was retrieved from four databases: PubMed, CNKI, CQVIP, and WanFang, with the search period spanning from the establishment of each database to August 2024. A systematic review method was used to conduct a Meta-analysis of the literature. Review Manager 5.4 software and the SPSAU website were used to analyze the data of the production performance indicators of dairy cows under heat stress, including milk yield, milk fat percentage, milk protein percentage, lactose percentage, and somatic cell count （SCC）. Then, sensitivity analysis, subgroup analysis, and publication bias analysis were carried out. [Results] Based on strict inclusion and exclusion criteria, 10 research articles meeting the conditions of randomized controlled trials （RCTs） were selected, involving 423 dairy cows. The addition of heat-clearing Chinese herbal extracts significantly increased milk yield [SMD=0.87, 95% CI: （0.63, 1.11）, P<0.000 01] and milk fat percentage [SMD=0.43, 95% CI: （0.02, 0.84）, P=0.04] in heat-stressed dairy cows. Additionally, it significantly reduced somatic cell count in milk [SMD=-1.31, 95% CI: （-1.68, -0.95）, P<0.000 1]. No significant effects were observed on milk protein percentage or lactose percentage （P>0.05, P=0.67, 0.49）. Sensitivity analysis confirmed the stability and reliability of the meta-analysis results, and no significant publication bias was detected. [Conclusion] Heat-clearing Chinese herbal extracts can effectively enhance the production performance of heat-stressed dairy cows.

[Objective] To investigate the seed morphology, germination characteristics, and seedling growth of ten Poaceae species in the Hinggan League of Inner Mongolia Autonomous Region. [Methods] Seeds of ten wild Poaceae species （Digitaria sanguinalis, Phleum pratense, Poa annua, Chloris virgata, Elymus sibiricus, Leymus chinensis, Agrostis gigantea, Eragrostis pilosa, Elymus dahuricus and Agropyron cristatum） collected from the grassland area of the Hinggan League were used as materials. Seed length, width, thickness, thousand grain weight, germination rate, germination potential, germination index, vigor index, radicle length, and coleoptile length were measured and compared. Correlation analysis was conducted on these traits, and the quality of the seeds from the ten Poaceae species was comprehensively evaluated using the membership function method. [Results] The seed length and thousand grain weight of Elymus dahuricus were significantly （P<0.05） higher than those of the other Poaceae species. The seed width of Digitaria sanguinalis and Elymus sibiricus was significantly （P<0.05） greater than that of the other eight species. Agropyron cristatum had the thickest seeds, significantly exceeding the other nine species, followed by Elymus sibiricus and Elymus dahuricus. Except for Leymus chinensis, seeds of the other nine species began germinating on the second day. The germination rates of Digitaria sanguinalis and Phleum pratense exceeded 50% on the second day, with cumulative germination rates reaching above 90% from day 3 to day 7. By the end of the experiment, only Eragrostis pilosa and Leymus chinensis had germination rates below 50%. The germination rate, germination potential, germination index, and vigor index of Digitaria sanguinalis and Phleum pratense were significantly （P<0.05） higher than those of the other Poaceae species. Seedlings of Digitaria sanguinalis exhibited the longest radicles, while those of Elymus dahuricus had the longest coleoptiles. Correlation analysis revealed a highly significant （P<0.01） positive correlation among germination rate, germination potential, germination index, and vigor index across the different Poaceae species. Comprehensive analysis using the membership function method indicated that the top three species in seed quality were Digitaria sanguinalis, Phleum pratense and Elymus dahuricus. [Conclusion] This comprehensive study of seed morphology, germination characteristics, and seedling growth of ten Poaceae species collected from the Hinggan League region revealed that Digitaria sanguinalis, Elymus dahuricus, and Phleum pratense exhibited superior overall performance, demonstrating potential for cultivation and promotion in this region.

[Objective] The aim of the present study was to characterize the molecular epidemiology and genetic variation of porcine reproductive and respiratory syndrome virus （PRRSV） in Guangxi Zhuang Autonomous Region. [Method] A real-time fluorescent RT-PCR kit for universal detection of PRRSV was utilized to detect the presence of PRRSV in a lung tissue sample collected from the clinically infected pig on a farm in Guangxi Zhuang Autonomous Region. Subsequently, a dual real-time fluorescent RT-PCR kit specific for the PRRSV American classic strain and NADC30-like PRRSV strain were employed to further identify the sample. The GP5 gene was amplified by PCR, and a homologous comparison was conducted between the obtained nucleotide sequence by sequencing and the GP5 gene sequences of both domestic and international PRRSV reference strains retrieved from the GenBank database. Additionally, a phylogenetic tree was constructed. The amino acid sequences derived from the GP5 gene were analyzed by sequence alignment. [Result] The sample was identified as NADC30-like PRRSV positive and designated as GXYL strain. Homologous analysis of the GP5 gene nucleotide sequences indicated that GXYL strain exhibited 61.9% to 93.2% similarity with both domestic and international PRRSV reference strains, sharing the highest homology with PRRSV NADC30 strain from the United States and the lowest homology with PRRSV LV strain of European type. Furthermore, phylogenetic tree analysis based on GP5 gene sequences placed GXYL strain within a branch alongside NADC30-like strains from China and NADC30 strains from the United States, indicating close relatedness among them within a larger branch containing other American type strains. Amino acid comparison analysis derived from GP5 gene sequences identified 7 mutation sites within GXYL strain, among which 2 sites were located at epitope A, 1 site was located at epitope B, and 4 sites were located at signal peptide region. No amino acid insertions or deletions were found. [Conclusion] GXYL strain is a NADC30-like PRRSV strain, suggesting that the surveillance of prevalence and genetic variation in PRRSV should be strengthened in this region.

[Objective] The aims of the present study were to assess the optimal ratio of corn straw and spent Flammulina velutipes substrate as roughage in preparation of fermented total mixed ration （FTMR） for beef cattle, and to provide technical support for the high-value utilization of by-products such as mushroom bran. [Method] For the preparation of roughage, a total of 7 treatment groups with different mixing ratios of corn straw and spent Flammulina velutipes substrate were set up. Total mixed ration （TMR） were made from even mixing of corn straw and spent Flammulina velutipes substrate at the ratios of 8∶2 （T1 group）, 7∶3 （T2 group）, 6∶4 （T3 group）, 5∶5 （T4 group）, 4∶6 （T5 group）, 3∶7 （T6 group） and 2∶8 （T7 group） with addition of beef cattle concentrate supplement at a concentrate-roughage ratio of 4∶6 （fresh weight）. TMR samples from different treatment groups were placed into silage bags, and then compacted, sealed, vacuumized and stored in a dark room to naturally ferment for 60 days to prepare FTMR. The nutritional component and mycotoxin content of the prepared TMR and FTMR samples were measured and statistically compared. Furthermore, the fermentation parameters of FTMR were assessed to determine the optimal ratio of corn straw and spent Flammulina velutipes substrate. [Result]①As the ratios of corn straw to spent Flammulina velutipes substrate decreased, the DM content of TMR gradually reduced, the CP content gradually increased, the NDF and ADF contents generally elevated, and the EE content fluctuated. ②As the ratios of corn straw to spent Flammulina velutipes substrate decreased, the DM content of FTMR gradually reduced as well. Compared with the corresponding TMR, the FTMR in T4 group had the lowest DM loss rate. The CP content of FTMR in T3 and T4 groups were significantly （P<0.05） higher than that in the other groups. Compared with the corresponding TMR, the CP content of FTMR in T3 and T4 groups increased. No significant （P>0.05） differences in EE content of FTMR among different groups were observed. Compared with the corresponding TMR, the EE content of FTMR decreased in T1-T4 groups, but increased in T5-T7 groups. The NDF content of FTMR in T1-T5 groups were significantly （P<0.05） lower than that in T6 and T7 groups, with the lowest NDF content observed in T3 group. Compared with the corresponding TMR, the NDF content of FTMR in T3 and T5 groups decreased. The ADF content of FTMR in T1-T5 groups were significantly （P<0.05） lower than that in T6 and T7 groups. Compared with the corresponding TMR, the ADF content of FTMR in T4 and T5 groups decreased. ③The FTMR samples from all the treatment groups had acidic aroma and good fermentation quality. The pH value of FTMR in T3 group was the lowest, which was significantly （P<0.05） lower than that in the other groups. The pH value of FTMR in T4 group was lower as well. As the ratios of corn straw to spent Flammulina velutipes substrate decreased, the LA content of FTMR showed a trend of first increasing and then decreasing, with T4 group having the highest content, followed by T3 group, both of which were significantly （P<0.05） higher than the other groups. As the ratios of corn straw to spent Flammulina velutipes substrate decreased, the AA content of FTMR exhibited a trend of first increasing and then decreasing, with T5 group having the highest content, followed by T4 and T3 groups. Trace level of PA were detected in FTMR samples from all the treatment groups, and there were no significant differences （P>0.05） among the different groups. Trace level of BA were detected in FTMR in T6 and T7 groups, while the other groups were not detected. The AN/TN ratio of FTMR in T3 group was the lowest. FTMR in T6 and T7 groups had the AN/TN ratio exceeding 10%, while the other groups was less than 10%. The differences in AFB₁, ZEN and OTA contents of TMR and FTMR samples among different groups were not significant （P>0.05）. According to the Feed Hygiene Standard （GB 13078-2017）, the mycotoxin content of the TMR and FTMR samples did not exceed the threshold. ④The main effects analysis showed that the fermentation treatment significantly （P<0.05） reduced the ABF₁ and ZEN contents of TMR, while the treatment of the mixing ratios of corn straw and spent Flammulina velutipes substrate, as well as the combination effect of fermentation and mixing ratios, had no significant （P>0.05） effects on the ABF₁ and ZEN contents of the TMR and FTMR samples. In addition, the fermentation treatment, the treatment of the mixing ratios of corn straw and spent Flammulina velutipes substrate, and the combination effect of fermentation and mixing ratios had no significant （P>0.05） effects on the OTA content of the TMR and FTMR samples. [Conclusion] Based on the comprehensive analysis on nutritional component, mycotoxin content and fermentation quality, the preparation of FTMR with corn straw and spent Flammulina velutipes substrate as roughage was an efficient way to preserve and utilize the by-products such as straw and mushroom bran. Corn straw and spent Flammulina velutipes substrate mixed at the ratios of 6∶4 （T3 group） or 5∶5 （T4 group） had the better performance.

Muscle tissue from livestock such as cattle, sheep, and pigs possesses excellent nutritional value and desirable eating characteristics, making it one of the most important sources of animal protein for humans. However, how to further enhance the meat quality of these livestock remains a focal point for researchers and practitioners in the animal husbandry industry. Livestock muscle tissue is composed of different types of muscle fibers, and the muscle fiber type and its dynamic transformation processes significantly affect the meat's texture, flavor characteristics, and nutritional composition. Muscle fiber transformation is a complex biological process synergistically regulated by multiple factors, including genetics, nutrition, and environment. Therefore, an in-depth exploration of the composition characteristics and transformation mechanisms of livestock muscle fibers, and their effects on meat quality, holds significant theoretical importance. This review aims to systematically elaborate on the research progress regarding the muscle fiber types and their transformation mechanisms in livestock, providing a scientific basis for the improvement of meat quality.

[Objective] This study was conducted to assess the effects of ellagic acid on growth performance, antioxidant function and intestinal barrier function in mice fed aflatoxin-containing diets. [Method] A total of 30 healthy female Kunming mice weighted 18 to 22 g were randomly assigned into a control group, a toxin group or an ellagic acid treatment group, with 10 mice in each group. The control group fed a basal diet, the toxin group fed the basal diet containing 250 μg/kg aflatoxin, and the ellagic acid treatment group fed the basal diet supplemented with 250 μg/kg aflatoxin and 100 mg/kg ellagic acid. The feeding experiment lasted for 35 days. The mice were individually weighed at the beginning and end of the experiment, and the weight gain were calculated. At the end of the experiment, the blood samples of the mice were collected with ophthalmectomy. The serum antioxidant indexes such as total superoxide dismutase （T-SOD） activity, total antioxidant capacity （T-AOC） and malondialdehyde （MDA） content as well as the intestinal barrier function indexes such as diamine oxidase （DAO） activity and D-lactic acid content were determined by using ELISA assay. The jejunal tissue samples of the mice were collected to prepare paraffin section. The morphological structure of jejunal mucosa, jejunal villus height and jejunal crypt depth were observed with HE staining, and the ratio of villus height to crypt depth was calculated. [Result] The final body weight and the weight gain of toxin group were extremely significantly （P<0.01） lower than control group. While the final body weight of ellagic acid treatment group was not significantly （P>0.05） different from toxin group, the weight gain of ellagic acid treatment group was extremely significantly （P<0.01） higher than toxin group. Toxin group had significantly （P<0.05） decreased serum T-AOC activity and extremely significantly （P<0.01） reduced serum T-SOD activity in comparison to toxin group. Ellagic acid treatment group had extremely significantly （P<0.01） elevated serum T-SOD activity compared with toxin group, while no significant （P>0.05） difference in serum T-AOC activity was found between these two groups. An extremely significantly （P<0.01） higher serum MDA content was observed in toxin group than control group, and an extremely significantly （P<0.01） lower serum MDA content was observed in ellagic acid treatment group than toxin group. Toxin group had extremely significantly （P<0.01） higher serum DAO activity and D-lactic acid content compared with control group. Ellagic acid treatment group had significantly （P<0.05） reduced serum DAO activity compared with toxin group,while no significant （P>0.05） difference in serum D-lactic acid content was found between these two groups. The jejunal villi and crypt of the mice in control group exhibited complete morphology, and no abnormal pathological changes were observed. Serious pathological damages were observed in jejunal tissues of the mice in toxin group：the arrangement of jejunal villi was neither neat nor tight, the intervillous space enlarged and even break, and the arrangement of jejunal crypt was also not neat. The jejunal villus height and the ratio of villus height to crypt depth of toxin group was extremely significantly （P<0.01） decreased compared with control group, while no significant （P>0.05） difference in jejunal crypt depth was found between these two groups. The mice in ellagic acid treatment group exhibited alleviated pathological damages in jejunal tissues compared with toxin group：the morphology of jejunal mucosa was basically restored to normal, the villi breakage was ameliorated, and the jejunal crypt arranged more neatly. The ellagic acid treatment group had extremely significantly （P<0.01） increased jejunal villus height and the ratio of villus height to crypt depth than toxin group, while no significant （P>0.05） difference in jejunal crypt depth was found between these two groups. [Conclusion] Ellagic acid alleviates the damages induced by aflatoxin in mice via inhibiting the body weight reduction, enhancing serum antioxidant function and improving jejunal mucosa barrier function.

[Objective] This study was conducted to assess the effects of dietary supplementation of compound enzyme and probiotic preparations on growth performance, serum biochemical indices and antioxidant capacity, and small intestinal morphological development of AA broilers. [Method] A total of 480 one-day-old male AA broilers with similar weights were randomly assigned into a control group and 3 treatment groups （T1, T2, T3）. The control group fed a corn-soybean meal based diet, while the T1, T2 and T3 groups fed the same basal diets containing 0.2 g/kg compound enzyme preparation, 1 g/kg compound probiotic preparation, and 0.2 g/kg compound enzyme preparation+1 g/kg compound probiotic preparation, respectively. There were 6 replicates in each group and 20 broilers in each replicate. The feeding trial lasted for 42 days. The average daily feed intake （ADFI）, average daily gain （ADG）, and feed to gain ratio （F/G） at different growth stages （1-21 days of age, 22-42 days of age, 1-42 days of age) were calculated. On the 21^st and 42^nd day of the trial, blood samples were collected to determine the serum biochemical indices and antioxidant capacity. Samples of duodenum, jejunum and ileum were collected to prepare tissue sections. The villus height （VH） and crypt depth （CD） of each small intestinal segment was observed after HE staining, and the ratio of villus height to crypt depth （V/C） was calculated. [Result] ① Compared with the control group, significantly （P<0.05） higher weight at 21 days of age, ADFI and ADG at 1-21 days of age, and ADG at 1-42 days of age were observed in T1 and T3 groups; T1 group had significantly （P<0.05） increased ADFI at 22-42 days and 1-42 days of age, and had significantly （P<0.05) decreased F/G at 1-42 days of age; the F/G at 1-21 days, 22-42 days and 1-42 days of age in T2 group was significantly （P<0.05） reduced; T3 group had significantly （P<0.05） decreased F/G at 22-42 days and 1-42 days of age. The weight at 21 days of age as well as the ADFI and ADG at 1-21 days and 1-42 days of age in T1 and T3 groups were significantly （P<0.05） higher than those in T2 group. The F/G at 1-21 days and 22-42 days of age in T2 group was significantly （P<0.05） lower than that in T1 and T3 groups, and the F/G at 1-42 days of age in T2 group was significantly （P<0.05） lower than that in T1 group. ② Significantly （P<0.05） reduced serum TG content at 21 days and 42 days of age in T1, T2 and T3 groups was observed compared with the control group. T3 group had significantly （P<0.05） elevated serum TP content at 42 days of age than that of the control group and T2 group. T1 group had significantly （P<0.05） higher serum GLU content at 42 days of age than that of the other groups. ③ There were no significant （P>0.05） differences in serum antioxidant capacity at 21 days and 42 days of age among the 4 groups. ④ Compared with the control group, T1, T2 and T3 groups had significantly （P<0.05） lower CD and significantly （P<0.05） higher V/C of duodenum and ileum; T1 and T3 groups had significantly （P<0.05） increased VH of duodenum; T3 group had significantly （P<0.05） elevated VH of jejunum; T2 and T3 groups had significantly （P<0.05） reduced CD of jejunum. The VH and V/C of duodenum in T1 and T3 groups was significantly （P<0.05） higher than that in T2 group. The VH of jejunum in T3 group was significantly （P<0.05） higher than that in T1 and T2 groups. The CD of jejunum in T1 group was significantly （P<0.05） lower than that in T2 group. The CD of ileum in T3 group was significantly （P<0.05） lower than that in T1 group. [Conclusion] Exclusive or combined supplementation of compound enzyme and probiotic preparations in diet exhibited favorable effects on growth performance, serum biochemical indices and antioxidant capacity, and small intestinal morphological development of AA broilers. The combined supplementation showed a better comprehensive performance.

[Objective] To explore the correlation between body weight and body size indexes of Sadumun ternary crossbred black sheep, and to construct an optimal regression model of body weight-body size indexes for black sheep. [Methods] Sixty 8-month-old Sadumun ternary crossbred black sheep rams were selected for the study, and their chest circumference, body height, body length, body slant length and body weight were determined. The statistical software of SPSS 26.0 was used to carry out correlation analysis, regression analysis and path analysis of the collected data, and then to establish the regression equations. [Results] There was a highly significant （P<0.01） positive correlation between body weight and body size indexes of Sadumun ternary crossbred black sheep, and the correlation coefficient between chest circumference and body weight was the largest, which was 0.755. Path analysis showed that chest circumference, body height and body slanting length were important variables affecting body weight, and had an indirect effect on body weight through body slanting length. The optimal regression equation of body weight and body size index of Sadumun ternary crossbred black sheep was y=0.971x_{chest circumference}+0.629x_{body height}+0.505x_{body slant length}-127.019, and the standardized regression equation was y=0.644x_{chest circumference}+0.333x_{body height}+0.335x_{body slope length} （R²=0.761, P<0.01）. [Conclusion] There was a highly significant （P<0.01） positive correlation between body weight and body size indexes of Sadumun ternary crossbred black sheep. The chest circumference, body height and body slant length had a direct impact on body weight. In the process of breeding, the body weight of sheep could be effectively predicted and increased by optimizing these indexes.

[Objective] The aim of this study was to understand the prevalence as well as antimicrobial resistance and virulence gene distribution of Escherichia coli in sheep in a slaughterhouse in Aksu Prefecture, Xinjiang Uygur Autonomous Region. [Method] A total of 30 samples of lymph node, carcass swabs and feces were collected from the healthy sheep in a slaughterhouse in Aksu Prefecture. Escherichia coli was isolated using selective culture medium, and subsequently molecularly identified using Escherichia coli specific phoA gene. Multilocus sequence typing （MLST） of the isolates was performed by PCR amplification and sequencing. K-B disk diffusion method was used for antimicrobial susceptibility test of the isolates. The presence of the antimicrobial resistance and virulence genes of the isolates were detected by PCR assay. The 96-well plate micro-broth method was used to determine the biofilm formation ability of the isolates. [Result] A total of 14 strains of Escherichia coli were isolated from the 30 samples, with a separation rate of 46.67%. The 14 isolates belonged to 10 MLST types. High resistance rates to sulfamethoxazole-trimethoprim （100%）, penicillin （85.71%） and tetracycline （50.00%） were observed among the isolates. Nine isolates （64.29%） expressed multi-drug resistance phenotype. Twelve antimicrobial resistance genes, including bla_TEM （85.71%）, aph （3′） （71.43%）, tetA （64.29%）, sul1 （57.14%） and sul2 （57.14%） were detected in the 14 isolates, and 8 isolates （57.14%） harboured the typeⅠintegron int-Ⅰgene. Ten virulence genes, including fimH （100%）, yijP （92.86%）, mat （92.86%）, sheA （92.86%）, stx1 （35.71%） and ibeB （28.57%） were detected in the 14 isolates. Ten isolates （71.43%） had the ability to form biofilms. [Conclusion] The sheep derived Escherichia coli strains in the slaughterhouse had abundant intraspecific subtypes, increased antimicrobial resistance and the ability to form biofilms. They also carried multiple antimicrobial resistance and virulence genes, and thus posed a potential threat to animal food safety.

[Objective] The aim of the present study was to analyze the research trend and hotspot of heavy metal passivation during organic waste composting process. [Method] The literature published from 2000 to 2022 and indexed by the Web of Science （WoS） core collection database on heavy metal passivation during organic waste composting process were used as the data source. CiteSpace 6.2.R6 and VOSviewer 1.6.18 bibliometric visualization software were employed to assess the number of publications and the corresponding countries （regions）, authors, institutions and keywords, and to clarify the research trend and hotspot in this research field. [Result] From 2000 to 2022, a total of 1 266 papers on heavy metal passivation during organic waste composting process were published, with an overall upward trend in annual publication volume. From 2020 to 2022, 345 papers were published, accounting for 27.25% of the total number of publications. Chinese scholars led the research field in terms of publication volume by countries （regions）, with 301 papers published, accounting for 23.78% of the total number of publications. From the perspective of publication volume and collaborative relationships among the authors, KALAMDHAD Ajay S and ZHANG Zengqiang had the highest number of publications, and both published 23 papers, accounting for 1.82% of the total number of publications. The highest number of collaborative authors were observed between the teams of ZHANG Jiachao and ZENG Guanming, indicating an intimate collaborative relationship. From the perspective of institutional publication volume and collaborative relationships, the Spanish National Research Council ranked the first with 96 papers published, accounting for 7.58% of the total number of publications. The Spanish National Research Council and the Chinese Academy of Sciences were the most active institutions in this research field and had the closest collaboration with the other institutions. The top 6 keywords with high occurrence frequency were heavy metals, sewage sludge, municipal solid waste, organic matter, soil and compost, with occurrence frequencies of 724, 441, 210, 187, 158 and 158, respectively. Among the top 10 keywords with high occurrence frequency, sewage sludge, bioavailability, growth, heavy metals, municipal solid waste and soil had intermediary centrality greater than 0.1, and their intermediary centralities were 0.78, 0.52, 0.42, 0.30, 0.25 and 0.18, respectively. A total of 10 categories of keywords were clustered in this research field, including sewage sludge, organic amendments, organic fraction of municipal solid waste, greenhouse gas, C/N ratio, heavy metals, organic waste, and so on. The keyword zinc had the highest burst strength at 16.57 and received attention from 2004 to 2015. Biochar, food waste, microbial community, transformation and organic amendments were the dominant burst keywords from 2017 to 2022. [Conclusion] This study clarified the research trend and hotspot of heavy metal passivation during organic waste composting process. The impacts of different organic wastes on heavy metal passivation, the form transformation and stability of heavy metals in organic waste composting, and the enrichment and transfer of heavy metals in composting products may be the focus of the future research.

[Objective] The present study was conducted to evaluate the quality grade of fresh dairy milk in different regions of Inner Mongolia, and to compare the milk yield and quality of dairy cows between agricultural and pastoral areas as well as between large-scale farms and scatter-feed households. [Method] In October 2023, a total of 120 batches of fresh milk samples were collected from large-scale farms in Hohhot City, scatter-feed households in Hohhot City, dairy farms in Hulun Buir City, and dairy farms in Xilin Gol League, with 30 batches each. Production record information of the dairy cows was also collected. The milk composition （milk fat percentage, milk protein percentage, total solids content, non-fat milk solids content, lactose content）, somatic cell count and total bacterial count of the samples collected from different regions were tested, and the samples were subsequently subjected to the quality grade evaluation according to the Quality Grading of Raw Cow Milk （NY/T 4054-2021）. Statistical methods were used to compare the average individual milk yield and milk quality of dairy cows between agricultural area （Hohhot City） and pastoral area （Hulun Buir City and Xilin Gol League）, as well as between large-scale farms and scatter-feed households in Hohhot City. [Result] The milk fat percentage and total bacterial count （6.16%, 83.10×10⁴ CFU/mL) of the samples collected from Xilin Gol League were significantly （P<0.05） higher than those collected from Hohhot City （3.96%, 14.05×10⁴ CFU/mL） and Hulun Buir City （4.15%, 38.94×10⁴ CFU/mL）. The milk somatic cell count of the samples collected from Hulun Buir City （399 900 cells/mL） was significantly （P<0.05） higher than those collected from Xilin Gol League （181 800 cells/mL） and Hohhot City （183 500 cells/mL）. According to the Quality Grading of Raw Cow Milk, the milk samples collected from Hohhot City were determined as extra-premium grade, and those collected from Hulun Buir City and Xilin Gol League were both determined as premium grade. The dairy cows in agricultural area had significantly （P<0.05） higher average individual milk yield and milk lactose content （29.07 kg/d, 5.14%） than those in pastoral area （16.56 kg/d, 4.85%）. The milk fat percentage, somatic cell count and total bacterial count of the samples collected from pastoral area （4.88%, 483 900 cells/mL, 49.52×10⁴ CFU/mL) were significantly （P<0.05） higher than agricultural area （4.05%, 202 000 cells/mL, 13.99×10⁴ CFU/mL）. Significantly （P<0.05） higher average individual milk yield as well as milk non-fat milk solids content and lactose content were observed in the dairy cows in large-scale dairy farms （34.46 kg/d, 9.44%, 5.19%） compared with scatter-feed households （20.71 kg/d, 9.21%, 5.07%） in Hohhot City, while significantly （P<0.05) higher milk somatic cell count was observed in scatter-feed households （232 400 cells/mL） compared with large-scale dairy farms （160 400 cells/mL）. [Conclusion] The quality of fresh dairy milk in Hohhot City was better than that in Hulun Buir City and Xilin Gol League. Dairy cows in agricultural area had higher milk yield and better milk quality than those in pastoral area. The milk yield and quality of dairy cows in large-scale farms were superior to those in scatter-feed households.

[Objective] To investigate the infection of Klebsiella oxytoca in the swabs of pigs from a large-scale pig farm in Kuqa City, and to study its biological characteristics. [Methods] 80 nasal swab samples with respiratory tract infection symptoms were collected from the pig farm, and the bacterial species were identified by bacterial isolation and 16S rDNA sequencing. The drug resistance of the isolated strains was understood by detecting the drug sensitivity of the isolated strains to antibiotics and the carrying of drug resistance genes. The pathogenicity was evaluated by animal infection test. [Results] Bacterial isolation and culture were performed on 80 pig nasal swab samples. After morphological identification, 18 strains of suspected Klebsiella bacteria were initially isolated. After 16S rDNA sequencing and comparison analysis, three of the 18 strains were identified as K. oxytoca. 14 antimicrobial drugs from 10 classes were selected for drug sensitivity test, and threestrains of K. oxytoca were multidrug-resistant strains. The isolates were tested for 20 drug-resistant genes, and a total of 8 resistance genes were detected in the three strains of K. oxytoca, including bla_TEM, tetA, sul1, sul2, tetB, aac （3′）-IIa, aadA and qnrB. It was found that all the three isolates of acid-producing K. oxytoca could cause the death of mice and had strong pathogenicity. [Conclusion] The acid-producing K. oxytoca isolated from the large-scale pig farm showed multidrug resistance, carried multidrug-resistant genes, and had strong pathogenicity to mice. The results of this study provided basic data for the prevention and control of acid-producing K. oxytoca in this large-scale pig farm in Kuqa.

[Objective] To investigate the infection status and molecular genetic characteristics of bovine rotavirus in neonatal calves from an introduced dairy farm in the Kashgar region of the Xinjiang Uygur Autonomous Region. [Methods] Fecal samples were collected from 50 calves under three months of age at the dairy farm in Kashgar. The presence of bovine rotavirus was detected using RT-PCR, and the resultant sequences were subjected to genotype determination and phylogenetic analysis. [Results] Based on VP6 gene detection, 6 tested positive for bovine rotavirus, yielding an infection rate of 12.00% （6/50）. Sequence analysis of the VP7 gene from the six positive samples revealed two genotypes: G6 （n=4） and G8 （n=2）. Analysis of the VP4 gene indicated that all 6 positive samples belonged to the P[5] type. Consequently, two bovine rotavirus genotypes were identified at the dairy farm, namely G6P[5] （n=4） and G8P[5]（n=2）. Phylogenetic analysis demonstrated that the G6 genotype was closely related to bovine rotavirus strains from Turkey, whereas the G8 genotype showed closer genetic proximity to human rotavirus strains from Japan; the P[5] genotype was most similar to bovine rotavirus strains from Iran. [Conclusion] The bovine rotavirus detected in the calves of this dairy farm exhibits considerable genetic diversity, with the G6P[5] genotype being predominant. The study is the first to report the presence of the G8P[5] genotype in bovine rotavirus in the Kashgar region of Xinjiang, thereby providing valuable insights for the prevention and control of bovine rotavirus infections in southern Xinjiang.

[Objective] To investigate the effects of 4-octylitaconic acid （4-OI） on liver regeneration and inflammatory response following partial hepatectomy in rats. [Methods] Thirty healthy male Sprague-Dawley （SD） rats were randomly allocated into five groups：a sham group, a model group, and three 4-OI intervention groups （low, medium, and high dose）. The sham group underwent laparotomy with liver lobe manipulation only, whereas the model group and the 4-OI intervention groups were subjected to a 70% hepatectomy. The 4-OI intervention groups received intraperitoneal injections of 4-OI at doses of 1, 3 and 6 mg/（kg·d）, respectively, administered for three consecutive days prior to surgery , immediately post-surgery, and on the first day after surgery. Liver tissues were harvested from each group for weighing, and the liver regeneration rate was calculated. Histological assessment was performed using hematoxylin and eosin （HE） staining to evaluate morphological changes in the liver tissue. Immunohistochemical analysis was conducted to detect the expression of Ki-67 and proliferating cell nuclear antigen （PCNA）. Additionally, real-time quantitative PCR was utilized to measure the mRNA expression levels of hepatocyte growth factor （HGF）, vascular endothelial growth factor （VEGF）, tumor necrosis factor-α （TNF-α）, inter-leukin-1β （IL-1β）, interleukin-6 （IL-6）, and interleukin-10 （IL-10） in the liver tissues. [Results] The model group exhibited significantly exacerbated histopathological damage in the liver tissue compared to the sham-operated group. The mRNA expression levels of HGF, VEGF, TNF-α, IL-1β, and IL-6 were highly significantly （P<0.01） elevated, whereas the mRNA expression level of IL-10 was highly significantly （P<0.01） reduced. The average optical density value of Ki-67-positive cells was highly significantly （P<0.01） increased, while the average optical density value of PCNA-positive cells showed a non-significant（P>0.05） increase. In contrast to the model group, the 4-OI low-dose intervention groups highly significantly （P<0.01） upregulated the mRNA expression levels of HGF and VEGF, along with highly significantly （P<0.01） elevated the average optical density values of Ki-67 and PCNA-positive cells. Furthermore, 4-OI significantly reduced the mRNA expression levels of TNF-α, IL-1β, and IL-6, while significantly increasing the mRNA expression level of IL-10 （0.01<P<0.05）. [Conclusion] 4-OI exerts a protective effect on liver resection injury in rats by promoting the regeneration of the residual liver and attenuating the inflammatory response.

Plant polysaccharides are high-molecular-weight polymers composed of multiple monosaccharide units linked via glycosidic bonds. They are widely distributed in plant roots, stems, leaves, and fruits, and possess a broad spectrum of biological activities, including antimicrobial, antiviral, antitumor, immunomodulatory, hypoglycemic, and hypolipidemic effects. Owing to their structural diversity and high stability, plant polysaccharides exhibit great potential for application in the fields of medicine, food, cosmetics, and animal feed. This review systematically summarizes the molecular characteristics, extraction methods, and bioactivities of plant polysaccharides, as well as their advancements in applications across the pharmaceutical, food, cosmetic, and feed sectors. The aim is to promote the in-depth application of plant polysaccharides in diverse fields, enhance the efficient use of plant resources, and support the sustainable development of related industries.

In the context of global climate change, extreme drought has been proven to pose significant impacts on the structure and function of ecosystems, especially on soil and vegetation characteristics. However, the impact level of extreme drought on ecosystems largely varied due to the ecosystem types. The grassland ecosystem is the largest terrestrial ecosystem in China, undertaking the prominent responsibility of economic and ecological sustainable development in pastoral areas. It is highly vulnerable to changes in precipitation patterns. Therefore, assessing the response of grassland soil and vegetation characteristics to extreme drought is of great significance for understanding the evolution laws of natural ecosystems, as well as preventing and reducing the losses resulting from future extreme climate events in the ecological environment and economic development. This paper reviews the research progress on the response of grassland ecosystems to extreme drought in the aspects of soil moisture, temperature, nutrients, mineralization and microorganisms, as well as vegetation community characteristics, vegetation phenology and functional traits, in hoping to provide references for investigating the selection and adaptation of grassland ecosystems to extreme drought climate under global climate change conditions.

[Objective] To amplify the leukotoxin A （LktA） genes from the A1 and A2 serotypes of ovine-derived Mannheimia haemolytica, and construct eukaryotic expression vectors for the LktA proteins of these two serotypes. [Methods] Genomic DNA extracted from A1 and A2 serotype strains was used as the templates for PCR amplification of the LktA gene with specifically designed primers. The amplified LktA genes from both serotypes were cloned into the eukaryotic expression vector Morange2-C1 to construct recombinant eukaryotic expression vectors for the LktA proteins of A1 and A2 serotypes. Recombinant plasmids were verified by double digestion with restriction enzymes EcoRⅠand KpnⅠ and sequencing. The correctly constructed vectors were transfected into 293T cells using a liposome-mediated transfection method. After 48 hours of transfection, total cellular proteins were extracted and identified by Western blotting using an anti-mOrange monoclonal antibody as the primary antibody and goat anti-mouse IgG as the secondary antibody. Additionally, subcellular localization of the target protein was observed using laser confocal microscopy. [Results] The LktA genes of the two strains were successfully amplified by PCR using genomic DNA of A1 and A2 serotype M. haemolytica as templates, with PCR products showing clears band of approximately 2 862 bp on agarose gel electrophoresis, consistent with the expected fragment size. Double digestion of the recombinant eukaryotic expression vectors with EcoRⅠand KpnⅠ produced two distinct bands, with the fragment sizes in agreement with the expected sizes of the target insert and linearized vector. Sequencing of the recombinant plasmid after double-enzyme digestion revealed 100% identity between the obtained sequences and the designed reference sequence, confirming the successful construction of the recombinant expression vector. Cell transfection and Western blotting results showed that the eukaryotic expression vectors Morange2-C1-LktA1 （A1 serotype） and Morange2-C1-LktA2 （A2 serotype） successfully expressed LktA proteins in 293T cells, with specific target bands observed at approximately 130 kDa. Confocal microscopy demonstrated that both LktA proteins were localized to the cell membrane. [Conclusion] Eukaryotic expression vectors for LktA proteins from A1 and A2 serotypes of the ovine-derived M. haemolytica were successfully constructed, and their subcellular localization was determined. These findings provide a valuable basis for further investigation into the molecular mechanisms of LktA interaction with host cell receptors.

Bovine coronavirus （BCoV） is an important causative agent of diarrhea and respiratory infection in calves as well as winter diarrhea in adult cattle, which is prevalent in many countries and territories around the world, bringing huge economic loss to cattle farming. Currently, the available vaccines and drugs against BCoV infection is very limited. Accordingly, it is of great significance to research and develop the rapid detection methods for the early warning and effective control of BCoV infection. This paper reviewed the basic principles, application status as well as advantages and disadvantages of the main detection methods for BCoV, in hoping to provide references for the development and application of novel BCoV detection methods and the improvement of BCoV infection control.

[Objective] This study was conducted to optimize the glycosylation reaction conditions for flaxseed gum （FSG） and zein, and to characterize the structural and functional properties of the glycosylation product. [Method] Using grafting degree as the evaluation index, the main factors affecting the glycosylation reaction between FSG and zein were optimized by orthogonal test on the basis of one-way test. The structure of the FSG-zein glycosylation product was analyzed by the techniques of scanning electron microscope, Fourier infrared spectroscopy and endogenous fluorescence spectroscopy. Furthermore, the FSG-zein glycosylation product was functionally evaluated in terms of anti-oxidant capacity as well as emulsifying and foaming properties. [Result] The optimized glycosylation reaction conditions for FSG and zein were as follows: the ratio of zein solution to FSG solution was 1︰3, the pH value of the reaction system was 2, the reaction temperature was 90 ℃, and the reaction duration was 90 min. Under these conditions, the grafting degree of the FSG-zein glycosylation product was 77.81%. Scanning electron microscope, Fourier infrared spectroscopy and endogenous fluorescence spectroscopy analyses demonstrated that the initial structures of FSG and zein were significantly changed after the glycosylation reaction, confirming that FSG and zein generated FSG-zein glycosylation compound by glycosylation reaction. At a concentration of 1 mg/mL, the FSG-zein glycosylation product possessed a significantly （P<0.05） higher scavenging rate of ·OH than FSG, and exhibited significantly （P<0.05） elevated scavenging rate of DPPH and ABTS⁺ radical as well as total reducing power than FSG and zein. Significantly （P<0.05） increased emulsifying activity index and stability index as well as significantly （P<0.05） improved foaming ability and stability were observed in the FSG-zein glycosylation product in comparison to FSG and zein. [Conclusion] The glycosylation reaction conditions for FSG and zein were optimized, and the obtained glycosylation product possessed good anti-oxidant capacity as well as emulsifying and foaming abilities.

[Objective] To investigate the effects of dietary supplementation with Enteromorpha polysaccharide-iron （EP-Fe） during late gestation on intestinal microbiota and iron metabolism in sows. [Methods] Sixty primiparous Landrace × Yorkshire crossbred sows at （90±2） d of gestation with similar body condition, expected farrowing date, and breeding sire were randomly allocated into two groups （30 sows per group, one sow per replicate）. The control group received a basal diet, while the EP-Fe group was fed the basal diet supplemented with 140 mg/kg EP-Fe from gestational day 95 until parturition. Fresh fecal samples from gestational day 112 and serum from farrowed sows were collected to analyze serum biochemical parameters, fecal microbial richness and diversity and fecal short-chain fatty acids （SCFAs） content. [Results] Dietary EP-Fe supplementation increased serum triglyceride （TG） and albumin （ALB） in sows. EP-Fe markedly altered the fecal microbial composition, elevated the relative abundance of Christensenellaceae_R-7_group, Oscillibacter, Prevotellaceae_NK3B31_group, UCG-002, Clostridium_sensu_stricto_1 and unclassified_f__Prevotell-aceae, while reducing UCG-008 and norank_f__norank_ o__Gastranaerophilales. A tendency toward an increase in fecal SCFA concentrations was also observed. EP-Fe supplementation enhanced the relative abundance of Lachnospiraceae_XPB1014_group, which was positively correlated with fecal iron, and decreased norank_f_ norank_ o_Clostridia_UCG-014, which was negatively correlated with placental iron transport genes. These changes reduced fecal iron, upregulated placental iron transporter gene expression, and enhanced iron absorption, utilization and transport in sows. [Conclusion] EP-Fe supplementation can modify the gut microbiota composition, increase SCFAs content, enhance intestinal iron absorption, and promote iron metabolic transfer between sows and piglets.