[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.

[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 investigate the effects of Apocynum venetum water extract （AVWE） on gastrointestinal motility in mice and provide a scientific reference for the rational use of Apocynum venetum-based products. [Methods] A two-fold increasing concentration test, single-concentration test, and combined administration with a muscarinic receptor （M-receptor） agonist were conducted to evaluate the effects of AVWE on isolated small intestinal segments in mice. Mice were intragastrically administered 5, 25, 125 g/L AVWE or saline, followed by ink suspension, to calculate intestinal propulsion rates and ink retention rates in four equally divided segments of the small intestine. [Results] Compared with pre-treatment values, two-fold increasing concentrations of AVWE （0.5-8.0 g/L） could reduce the contractile tension and amplitude of isolated intestine. A single concentration of AVWE （4.0 g/L） highly significantly （P<0.01） decreased contractile tension and amplitude to （74.5±2.2）% and （82.0±2.6）% of pre-treatment levels, respectively. The peak contraction percentage of intestine treated with AVWE combined with the M-receptor agonist bethanechol chloride （BCh） [（180.8±6.4）%] was extremely significantly （P<0.01） higher than that with Tyrode’s solution combined with BCh [（158.1±4.7）%]. AVWE administration dose-dependently reduced intestinal propulsion rate, with ink predominantly retained in the third part of the small intestine. [Conclusion] AVWE inhibits gastrointestinal motility in mice, and its suppressive effect on intestinal motility may be independent of M-receptor antagonism.

[Objective] To explore the effect of different solid-state fermentation techniques of lactic acid bacteria （LAB） on the bioavailability of active components of Astragalus membranaceus （AM） and evaluate its safety. [Methods] AM powder was fermented anaerobically using seven LAB strains （ZW0410,FJ0021,LYS0032,BJLY0086,SS0204,WT0327,GL0108） under raw material conditions （substrate∶water=1∶0.5, 2% inoculum, 37 ℃ for 48 h）. Parameters including pH, microbial activity （LAB count）, lactic acid content and functional components （total flavonoids, crude polysaccharides, total sugars） were measured to screen optimal LAB strains. [Results] Six LAB strains （ZW0410, FJ0021, LYS0032, BJLY0086, SS0204, WT0327） could ferment AM. After fermentation, the number of LAB could reach more than 10⁸ CFU/g, and the lactic acid content was significantly （P<0.05） higher than that of the control group. The ZW0410 group showed the best effect. The number of LAB reached 2.64×10⁹ CFU/g, lactic acid content was 14.84 g/kg, pH decreased to 4.12, total flavonoids and crude polysaccharides increased to 18.06 g/kg （1.65 times higher than the blank group） and 36.93 g/kg, respectively, and total sugar content decreased by 6.4 percentage points. The Lactic acid bacteria BJLY0086 group showed the highest total flavonoid content（19.48 g/kg, 1.86 times higher than the blank group）. In addition, LAB fermentation significantly inhibited mold proliferation （No mold was detected except GL0108 group）, while mycotoxins aflatoxin B₁ （AFB₁）, zearalenone （ZEN）, deoxynivalenol （DON） and Escherichia coli remained within safe limits. [Conclusion] Under the conditions of this experiment, Lactobacillus plantarum ZW0410 was identified as the optimal strain for AM fermentation. Using this lactic acid bacterium to ferment AM, the content of total flavonoids and crude polysaccharides could be significantly （P<0.05） improved, and the growth of mold could be inhibited.

[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 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.

[Objective] To address the industrial challenges of high production costs and low biomass in feed-grade Saccharomyces cerevisiae. [Methods] The indigenous low-activity strain SCL6 was selected as the research subject, and fermentation process optimization was conducted based on YPD medium. A two-stage optimization strategy was implemented. First, key medium components （carbon source, nitrogen source, inorganic salts） were screened through single-factor experiments, and the key factors affecting the fermentation process were screened by Plackett-Burman test. Subsequently, a Box-Behnken central composite design combined with response surface methodology （RSM） was employed to construct a mathematical model for multi-factor interactions. Parameter optimization and model validation were performed using Design-Expert software. Biomass was quantified via OD₆₀₀ measurements coupled with wet weight determination. Key influential factors were identified via analysis of variance （ANOVA）. Finally, the optimized process was conducted in a 3 L fermenter with dynamic feeding and parameter control. [Results] ①Factor significance analysis：carbon source type, cultivation temperature and initial pH exhibited highly significant （P<0.01） impacts on biomass accumulation, identifying them as primary limiting factors. Nitrogen composition, inorganic salt concentration and inoculum size showed no significant （P>0.05） effects. ②Optimized parameters：maltose （50.46 g/L） as carbon source, corn steep liquor （20 g/L） as complex nitrogen source, trace elements （MgSO₄·7H₂O 4 g/L, ZnSO₄ 0.1 g/L, KH₂PO₄ 2 g/L）, initial pH 6.10, and dynamic temperature control （29.52 ℃）. ③Process validation：in 3 L fermenters, SCL6 achieved an OD_{600 nm} of 106.8, cell wet weight of 150.2 g/L, representing 2.33-fold and 5.34-fold improvements over optimized flask culture （OD_{600 nm}=46.6） and original flask culture （OD_{600 nm}=20）, respectively. The viable cell count reached 2.1×10⁹ CFU/mL, complying with GB/T 22547—2008 feed additive standards. ④Economic evaluation：the optimized process reduced production costs by 35.8% per ton of culture, including 29.9% savings in carbon source expenditure and 42.5% reduction in energy consumption, effectively resolving inefficiencies in glucose utilization and excessive energy demand for temperature control in conventional processes. [Conclusion] The two-stage fermentation optimization process based on the response surface methodology established in this study has significantly improved the industrial cultivation efficiency of the indigenous Saccharomyces cerevisiae SCL6. By accurately identifying the key limiting factors and establishing a dynamic regulation model, an exponential increase in the biomass of the yeast cells and a significant reduction in the production cost have been achieved.

Sandy shrubs have a unique appearance and developed root systems, with characteristics such as tolerance to poor soil fertility, drought resistance, and cold resistance. They play a good ecological role in soil improvement, windbreak and sand fixation, and can be developed and utilized in a wide range of fields. They have ecological value, landscape value, and economic value, and are an important component of arid and semi-arid ecosystems. Inner Mongolia is rich in sandy shrubs resources, with various Chinese endemic sandy shrubs.In recent years, according to the concept of sustainable development, the development and utilization of sandy shrubs has been continuously deepened. This article briefly introduced the distribution, types, and application value of sandy shrubs in Inner Mongolia, and summarized the development and utilization of sandy shrubs in multiple fields such as wood, paper, feed, medicine, and bioenergy. It provided a basis and ideas for further strengthening the development and utilization of sandy shrubs resources in the future. It should expand the application fields of sandy shrubs through scientific planning, improving development and utilization methods, so as to promote sustainable utilization of sandy shrubs, and realize the coordinated development of ecological protection and economic benefits.

[Objective] To systematically assess the nutrient composition characteristics of ground source protein feed resources in Zhejiang Province, and to accumulate data for the establishment of a database of ground source protein resources, soybean meal reduction and substitution actions and feed industry optimization in Zhejiang Province. [Methods] Fourteen kinds of ground source protein feedstuffs from Zhejiang Province were collected, and the resource characteristics were analyzed by determining the nutrient compositions of crude protein, crude fiber, and amino acid, combined with the analysis of variance （ANOVA） and correlation statistics. [Results] Crude protein content：rice bran meal was the lowest [（5.69±1.82）%], feather meal was the highest [（81.48±4.36）%], and defatted rice bran was the medium [（14.61±1.15）%]; crude fiber content：fish meal was the lowest [（2.70±1.28）%], rice bran meal was the highest [（26.97±15.14）%], and defatted rice bran was the medium [（8.91±0.66）%]. The crude fiber content of defatted rice bran showed significant difference （P<0.05） with rice bran meal and peanut meal; total amino acids content：rice bran meal was the lowest [（4.38±1.74）%], feather meal was the highest [（77.03±3.80）%], and defatted rice bran was medium [（11.86±1.06）%], and the total amino acid content of defatted rice bran was not significantly different （P>0.05） with wine lees, rice bran meal and wheat bran, and the difference with other varieties was significant （P<0.05）. There was a highly significant （P<0.01） negative correlation between crude protein content and crude fiber content, indicating that feedstuffs with higher protein content usually have lower fiber content; there was a highly significant （P<0.01） positive correlation between crude protein content and total amino acid content, indicating that feedstuffs with higher protein content contain higher amino acids. There was a highly significant （P<0.01） negative correlationbetween crude fiber content and total amino acids content, and a significant （P<0.05） negative correlation between crude fiber content and crude ash content. There was a significant （P<0.05） negative correlation between crude ash content and moisture content. [Conclusion] Defatted rice bran is an abundant ground source protein feed resource in Zhejiang Province. The effect of its high cellulose content on animal digestibility should be considered in application. Subsequently, through technological innovations such as fermentation technology, bacteria-enzyme synergy technology and low-temperature processing technology, the nutritional deficiencies of defatted rice bran are expected to be broken through, which has great development potential and application prospects.

[Objective] To screen alfalfa individual plants with superior traits and enrich the germplasm resources of high quality alfalfa in Xing’an League, Inner Mongolia. [Methods] A comprehensive evaluation was performed on 20 alfalfa individual plant materials by measuring seven agronomic traits （plant height, stem diameter, branch number, leaf length, fresh weight, dry weight and dry-to-fresh ratio） and six nutritional quality indicators （crude protein, crude fat, neutral detergent fiber, acid detergent fiber, crude ash and relative feeding value）. The comprehensive performance was systematically evaluated by membership function method. [Results] After analysis by membership function method, the best individual plant was XM-9, whose fresh weight was 160 g/plant, dry weight was 62.61 g/plant and dry-to-fresh ratio was 0.39. Its crude fat content was 8.19%, neutral detergent fiber content was 47.91%, acid detergent fiber content was 37.74%, crude protein content was 20.42%, crude ash content was 2%, relative feeding value was 115.70. Among the 20 alfalfa individual plants, the top five individual plants were XM-9, XM-3, XM-1, XM-5 and XM-15. [Conclusion] XM-9 individual plant exhibited excellent production performance and nutritional quality, and could be used as the core parental material for the construction of local high-quality alfalfa asexual family and the breeding of new alfalfa varieties, which provided an important material basis for germplasm innovation of alfalfa in Xing’an League.

Melinis repens （Willd.） Zizka is a highly stress-resistant grass species of the Poaceae family in tropical regions, which is tolerant to high temperatures, drought, and barrenness.It possesses ornamental, forage, ecological, and medicinal values, demonstrating significant application potential in tropical areas. The widespread use of Melinis repens （Willd.） Zizka for ecological slope protection and landscaping requires a substantial supply of seeds. However, seed production of Melinis repens （Willd.） Zizka faces challenges such as low seed-setting rates, inconsistent maturity periods, strong seed dormancy, and low germination rates.Therefore,based on analysis of the existing literature and combined with the research results of other forage grasses in the Poaceae family, this paper comprehensively reviewed the biological characteristics, geographical distribution, reproductive traits, seed biological properties, seed propagation techniques, and tissue culture systems of Melinis repens （Willd.） Zizka. The study summarized technical difficulties and key issues in seed propagation of Melinis repens （Willd.） Zizka, and proposed future research directions, to provide important guidance for improving seed production. Additionally, it also offered reference for the conservation and promotion of Melinis repens （Willd.） Zizka germplasm resources.

[Objective] To understand the effects of salt and alkali stress on seed germination and seedling growth of Sorghum sudanense. [Methods] With Sorghum sudanense seeds as experimental materials, one ultrapure water control group and three salt and alkali stress groups （NaCl, Na₂CO₃ and NaOH） were set up. Each group was set with 6 concentration gradients: the concentrations of the NaCl group were 50, 100, 150, 200, 250, and 300 mmol/L; the concentrations of the Na₂CO₃ group were 15, 25, 50, 75, 100, and 150 mmol/L; and the concentrations of the NaOH group were 5, 10, 15, 20, 25, and 30 mmol/L. Sorghum sudanense seeds were placed in a petri dish containing treatment solution （25 ℃ dark culture）, and the number of germination was recorded daily. At the end of the germination test, the root length, bud length, fresh weight and dry weight of the seeds were measured, and the seed germination rate, germination potential and germination index were calculated. According to the measured indicators, the critical values of salt and alkali stress of NaCl, Na₂CO₃ and NaOH on Sorghum sudanense seeds were calculated. [Results] When the NaCl concentration was greater than or equal to 100 mmol/L, the seed germination rate and germination potential were significantly （P<0.05） lower than those of the control group. When the concentration was greater than or equal to 50 mmol/L, the seedling bud length, root length, fresh weight and germination index were significantly （P<0.05） lower than those of the control group. When the concentration of Na₂CO₃ was greater than or equal to 75 mmol/L, Sorghum sudanense seeds did not germinate. When the concentration was higher than 15 mmol/L, the germination rate, germination index, bud length, root length and fresh weight were significantly （P<0.05） lower than those of the control group. Compared with the control group, there was no significant difference （P>0.05） in seed germination rate, germination potential, or dry weight among all concentration gradients of NaOH. The bud length and root length were significantly （P<0.05） lower than the control group at the concentration of 10 mmol/L. The fresh weight was significantly （P<0.05） lower than that of the control group at the concentration of 5 mmol/L. The critical concentrations of NaCl, Na₂CO₃ and NaOH for Sorghum sudanense seeds were 269.52, 49.18 and 124.76 mmol/L, respectively. The sensitivity of Sorghum sudanense seeds to salt and alkali was Na₂CO₃>NaOH>NaCl. [Conclusion] The effects of saline-alkali stress on the seed germination and seedling growth of Sorghum sudanense vary with salt types and concentrations. Among them, Na₂CO₃ has the strongest inhibitory effect, while NaCl has the weakest. Moreover, the seedling growth indices （especially fresh weight and root length） are more sensitive to saline-alkali stress than the germination indices （such as germination rate）.

[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 study on herdsmen’s perception and adaptability to extreme weather events is of great significance for improving herdsmen’s disaster resistance. [Methods] Based on the data of 194 herdsmen in central and western Inner Mongolia, the binary Probit model was used to empirically investigate the factors influencing herdsmen’s perceptions of extreme weather events and adaptive behavior. [Results] ①The factors significantly affecting herdsmen’s perception of extreme weather events included herdsmen’s education level, household labor force size, average annual family income, the number of channels for obtaining information, and the timeliness of obtaining meteorological information. The impact of whether to borrow or not was not significant. ②Household labor force size, average annual income of the family, and timeliness of meteorological information were significant factors affecting herdsmen’s adaptive behaviors to extreme weather events, whether to borrow or not and the number of channels for obtaining information also positively impacted on herdsmen’s adoption of adaptive behaviors. [Conclusion] Herders′ perception and response behaviors to extreme weather events are comprehensively influenced by multi-dimensional factors such as economic foundation, information conditions, family structure, and personal characteristics. Moreover, the impacts of different factors vary in the links of perception and response. This provides a direction for formulating targeted policies to guide herders in coping with extreme climates.

[Objective] To explore candidate genes influencing sheep growth traits and provide a basis for genetic improvement in sheep breeding. [Methods] Agarose gel electrophoresis and sequencing were used to detect the polymorphism of PPARGC1A gene InDels （insertions/deletions） in Hu sheep, Dorper sheep and Small-tailed Han sheep, and the association between the polymorphism of PPARGC1A gene and sheep growth traits was analyzed. [Results] Three genotypes （II, ID and DD） of the PPARGC1A gene were detected in all three sheep breeds. The II genotype frequencies of Hu sheep, Dorper sheep, and Small-tailed Han sheep were 0.328, 0.209 and 0.563, respectively. The ID genotype frequencies were 0.432, 0.488 and 0.406, respectively, while the DD genotype frequencies were 0.240, 0.302 and 0.031, respectively. Association analysis showed a significant association（P<0.05） between the PPARGC1A gene and body height, back height and buttock height in Hu sheep, as well as body length in Small-tailed Han sheep （P<0.05）. No significant associations were observed in Dorper sheep （P>0.05）. [Conclusion] The PPARGC1A gene had an impact on some growth traits in Hu sheep and Small-tailed Han sheep, and could be used as an important functional candidate gene for crossbreeding improvement in Hu sheep and Small-tailed Han sheep.

[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 prevalence of toxoplasmosis infection in free-range cattle in Yuxi City, Yunnan Province, and analyze the potential risk factors associated with its occurrence. [Methods] ELISA was used to detect Toxoplasma antibodies in 341 serum samples collected from free-range cattle in 9 counties （cities and districts） within Yuxi. The positive rate of Toxoplasma antibodies in free-range cattle was calculated, and the statistical differences in antibody positivity rates based on different regions, breeds, sexes, and sampling seasons were analyzed. [Results] The overall positive rate of Toxoplasma infection antibodies in free-range cattle in Yuxi was 3.23%. Significant statistical differences in antibody positivity rates were observed between different regions （χ²=22.594, P<0.05） and breeds （χ²=10.126, P<0.05）. However, no significant differences were found based on sex （χ²=0.588, P>0.05） or sampling season （χ²=6.127, P>0.05）. [Conclusion] The present investigation revealed that Toxoplasma gondii infections exist in free-range cattle across multiple regions of Yuxi City, with geographical location and cattle breed identified as the primary influencing factors. Future research should further explore the specific factors influencing Toxoplasma antibody positivity rates in free-range cattle of different regions and breeds, and enhance monitoring and control measures in high-risk areas and breeds to reduce the risk of toxoplasmosis, ensuring the health of the cattle population and the economic benefits of farming.

[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.