In recent years, gene editing technology has been widely adopted due to its capability for precise and efficient modification of genetic information. By introducing disease-resistant genes or knocking out host genes essential for pathogen infection, this technology can effectively confer resistance to specific infectious diseases in animals, accelerating the development of new livestock and poultry breeds with enhanced disease resistance. Under the threat of major epidemics such as African swine fever (ASF), there is an urgent need not only to continuously strengthen conventional disease prevention and control measures but also to improve the innate disease resistance of livestock and poultry through genetic breeding. Therefore, cultivating breeds with high-efficiency disease resistance has become a pressing demand and core mission in current animal husbandry research and industrial practices. This paper reviews the current applications of gene editing technology in disease-resistant breeding of livestock and poultry, and prospectively outlines potential future directions and key research areas that warrant focused exploration.

In the process of livestock and poultry farming and breeding, it is necessary to detect the body composition of individual livestock and poultry in different growth periods to analyze their growth conditions, but there is a lack of methods to measure the body composition of livestock and poultry accurately in the process of farming. Bioelectrical impedance analysis of the composition of biological tissues has the advantages of low price, simple operation, non-invasive and harmless, and has a good application prospect in the measurement of body composition and meat quality testing of livestock and poultry. This paper summarizes and analyses the research progress of bioelectrical impedance, focusing on the measurement electrodes and their distribution, the technological progress of bioelectrical impedance measurement system, and the accuracy of measurement of body composition in livestock and poultry. It summarizes the shortcomings of the current bioelectrical impedance technology, looks forward to the future research direction of the measuring electrodes and bioelectrical impedance measurement system, and puts forward the prospect of the application of bioelectrical impedance technology in the intelligent animal husbandry industry.

China has a rich diversity of chicken breeds with 140 native breeds, which harbor numerous excellent genetic traits. The conservation, breeding, and utilization of chicken genetic resources are of significant importance for promoting the independent development of national chicken breeding industry. The ultra-low temperature cryopreservation of semen is one of the most practical techniques for the long-term preservation and efficient utilization of livestock and poultry genetic resources. The semen cryopreservation technology for livestock, particularly for cattle, is relatively well-developed, but the technology was limited in chicken due to the long tails and small heads of spermatozoa, which result in poor freeze resistance. The poor fertility and sustained fertilization ability of chicken frozen sperm limited the application of semen cryopreservation technique in conservation and breeding. Post-translational modification of proteins was an important regulatory pathway through which cells respond to internal and external environmental stimuli. In mature sperm, both transcription and translation activities were largely halted, lysine acetylation modification of proteins might play crucial roles during the cryopreservation of chicken semen. These modifications could be essential for maintaining sperm structural integrity, mitochondrial function stability, and DNA integrity. However, the specific mechanisms underlying these effects remain unclear. This review aimed to provide a reference for investigating the role of lysine acetylation in the cryopreservation of chicken semen and establishing novel cryopreservation methods, and to offer theoretical insights and technical support for the efficient conservation of poultry genetic resources.

High-throughput single-cell sequencing technology has become an important tool for analyzing the composition information of different cells. Through this technology, the genetic characteristics of sample cells can be analyzed with high precision, revealing the gene structure and expression status of cells in complex samples, and reflecting the heterogeneity between cells. This paper summarizes the research results of single-cell sequencing technology on the development mechanism of different types of ovarian cells in the process of sheep ovarian growth and development.The use of single-cell sequencing technology can provide a more comprehensive understanding of the molecular characteristics, functional differences, and intercellular interactions of different cell types in sheep ovaries, providing new ideas and methods for in-depth research on the physiological functions of sheep ovaries and the diagnosis and treatment of related diseases.

The study of luteal function in dairy cows is of great importance for improving reproductive efficiency. In recent years, despite advancements in dairy production technology, pregnancy rates remain limited by factors such as embryo loss and luteal insufficiency. As a critical temporary organ for pregnancy maintenance, the function of the corpus luteum directly affects reproductive outcomes. An in-depth understanding of the physiological characteristics, formation, and degradation mechanisms of the corpus luteum is essential for reproductive management in dairy cows. This review summarizes the mechanisms of corpus luteum formation and degradation, internal and external factors influencing its function, and related interventions, with a focus on the application of hormonal regulation and biotechnology in maintaining luteal function. The aim is to provide theoretical insights for improving corpus luteum function and enhancing reproductive efficiency.

Anaerobic fungi play a key role in the digestive tract of herbivores, especially in the decomposition and transformation of lignocellulose. These microorganisms, through their unique structure and function, efficiently break down stubborn plant fibers to meet the nutritional and energy needs of their host animals. In addition, the interaction between anaerobic fungi and other microorganisms not only helps to maintain the environmental balance in the gut, but also improves the efficiency of energy recovery, showing its potential importance in the field of ecology and bioenergy. In this paper, the biological and functional characteristics of anaerobic fungi in digestive tract and their interactions with other microorganisms are discussed in detail, aiming to provide ideas for the utilization of anaerobic fungi in sustainable agriculture and renewable energy development.

Flavonoids are compounds characterized by a C6-C3-C6 basic skeleton, consisting of two benzene rings connected by three carbon atoms. They can be categorized into various subclasses, such as flavonoids and anthocyanins. These compounds exhibit numerous biological effects, including antibacterial, anti-inflammatory, antioxidant, and immune-boosting activities. However, flavonoids face challenges such as low solubility, poor stability, limited permeability, and low bioavailability due to their chemical composition. With the advancement and maturation of nanotechnology, nanoparticles derived from natural macromolecular substances have significantly improved the solubility and biological functions of flavonoids. This paper integrates and summarizes the research on flavonoid nanoparticles, elucidating their mechanisms of action and providing a theoretical basis for their development and application in animal production.

The bacterial two-component system (TCS) is a widespread signaling transduction pathway in organisms, which can sense and respond to physical, chemical, and biological stimuli inside and outside the cell, and induce a series of cellular responses through coupled sensing and regulatory mechanisms.TCS is the principal mechanism for bacteria to sense and respond to environmental signals and regulate physiological behaviors, which plays a crucial role in bacterial drug resistance, pathogenicity, biofilm formation, virulence factor regulation, etc.TCS regulates gene expression and cellular behaviors through the interactions of the two components (sensors and effectors) to handle the impact of adverse environment on bacteria, therefore achieving the goal of proliferation and invasion of the host.This paper reviews the research advances in the structure, function, drug resistance regulation and pathogenicity, and inhibitors of the two-component system, providing a reference for the development of novel antimicrobial drugs and bacterial prevention and control.

Dicrocoeliasis is a parasitic disease caused by Dicrocoelium dendriticum, which primarily infects the hepatic bile duct and gallbladder of ruminants such as cattle and sheep. Infected animals exhibit clinical signs including weight loss, lethargy, anorexia, diarrhea, and other progressive debilitating symptoms that can ultimately lead to mortality due to the aggravation of infection. At present, there is no long-term safe vaccine available, and the escalating issue of global drug resistance poses significant threats to public health while incurring substantial economic losses. Effective prevention and control strategies rely on early detection, precise diagnosis, judicious deworming protocols, regular monitoring for drug resistance, and comprehensive epidemiological investigations. This paper reviews advancements in detection technologies and preventive measures for dicrocoeliasis over the past three decades; it critically compares the strengths and limitations of etiological, serological, and molecular biological detection methods while elucidating the clinical adverse reactions associated with commonly used anti-dicrocoeliasis medications. The objective is to provide a scientific foundation for future research into novel micro-detection technologies as well as enhancements in comprehensive prevention strategies.

Psoroptic mange, a prevalent ecto-parasitic disease affecting domestic and wild animals globally, is primarily characterized by skin lesions. Understanding the characteristics and mechanisms underlying these skin lesions is crucial for developing novel measures against psoroptic mange. This paper systematically reviews the pathological manifestations of skin lesions in psoroptic mange, focusing on the perturbations in the skin's physical and immune barriers during disease progression. Potential factors contributing to these alterationss are discussed, including the mechanical activity of Psoroptes mites and their excretory-secretory proteins (PsoES) which can impair the skin 's physical barrier. Additionally, allergenic and other bioactive molecules within the PsoES can infiltrate the weakened physical barrier, disrupting the immune barrier and thereby accelerating the onset and and progression of skin damage. The objective of this review is to provide insights and directional guidance for the development of novel anti-mite therapeutics, ultimately aiming to provide new perfectives on the prevention and control of psoropic mange.

The study aimed to explore the competitive binding and targeting relationship between TCONS_00056481, IRS1 and miR-660. The porcine subcutaneous preadipocytes were isolated and cultured, the expression levels of TCONS_00056481, miR-660 and IRS1 in the backfat tissues of Anqing Six-end-white pigs (fat type) and Large White pigs (lean type) and their temporal expression changes during porcine preadipocytes differentiation were detected by RT-qPCR, the expression levels of IRS1 protein in the backfat of the two pig breeds was detected by Western blot, and the targeted binding relationship between TCONS_00056481, IRS1and miR-660 were identified by dual luciferase reporter gene detection system in this study. The results showed that the expression levels of IRS1, miR-660 and TCONS_00056481 in the backfat of the two pig breeds were significantly different (P < 0.01), and the expression levels of IRS1, miR-660 and TCONS_00056481 were significantly different during the differentiation of porcine preadipocytes, indicating that IRS1, miR-660 and TCONS_00056481 had potential regulatory roles in pig fat deposition and porcine preadipocyte differentiation. The dual luciferase activity of co-transfected TCONS_00056481 wild-type vector and miR-660 mimics was significantly lower than that of its control group (P < 0.01), and the dual luciferase activity of co-transfected IRS1 wild-type vector and miR-660 mimics was significantly lower than that of its control group (P < 0.01); the dual luciferase activity of co-transfected TCONS_00056481/IRS1 mutant vector and miR-660 mimics was not significantly different from that of the control group (P>0.05), indicating that miR-660 could regulate IRS1 and TCONS_00056481 through binding sites. The study preliminarily verified that lncRNA TCONS_00056481 can competitively bind to miR-660 to regulate the expression of IRS1; IRS1, TCONS_00056481 and miR-660 can be used as candidate gene pairs of competing endogenous RNA molecules in regulating porcine lipid formation for further study.

This study aimed to reveal the genetic structural characteristics of sheep populations with different wool types and screen candidate genes related to wool traits through selection signatures analysis. The sheep populations were divided into two groups based on different wool types, including 59 fine wool sheep and 48 coarse wool sheep.Genotyping of 8 sheep populations (15 Oula sheep, 13 Tashkurgan sheep, 15 Altay sheep, 16 Zangxi sheep, 12 Qinghai wool-mutton type sheep, 10 Gansu Alpine Merino, 15 Chinese Merino, 11 Aohan Merino) was performed using a self-developed ovine SNP 50K liquid chip, followed by principal component analysis, neighbor-joining tree, and population genetic structure analysis after quality control. Candidate genes associated with wool trait were screened based on two selection signal methods: population genetic differentiation index (F_ST) and nucleotide diversity ratio (θ_π ratio). The functions of the candidate genes were determined through KEGG pathway enrichment analysis. The results of principal component analysis, neighbor-joining tree, and population genetic structure analysis indicated the presence of genetic differentiation between the two groups of sheep populations. Based on the combined analysis of F_ST and θ_π ratio, the top 1% regions were identified as selected regions, 165 selected regions and 456 selected genes were identified. Several selected genes were identified that are closely associated with hair follicle development and hair growth (JAK2, SELENBP1), melanin synthesis (IRF4), the indirect regulation of dermal papilla cells (RAC2), and a key housekeeping gene in skin molecular biology (SDHA) through gene annotation. This study explored the genetic structure of 8 Chinese sheep populations with clear population differentiation between fine-wool and coarse-wool sheep groups. Selection signature analysis identified candidate genes associated with wool trait, such as JAK2, IRF4, RAC2, IDUA, SDHA and SELENBP1. This study will provide a reference for the molecular genetic marker discovery of wool trait in sheep.

The study aimed to conduct an in-depth analysis of the slaughtering performance, production performance, edible quality, nutritional quality, and flavor compounds of various parts of the Ujumqin sheep, this study systematically evaluated the quality characteristics of different sections of the Ujumqin sheep. The findings provide a valuable reference for optimizing and utilizing the resources of the Ujumqin sheep. Sixty healthy 6-month-old Ujumqin lambs, raised under identical growth conditions, were selected for this study. Their pre-slaughter live weight averaged (33.84±3.22) kg. After slaughter, the slaughtering performance, carcass index, and meat quality were assessed. The nutritional values of the longissimus dorsi muscle (LD) and biceps femoris muscle (BF) were assessed and analyzed using a fully automatic amino acid analyzer (LA8090) and gas chromatography-mass spectrometry (GC-MS5977B). Each measurement was replicated 3 times to ensure accuracy and reliability. The results demonstrated that the average pre-slaughter live weight of 6-month-old Ujumqin sheep was (33.84±3.22) kg, with an average carcass weight of (14.69±1.77) kg and a slaughter rate of (45.17±2.64)%. Regarding meat quality, the water loss rate of BF was significantly lower than that of LD ((3.77±0.15)% vs. (5.18±0.19)%, P < 0.05). The crude protein content of BF was also significantly lower than that of LD ((19.66±0.61)% vs. (20.00±0.78)%, P < 0.05), while the shear force of BF was significantly higher than that of LD ((61.14±8.88) N vs. (55.57±12.57) N, P < 0.05). In terms of color, there was no significant difference in L^* values between the two muscles; however, the a^* value of LD was significantly lower than that of BF, and the b^* value of LD was significantly higher than that of BF (P < 0.05). Regarding texture characteristics, the hardness of BF was significantly lower than that of LD ((78.18±18.74) N vs. (85.90±23.95) N, P < 0.05). In terms of nutritional value, the amino acid content and fatty acid composition of BF were significantly superior to those of LD (P < 0.05), particularly in essential amino acids such as lysine, non-essential amino acids such as glutamic acid and aspartic acid, and unsaturated fatty acids such as oleic acid, alpha-linolenic acid, docosahexaenoic acid, and arachidonic acid. The biceps femoris muscle of Ujumqin sheep exhibits superior meat quality and nutritional value compared to the longissimus dorsi muscle. Its rich composition of essential amino acids and fatty acids, along with a more favorable n-6:n-3 ratio, highlights its higher nutritional value.

The aim of this study was to investigate the regulatory effect of protein kinase D1 (PRKD1) gene, an important candidate gene for chest depth trait in beef carcass, on the osteogenic differentiation of bovine osteoblasts. In this study, osteoblasts derived from pregnancy Huaxi bovine fetal ribs with 3 months old were used as in vitro models. According to PRKD1 gene sequence, PRKD1 overexpressed plasmid (pPRKD1) and PRKD1 siRNA (siPRKD1) were constructed and synthesized, respectively, and transfected into bovine osteoblasts. On the 4 days of differentiation, RT-qPCR and Western blot assay were used to detect the expression levels of RUNX2, SP7, SPP1 and COL I genes. The activity of ALP was detected on the 7 days of differentiation. On the 21 days of differentiation, the osteogenic ability of osteoblasts was detected by Alizarin Red calcium nodule staining. All the above-mentioned experiments were conducted with 3 biological replicates each, and within each group, 3 intra-group replicates were set up. The results showed that after overexpression of PRKD1, mRNA and protein expressions of SP7 and COL I genes were significantly increased(P < 0.01), while RUNX2 and SPP1 genes were not significantly changed, PRKD1 overexpression also significantly increased the ALP activity and mineralized nodules of osteoblasts, while interference of PRKD1 showed the opposite effect. In conclusion, PRKD1 gene significantly affects the differentiation and osteogenic function of bovine rib osteoblasts, and the results provide theoretical basis for further analysis of the regulation mechanism of PRKD1 gene on bovine carcass chest depth traits.

This study aimed to explore the phylogenetic relationships between the Jinggang black-palm goose (JGG) and various local goose breeds across China based on whole-genome SNP data, and to analyze the genetic diversity and genetic structure of Chinese geese and JGG, providing a theoretical foundation for the identification and conservation of Chinese goose resources. Genome resequencing data (12×coverage) from 81 Jinggang black-palm geese and 120 individuals of 6 local goose breeds were analyzed. Single nucleotide polymorphisms (SNPs) detection and annotation were conducted on autosomal regions using GATK and SnpEff softwares. A neighbor-joining (NJ) tree, principal component analysis (PCA), and Admixture analysis were performed to assess their population structure and genetic diversity. The JGG population harbored 5 955 261 SNPs, predominantly in intergenic (46.39%) and intronic regions (34.56%), with fewer in exonic regions (1.38%). Consistently, NJ tree, PCA, and Admixture analyses revealed distinct clustering of JGG, showing closer genetic affinity to Xingguo grey geese, Fengcheng grey geese, and Lionhead goose, driven by geographic isolation and artificial selection for body size and plumage traits. JGG exhibited low genetic diversity, with 3 414 168 common SNPs. Key parameters included: proportion of polymorphic sites (Pn=0.83), expected heterozygosity (He=0.26), observed heterozygosity (Ho=0.23), inbreeding coefficient (F=0.33±0.09), intra-population genetic distance (DST=0.224±0.022), and runs of homozygosity (ROH=12.87±8.27). This study systematically elucidates the population genetic structure and genomic characteristics of Chinese geese and JGG. As an independent local breed, JGG's genetic differentiation is shaped by geographic isolation and phenotypic selection, yet its low genetic diversity poses a risk of trait loss, highlighting the imperative for enhanced conservation and utilization efforts.

This study aimed to explore the relationship between adenosine monophosphate-activated protein kinase (AMPK), especially mitochondrial AMPK (mAMPK), and the formation of fatty liver in goose. In this study, 12 healthy 70-day-old male Landes goose were randomly divided into a control group (normal liver group) fed ad libitum and a overfed group (fatty liver group) for in vivo experiments. The main isoforms of AMPKα, its subcellular distribution, and the protein content of AMPKα1 in whole-cell and mitochondrial lysates of normal and fatty livers were detected by Western blotting and immunofluorescence techniques. Goose primary hepatocytes were treated with high concentrations of glucose or palmitic acid, and the protein content of AMPKα1 in the control group, 100 mmol·L^-1 glucose group, and 0.5 mmol·L^-1 palmitic acid group was detected by Western blotting. The mitochondrial AMPK competitive inhibitor peptide (mitoAIP) was overexpressed in AML12 cells, and the content of AMPK downstream proteins in the empty vector control group and the mitoAIP overexpression group were detected by Western blotting. mitoAIP was overexpressed in AML12 cells and treated with 2 mmol·L^-1 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR). The content of AMPK downstream proteins in the empty vector control group, the AICAR+empty vector control group, and the AICAR+mitoAIP overexpression group was detected by Western blotting. mitoAIP was overexpressed in AML12 cells, and the mitochondrial membrane potential was measured in the empty vector control group and the mitoAIP overexpression group using flow cytometry. mitoAIP and MitoTimer were overexpressed in AML12 cells, and the oxidative stress level of mitochondria in the pMitoTimer+empty vector control group and the pMitoTimer+mitoAIP overexpression group was measured using flow cytometry. mitoAIP was overexpressed in AML12 cells treated by oleic acid, and the fat deposition in the oleic acid+empty vector control group and the oleic acid+mitoAIP overexpression group was analyzed using Oil Red O staining. All cell experiments were repeated at least 3 times. The study found that AMPKα1 was the predominant isoform in goose hepatocytes, primarily localized in the mitochondrial fraction and specifically on the outer mitochondrial membrane. Both total AMPKα1 (tAMPKα1) and phosphorylated AMPKα1 (pAMPKα1) protein levels in whole-cell and mitochondrial lysates were lower in fatty liver compared to normal liver (P < 0.05, P < 0.01), the reduction in mitochondrial tAMPKα1 did not reach statistical significance. High glucose treatment did not significantly affect tAMPKα1 and pAMPKα1 protein abundance, while palmitic acid treatment reduced pAMPKα1 protein abundance in the mitochondrial fraction (P=0.079). In AML12 cells, overexpression of mitoAIP significantly increased the protein abundance of pAMPKα1, tAMPKα1, pACC1, and tACC1 in mitochondria (P < 0.05, P < 0.01), but had no significant effect on the protein abundance of AMPK and ACC1 in whole-cell lysate. AICAR treatment significantly increased the abundance of pAMPKα1 and pACC1 proteins in whole cell lysates (P < 0.05), but significantly reduced the abundance of pAMPKα1, tAMPKα1, pACC1, tACC1, and tULK1 proteins in the mitochondrial fraction (P < 0.05). Overexpression of mitoAIP significantly inhibited the AICAR-induced reduction in pACC1 abundance in whole cells (P < 0.05), but did not significantly affect the abundance changes of other proteins induced by AICAR treatment. mitoAIP overexpression caused a decrease in mitochondrial membrane potential, an increase in mitochondrial oxidative stress levels, and an increase in cellular fat content (P < 0.05, P < 0.01). In summary, mitoAIP differs from the known global AIP in regulating the abundance of AMPK and its substrate proteins in whole cells and mitochondria, as well as mitochondrial membrane potential and oxidative stress levels, suggesting that mAMPK plays a unique role in regulating mitochondrial function. The results of mitoAIP overexpression in AML12 cells suggest that the reducion of the phosphorylated mAMPK content in goose fatty liver may induce increase of fat deposition, decrease of mitochondrial membrane potential, and increase of oxidative stress level. However, these effects may also be regulated by other mechanisms.

This study aimed to investigate hypoxia adaptation mechanisms in plateau-dwelling mammals through transcriptomic comparisons of yak, dzho, and cattle, and identify genetic signatures associated with high-altitude hypoxic tolerance. Lung tissues were collected from healthy 3-4-year-old male yaks, dzhos (3 700 m altitude) of 330 kg, and cattle (500 m altitude) of 350 kg. All animals were grazed, with 3 replicates per species. RNA extraction and transcriptome sequencing were performed on the collected samples, followed by transcriptome difference comparison, GO and KEGG analysis and expression trend analysis among varieties. A total of 372.98 G of clean data were obtained. Differential expression analysis identified 2 318 DEGs between yaks and cattle, 1 487 DEGs between dzhos and cattle, and 1 064 DEGs shared by yaks and dzhos compared to cattle. These DEGs were enriched in biological processes like immune response, ion transport, and neuropeptide signaling, and pathways such as neuroactive ligand-receptor interaction and cAMP signaling, etc. Expression trend analysis showed 275 genes in 1 064 DEGs with clear increasing or decreasing patterns across yaks, dzhos, and cattle, involving membrane, cytoplasmic, and nuclear functions, as well as nervous system and immune-related pathways. Hypoxia adaptation genes, including IL1B, CHRNA7, ALAS2, HIF3A, and CAMK2A, were also identified, linking hypoxia response to immunity, neural processes, and erythropoiesis. This study revealed key gene expression differences among yaks, dzhos, and cattle, highlighting pathways related to immunity, hypoxia adaptation, and neural signaling, and elucidated its unique physiological characteristics and environmental adaptability. These findings provide molecular insights into hybrid advantages and high-altitude adaptation, supporting genetic improvement and disease control in plateau animals.

The aim of this experiment was to investigate the effect of adding luteolin (LUT) to the diluent on the cryopreservation effect of semen from Qinchuan cattle. In this study, fresh semen was collected from 6 Qinchuan breeding bulls aged 3-5 years, weighing (586±20) kg and in good health. The tested semen was mixed, diluted with freeze-diluent with different concentrations of LUT added, and frozen for preservation. According to the different concentrations of LUT added in the cryodilution solution, this experiment was divided into 5 groups: 0 mg·mL^-1 LUT group (control group), 0.02 mg·mL^-1 LUT group, 0.04 mg·mL^-1 LUT group, 0.08 mg·mL^-1 LUT group and 0.1 mg·mL^-1 LUT group, with 3 replicates set in each group. After thawing, sperm motility was measured using a bovine automatic sperm quality analyser; plasma membrane integrity was detected using the sperm hypotonic swelling test; sperm acrosome integrity and mitochondrial viability were detected using fluorescent staining; and spermatozoa were tested for catalase (CAT) activity, glutathione peroxidase (GSH-Px) activity, and malondialdehyde (MDA) content using a kit. Compared with the control group, sperm viability, linear motility speed, plasma membrane integrity and acrosome integrity were significantly increased in the 0.02 mg·mL^-1 LUT and 0.04 mg·mL^-1 LUT groups (P < 0.05). Meanwhile, sperm mitochondrial viability, CAT and GSH-Px activity in the 0.02 mg·mL^-1 LUT group, 0.04 mg·mL^-1 LUT group and 0.08 mg·mL^-1 LUT group were significantly increased (P < 0.05), and MDA content was significantly decreased (P < 0.05) in all experimental groups. The optimum amount of LUT added was 0.02 mg·mL^-1. The addition of LUT to the diluent could significantly improve the antioxidant capacity of spermatozoa in bovine semen, protect the structural integrity of spermatozoa, alleviate the damage to spermatozoa caused by the freezing-thawing process, and then enhance the motility of spermatozoa after thawing, thus effectively improving the quality of the frozen semen.

This study aimed to reveal the changes in plasma metabolism of non-pregnant Holstein dairy cows from the day of artificial insemination to day 28 and to screen biomarkers indicating non-pregnant dairy cows, to provide new ideas for reducing the idle time of dairy cows, shortening the calving interval and early pregnancy diagnosis. This study was conducted using healthy Holstein dairy cows (body weight: 550±50 kg, age: 3-4 years, parity: 2-3) from a dairy farm in Ningxia. Following estrus synchronization, artificial insemination (AI) was performed (designated as Day 0). Blood samples were collected from the tail vein (before morning feeding) at 4 time points: Day 0 (Group A), Day 5 (Group B), Day 17 (Group C), and Day 28 (Group D). Plasma was separated and stored at －80℃. On Day 32 post-AI, ultrasound examination confirmed 12 non-pregnant cows without return to estrus. Plasma samples from these cows (n=12) were analyzed using ultra performance liquid chromatography quadrupole time of flight mass spectrometry (UHPLC-QTOF-MS)-based untargeted metabolomics. The results showed as follows: 1) The plasma metabolism characteristics of non-pregnant cows were different at different periods after artificial insemination; 2) Among the 32 differential metabolites screened, 8 had higher sensitivity (AUC> 0.7). Compared with the day of artificial insemination, DL-vanillyl mandelic acid and lumichrome were highly expressed on the 5th day of insemination, and Trp-Glu, Ile-Arg, glycodeoxycholic acid, and 2-ethoxyethanol were highly expressed on the 17th day of insemination. However, Arg-Tyr and pristanic acid were highly expressed on the 28th day of insemination, and the plasma differential metabolites between d 0 and d 17 after insemination were mainly concentrated in the arginine biosynthesis pathway. The results indicate that arginine biosynthesis may be a key pathway affecting the occurrence of pregnancy in dairy cows. The 8 key metabolites with high AUC values such as DL-vanillyl mandelic acid and lumichrome may be biomarkers indicating that dairy cows are not pregnant early after artificial insemination. The results can provide new ideas for improving the reproductive efficiency of dairy cows.

This study aimed to investigate the effects of glycine, a small-molecule permeant that optimizes cellular volume regulation, on improving the cryopreservation efficiency of mink germinal vesicle (GV) stage oocytes during vitrification, thawing, and subsequent in vitro maturation (IVM). Ovaries were collected from sexually mature female minks (1-3 years old) during the breeding season (February-March).The collected oocytes were randomly divided into 3 groups: control (fresh oocytes), vitrified without glycine (vitrified group), and vitrified with 5 mmol·L^-1 glycine (vitrified+Gly group), each group contained at least 20 oocytes, each experiment was repeated at least 3 times. Glycine of 5 mmol·L^-1 was supplemented during vitrification, thawing, and IVM. Post-thaw assessments included survival rate, nuclear maturation rate, mitochondrial integrity, cortical granule distribution, reactive oxygen species (ROS) levels, apoptosis, and histone modifications (H3K9 methylation). Quantitative PCR and immunofluorescence were employed to analyze apoptosis-related genes (CASP3, BAX, BCL-2) and DNA methyltransferase 1 (DNMT1) expression. Glycine supplementation during vitrification and IVM significantly enhanced the biological function of cryopreserved oocytes. Compared to the non-glycine vitrified group, glycine-treated oocytes exhibited higher survival rate (P < 0.05) and nuclear maturation rates (P < 0.05). Mitochondrial damage and cortical granule mislocalization were reduced (P < 0.05), while ROS levels decreased (P < 0.05). Apoptosis rates declined with downregulated CASP3 and BAX expression (P < 0.05) and an elevated BCL-2/BAX ratio (P < 0.05). Additionally, glycine improved DNMT1 transcription (P < 0.05) and H3K9 methylation levels (P < 0.05) in MII oocytes post-vitrification. In summary, oocytes osmosis damage caused by addition or removal of cryoprotectants during vitrification can regulate oocyte volume homeostasis by addition of glycine, thereby improving the developmental ability of vitrification mink oocytes.

The purpose of this experiment was to use resiquimod (R848) and polyvinylpyrrolidone (PVP) to prepare the sorting solution for sorting sika deer sperm, and to establish a time-saving, simple, and efficient method for separating sika deer Y sperm, to improve the reproductive efficiency and increase the number of male offspring in production. In this study, semen was collected from 3 healthy adult male sika deer, and a sperm viability analyzer and confocal microscope were used to assess the effects of 5 different basal fluids, R848 concentrations, PVP concentrations, and incubation times on sperm counts, motility parameters (viability, progressive motility, average path velocity, curvilinear velocity, straight-line velocity, and straightness), and sperm quality (plasma membrane and acrosome integrity). The DNA karyotype of the sorted upper monosperm was detected using the monosperm karyotyping technique to determine the effect of Y-sperm sorting, and the sorted semen was evaluated for fertilizing ability by in vitro fertilization. The results showed that among the 5 basal fluids, sperm motility was significantly higher in formulation 1 and 2 than that in formulation 3, 4, and 5, and there was no significant difference between formulation 1 and 2; the upper sperm counts were significantly lower in all treatment groups as the concentrations of R848 and PVP increased, and the upper sperm counts in both the R848 group (group R) and the R848+PVP group (group R+P) were significantly lower than those in the control group (group C) at 60 and 90 min. The motility parameters and sperm quality in group R and R+P showed significantly lower average path velocity and curvilinear velocity, significantly higher straightness, and no significant changes in viability, progressive motility, straight-line velocity, plasma membrane and acrosomal integrity, compared to group C. The upper Y spermatozoa detection rate was 80% in group R and 90% in group R+P, which were significantly higher than that in group C (50%), and the spermatozoa cleavage rate of group R+P was not significantly higher than that in group C. In this experiment, the method of R848+PVP combined incubation was used, and the upper Y sperm separation rate was up to 90%. A kind of deer Y sperm separation technology without CO₂ incubator and semen freezing was preliminarily established, which provided technical support for the separation and production of sexed semen of sika deer.

This experiment was conducted to evaluate the effects of golden buckwheat stem and leaf meal (GBSLM) supplementation in Gannan Tibetan primiparous sows diet by determining nutrient apparent digestibility, serum biochemical indices and fecal microflora composition. Eighteen healthy pregnant primiparous Gannan Tibetan sows with similar body condition and expected delivery date were randomly allocated to 3 groups with 6 replicates in per group and 1 pig in per replicate. Pigs in the control group (CON group) were fed only the basal diet, while the other groups (T1 and T2 groups) were fed the basal diets supplemented with 10% and 20% GBSLM, respectively. The trial period was from day 70 of gestation to 28 day after delivery. The results showed that: 1) Compared with the CON group, the apparent digestibility of gross energy (GE) and dry matter (DM) of sows at 105 day of gestation in T1 and T2 groups were significantly increased (P < 0.05), ether extract (EE) and phorsphorous in T1 group increased significantly (P < 0.05), while the apparent digestibility of crude protein (CP) in T2 group was pronouncedly decreased (P < 0.05). At 15 day after delivery, sows in T2 group had significantly higher apparent digestibility of GE, DM, EE and Ash than those of the CON group (P < 0.05). 2) In comparison to the CON group, the T1 and T2 groups dramatically heighted the TP content (P < 0.05) and lowered the GLU content (P < 0.05) in serum of sows after day 105 of gestation. 3) Firmicutes, Bacteroidota and Spirochaetota were the dominant bacteria phyla shared by the three groups. On the 105th day of pregnancy, the relative abundance of Bacteroidota in feces of sows in T1 and T2 groups were markedly higher than that in CON group (P < 0.05). Although the relative abundance of Firmicutes were lower in the T1 and T2 groups compared to the CON group, no significant effects were observed (P>0.05). Furthermore, contrasted with the CON group, the T2 group statistically diminished the relative abundance of Actinobacteria in feces of sows at day 15 after parturition (P < 0.05). Streptococcus, Clostridium_sensu_stricto_1 and Terrisporobacter were the dominant genera shared by the three groups. Moreover, on the 105th day of pregnancy, the T1 and T2 groups had an apparently higher fecal UCG-005, Rikenellaceae_RC9_ gut_group and Prevotellaceae_NK3B31_group relative abundance (P < 0.05) and an obviously lower fecal Streptococcus relative abundance compared to the CON group (P < 0.05). In conclusion, diets supplemented with GBSLM are conducive to elevating the apparent nutrients digestibility of GE, DM, EE, P and Ash, increasing the serum level of TP, regulating the richness and diversity of intestinal flora in Gannan Tibetan sows. Under the conditions of this experiment, GBSLM can be used in the diet of Gannan Tibetan sows and the addition of 10% GBSLM is the optimal dose.

The aim of this study was to explore whether phosphatidylethanolamine (PE) could improve the colonic mucosal barrier function and alleviate gut microbiota disorder of postnatal growth retardation (PGR) piglets. At the age of 7 days, 16 PGR piglets (average body weight 1.88±0.40 kg) and 16 normal body weight(NBW) piglets (average body weight 2.79±0.50 kg) were randomly divided into 4 groups: CON-NBW (CN) group, PE-NBW (PN) group, CON-PGR (CP) group and PE-PGR (PP) group, with 8 replicates in each group and 1 piglet in each replicate. The piglets in PN and PP groups were fed with 0.78 g PE per day during lactation and 2.11 g PE per day after weaning. The piglets in CN and CP groups were fed with equal volume of 0.9% saline. All piglets were weaned at 28 days of age and the experiment lasted for 42 days. The piglets were slaughtered at 49 days of age, and the colonic tissues and contents of piglets were collected for the determination of colonic mucosal barrier function related indicators and 16S rDNA sequencing of colonic contents. The results showed that compared with NBW piglets, the colon morphology of PGR piglets was damaged, and the number of goblet cells, the mRNA expression of ZO-1, spdef and MUC2 were significantly decreased (P < 0.05). At the same time, the piglet status (NBW or PGR) and PE treatment had a significant impact on the β diversity of colonic microbiota in piglets (P < 0.05). The ratio of Firmicutes and Bacteroides, the relative abundance of Actinobacteria, Macrosphaera and Gemmiger in the colon of PGR piglets were significantly lower than that of NBW piglets, while the relative abundance of Proteobacteria was significantly higher than that of NBW piglets (P < 0.05). PE supplementation alleviated the colonic morphological damage of PGR piglets, promoted the differentiation of colonic goblet cells and the secretion of MUC2, and increased the relative abundance of butyric acid producing bacteria in the colon (P < 0.05). Therefore, PE improved the mucus synthesis and secretion function and alleviated gut microbiota disorder of PGR piglets.

The aim was to investigate the effects of different mixing ratios of silage dietary on the volatile flavor compounds of lamb meat. Eighteen 3-month-old male Australian White×Hu sheep hybrid F1 lamb, with similar body weights and genetic backgrounds, were randomly divided into 3 groups (n=6): T1, T2, and T3, and were fed mixed silages of whole-plant corn and whole-plant soybean at ratios of 8 ∶2, 7 ∶3, and 6 ∶4, respectively. After 60 days of feeding, longissimus dorsi muscle samples were collected to analyze fatty acid profiles and volatile compounds (VOCs) using headspace gas chromatography-mass spectrometry (HS-GC-MS). Key flavor compounds in the lamb meat were identified through variable importance in the projection (VIP), odor activity value (OAV), and volatile compound annotation methods. Results showed that monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) in the T3 group were significantly higher than those in the T2 group (P < 0.05). A total of 290 VOCs were identified in lamb meat, and categorized into 14 classes, with aldehydes, alcohols, ketones, and esters being the most abundant. OAV analysis identified 12 VOCs contributing to lamb flavor, among which aldehydes exhibited the highest overall contribution. The OAVs of decanal, nonanal, octanal, and heptanal in the T3 group were significantly higher than those in the T1 group (P < 0.05). VIP and OAV analyses with flavor annotations revealed that octanal, decanal, and 1-octen-3-ol served as both differential volatile markers among treatments and key contributors to desirable lamb flavors, including grassy, sweet, fruity, and floral. In summary, octanal, decanal, and 1-octen-3-ol are critical VOCs driving flavor differences in lamb meat under varying silage ratios, with the 6∶4 corn-to-soybean (T3) blend optimal for enhancing flavor quality. This research elucidates the impact of mixed corn-soybean silage diets on lamb flavor and provides a scientific basis for optimizing dietary formulations to improve meat flavor.

This experiment was conducted to investigate the effects of dietary folic acid levels on production performance, plasma biochemical indicators, and antioxidant capacity of Pekin ducks from 1 to 21 days of age, and to determine the folic acid requirement of Pekin ducks. The experiment adopts a completely randomized single-factor experimental design. A total of 640 1-day-old male Pekin ducks with similar body weight were randomly divided into 8 groups, 8 replicates per group, and 10 ducks per replicate. Ducks were fed experimental diets with folate levels of 0.16, 0.26, 0.36, 0.56, 0.76, 0.96, and 1.16 mg ·kg^－1, respectively. The experiment lasted for 21 days. The results showed as follows: 1) Average body weight and average daily weight gain in the 0.76 mg ·kg^－1 folic acid group were significantly higher than that in the 0.26, 0.36, and 0.56 mg ·kg^－1 folic acid groups (P < 0.05). 2) With dietary folic acid level increasing, breast muscle percentage (P=0.098 8) and leg muscle percentage (P=0.075 3) has the trend of first increasing and then decreasing. 3) With dietary folic acid level increasing, plasma aspartate aminotransferase activities were significantly decreased, and plasma glucose level was significantly increased (P < 0.05). When folic acid level was 0.76 mg ·kg^－1, there was no significant change in the above indexes. 4) The total antioxidant capacity of 0.16 and 0.36 mg ·kg^－1 folic acid groups was significantly lower than that of 0.26 and 0.76 mg ·kg^－1 folic acid groups (P < 0.05). The catalase activity of 0.16 and 0.26 mg ·kg^－1 folic acid groups was significantly lower than that of 0.36, 0.56, 0.76, 0.96, and 1.16 mg ·kg^－1 folic acid groups (P < 0.05). In conclusion, adding an appropriate level of folic acid to the diet could improve the production performance and antioxidant capacity of Pekin ducks. The recommended folic acid level in the diet for Pekin duck from 1 to 21 days of age under the condition of the current study is 0.76 mg ·kg^－1.

The purpose of this study was to investigate the effects of lactic acid bacteria (LAB) on the growth performance, digestive function, and nutrient utilization of yellow-feathered chickens. A total of 480 male yellow-feathered broiler chickens with an initial body weight of (31.95±0.56)g were randomly divided into 3 groups, with 8 replicates per group and 20 chickens per replicate. The experiment lasted for 70 days, which was divided into an early phase (1-35 days) and a late phase (36-70 days). The broiler chickens in the control group (CON) were fed a basal diet, while the experimental groups (LAB1 and LAB2) were fed diets supplemented with 500 mg ·kg^－1 or 1 000 mg ·kg^－1 of LAB (with a live bacteria count of 1×10⁸ CFU ·g^－1), respectively. The results showed that broiler chickens in the LAB1 and LAB2 groups had higher gizzard and pancreas indices at 35 days of age, higher pancreas indices at 70 days of age, higher apparent metabolic rates of organic matter at 33-35 and 68-77 days of age and crude protein at 68-70 days of age, and lower serum urea nitrogen content at 35 days of age compared to those in CON group (P < 0.05). The broiler chickens in the LAB2 group exhibited significantly higher final body weight, average daily weight gain, average daily feed intake, and apparent metabolic rate of crude protein at 68-70 days of age than those of both the CON and LAB1 groups (P < 0.05).The LAB1 and LAB2 groups showed higher lipase activity in the pancreas at 35 days of age, higher amylase and lipase activities in the jejunal chyme at 35 days of age, higher trypsin, amylase, and lipase activities in the jejunal chyme at 70 days of age, and higher expression of Trypsin genes at 35 and 70 days as well as Amylase genes at 70 days in the pancreas compared to the CON group. The LAB1 group had higher trypsin activity in the jejunal chyme at 35 days of age than the CON and LAB2 groups, and the LAB2 group had higher trypsin activity at 70 days of age in the pancreas and higher amylase and trypsin activities in the jejunal chyme at 70 days of age compared to the CON and LAB1 groups (P < 0.05). In conclusion, dietary supplementation with LAB upregulated the expression of digestive enzyme genes, increased the activity of digestive enzymes in the pancreas and jejunal chyme, reduced serum urea nitrogen content, improved the apparent metabolic rates of organic matter and crude protein, enhanced digestive organ development, and improved the growth performance in broiler chickens. The effects were more pronounced with the 1 000 mg ·kg^－1 LAB supplementation under the condition of the current experiment.

The purpose of this study was to investigate the effects of dietary supplementation with Bacillus licheniformis on the immune response function, antioxidant capacity, cecal short-chain fatty acid content and microflora of E22-challenged broilers. In this experiment, 360 1-day-old male yellow-feathered broilers were randomly divided into 4 groups, with 6 replicates in each group, and 15 broilers in each replicate, and the experimental period was 28 days. The control group (CON) was fed basal diet+perfusion with blank LB medium. In the BL group, broilers were fed basal diet+Bacillus licheniformis; E22 group, they were fed basal diet+E. coli E22 bacterial solution; BL+E22 group was fed with basal diet+Bacillus licheniformis+E. coli E22 solution. The results showed that: 1)compared with the control group, the addition of Bacillus licheniformis (BL group) to the feed significantly increased the organ index of broiler liver, the levels of IgG, IgY, IgM and anti-inflammatory factor IL-10 in serum (P < 0.05), and significantly reduced the level of pro-inflammatory factor TNF-α in broiler serum (P < 0.05); Meanwhile, compared with the E22 group, the BL+E22 group significantly increased the organ index of broiler thymus, IgG, IgY, and IgM levels, and significantly reduced the levels of inflammatory factors IL-1β and TNF-α (P < 0.05). 2) Compared with the control group, the BL group significantly increased the activities of serum SOD and GSH-PX in broiler chickens (P < 0.05), and significantly reduced the content of MDA (P < 0.05). Compared with the E22 group, the BL+E22 group significantly increased the activity of GSH-Px in broiler serum and significantly decreased the activity of MDA in broiler serum (P < 0.05). 3) Compared with the control group, the BL group significantly increased the content of acetic acid in the cecal contents of broiler chickens (P < 0.05), and significantly decreased the content of isobutyric acid and isovaleric acid (P < 0.05). Compared with the E22 group, the BL+E22 group significantly increased the content of acetic acid and propionic acid (P < 0.05). 4) 16S rRNA gene sequencing showed that the BL group significantly increased the relative abundance of Barnesiella_viscericola and unclassifiedd_g__Barnesiella (P<0.05). In conclusion, the addition of Bacillus licheniformis to the diet could improve the immunity, antioxidant capacity and cecal SCFAs content of broilers, and improve the diversity of cecal microbial populations. At the same time, Bacillus licheniformis in the diet can alleviate the inflammation, oxidative stress response and intestinal flora disorder caused by E. coli infection to a certain extent.

The aim of this study was to investigate the protective effect and mechanism of selenium (Se) polysaccharide (Sepol) preprotection on H₂O₂-induced oxidative stress in Mongolian horse skeletal muscle satellite cells, and to provide a reference for the development of antioxidants to alleviate exercise injury in horse skeletal muscle.The oxidative injury model of Mongolian horse skeletal muscle satellite cells was induced by H₂O₂ and used to perform the experiment. The experiment was divided into control group, H₂O₂ injury group and selenium polysaccharide protection groups (concentrations of selenium polysaccharide protection group were 50, 150, 250, 350, 450, 550 nmol ·L^-1, respectively). Cell viability, antioxidant activity, antioxidant gene expression and mitochondrial function were measured.The results showed that: Cell viability, total antioxidant capacity (T-AOC), activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX) increased first and then decreased with the increase of pre-protective concentration of seleniumpolysaccharide. The cell survival rate of 350 nmol ·L^-1 Se polysaccharide preprotection group was significantly higher than that of injury group (P < 0.05) and there was no significant difference between 350 nmol ·L^-1 Se polysaccharide preprotection group and control group, but the activity of antioxidant enzymes was significantly higher than that of injury group and control group (P < 0.05). The content of malondialdehyde (MDA) in cells decreased first and then increased with the increase of Se polysaccharide. The content of MDA in 350 nmol ·L^-1 Se polysaccharide preprotection group was the lowest, which was significantly lower than that in control group and injury group (P < 0.05).The mRNA expression of proto-oncogene RELA(RELA proto-oncogene, RELA), glutathione peroxidase (probable phospholipid hydroperoxide glutathione peroxidase, GPX), thioredoxin reductase 1 (TRXR 1 ) and superoxide dismutase 1 (SOD 1 ) in the 350 nmol ·L^-1 selenium polysaccharide pre-protected group was highly significant higher than that of the injured group (P < 0.01). The mRNA expression of RELA was significantly higher than that of the control group (P < 0.05), the mRNA expression of GPX, TRXR1 and SOD1 was extremely significantly higher than those of the control group (P < 0.01). mRNA expression of the nuclear factor-like erythroid 2-related factor 2 (Nrf2 ) in the 350 nmol ·L^-1 selenium polysaccharide preprotected group was significantly higher than that of the other two selenium polysaccharide preprotected groups (P < 0.05).The oxygen consumption rate (OCR) of 350 nmol ·L^-1selenosaccharide group was significantly higher than that of H₂O₂injury group (P < 0.05).The basal respiration, ATP consumption, proton leak and maximal respiration were 34.86, 26.06, 8.80 and 32.41, respectively, which were significantly higher than those of H₂O₂ injury group (P < 0.01). The non-mitochondrial respiration value was significantly higher than that of the injury group (P < 0.05).In conclusion, selenium polysaccharide can alleviate oxidative damage of horse skeletal muscle satellite cells by activating Nrf2 signaling pathway and up-regulating the expression of downstream antioxidant genes, thereby improving antioxidant enzyme activity, reducing MDA content, promoting mitochondrial respiratory function, and improving cell activity. Under the current experimental conditions, 350 nmol ·L^-1 selenium polysaccharide had the best effect.

This study aimed to establish a rapid, simple, specific and sensitive colloidal gold-based universal detection method for antibodies against Capripoxvirus. By constructing a recombinant vector and expressing and purifying the recombinant 122 protein of the Capripoxvirus in a prokaryotic system, rabbit polyclonal antibodies were prepared. The 122 protein was conjugated with colloidal gold as the gold-labeled antigen. Then, the 122 protein and rabbit polyclonal antibodies were coated onto a nitrocellulose membrane (NC) as the test line (T line) and control line (C line), respectively. After optimizing the conditions, a colloidal gold immunochromatographic test strip for detecting Capripoxvirus antibodies was developed. The results showed that the prokaryotically expressed recombinant 122 protein was approximately 32 ku in size. The developed colloidal gold test strip could specifically detect Capripoxvirus antibodies within 12 minutes; there was no cross-reaction with positive sera of other common livestock diseases. The sensitivity for detecting sheeppox virus lumpy skin disease virus and goat-pox virus positive sera was 1 ∶64, 1 ∶128, and 1 ∶128, respectively, which was comparable to the sensitivity of the commercially available indirect ELISA diagnostic kit for Capripoxvirus antibodies (titers 1 ∶128, 1 ∶256, 1 ∶256). The detection of 130 clinical serum samples was compared with the results of the commercial kit, and the kappa value was 0.93, indicating a high degree of consistency. This study successfully developed a universal colloidal gold immunochromatographic test strip for detecting Capripoxvirus antibodies, which has high sensitivity and specificity, as well as low cost, rapid detection, simple operation, and easy interpretation of results, providing practical application value for on-site detection of Capripoxvirus.

This study aims to extract Brucella melitensis biotype 3 outer membrane vesicles (OMVs), analyze their protein components, and prepare an OMV subunit vaccine to evaluate its immunogenicity. OMVs were extracted using differential centrifugation, and characterized by SDS-PAGE, transmission electron microscopy, and ZeTA nanoparticle size analysis. The protein components of the OMVs were identified using label-free liquid chromatography-mass spectrometry (LC-MS), followed by Gene Ontology (GO) clustering and KEGG pathway enrichment analysis. After immunizing mice with the OMV subunit vaccine, histopathological analysis of mouse spleens and T cell subpopulation classification were performed. Inflammatory cytokine levels, including IL-2, IFN-γ, TNF-α, IL-4, IL-6, IL-10, and IL-17A, as well as immunoglobulin levels (IgG1, IgG2a, and IgG2b) in mouse serum samples, were measured to assess the pathological changes and cellular immune response post-immunization. Results were as follows: OMVs were successfully extracted with particle sizes ranging from 20 to 200 nm and molecular weights between 10 to 130 ku. Proteomic analysis identified 1 612 proteins in OMVs, including several outer membrane proteins such as Omp2b, Omp25, Omp31, Omp19, and Bp26, as well as lipoproteins and proteins related to ABC transporters. After immunization with the OMV subunit vaccine, no significant lymphocyte disorganization or necrosis was observed in mouse spleens. The vaccine induced high levels of IgG immunoglobulin and elevated the expression of inflammatory cytokines IFN-γ, IL-2, IL-6, IL-17A, and TNF-α, while reducing IL-10 and IL-4 levels. The CD4⁺/CD8⁺T cell ratio also increased. The study demonstrates that OMVs contain several effective immunogenic antigens capable of inducing strong cellular immune responses in mice. This lays the theoretical foundation for identifying the protein components of OMVs and developing Brucella subunit vaccines.

Escherichia coli is one of the main pathogens causing diarrhea and death in newborn calves. The pathogenicity, virulence gene carriage, and antibiotic resistance prevalence of Escherichia coli causing diarrhea in calves in Heilongjiang Province were investigated. Two hundred and fifty-two diarrhea samples of calf were collected from 35 herds in 8 cities from January 2020 to July 2023. Bacterial isolation, Gram staining, identification on differential media, biochemical tests, 16S rRNA identification, mouse pathogenicity tests, and drug sensitivity tests were conducted. The presence of 15 virulence genes was detected using PCR. Experimental data were analyzed using the chi-square test method of SPSS 22.0 software to assess the regional prevalence of pathogenic E. coli, as well as factors related to different years and seasons. Results showed that a total of 153 strains of pathogenic E. coli were isolated and identified, of which 49.02% (75/153) carried virulence genes. The highest positive rate was for Irp-2 at 37.25% (57/153), followed by FyuA, K99、F41, F17, STa, HlyA, Stx1, Stx2 and EaeA at 19.61% (30/153), 4.58% (7/153), 4.58% (7/153), 3.92% (6/153), 2.61% (4/153), 3.27% (5/153), 0.65% (1/153), 0.65% (1/153), and 0.65% (1/153), respectively. Drug sensitivity tests indicated that the highest sensitivity rate of the 153 isolated strains was to fosfomycin at 56.21% (86/153), while there was severe resistance to sulfisoxazole, amoxicillin, etc. All strains were resistant to two or more drugs, with some reaching resistance to as many as 11 drugs. Statistical analysis revealed that the isolation rate of pathogenic E. coli in 2020 was significantly higher at 77.59% (45/58) compared to 2021 and 2022 (P < 0.001). Among the four seasons, the summer had the lowest isolation rate of pathogenic E. coli (P < 0.05). And the rate of pathogenic E. coli was statistically different among regions, with the highest in Jixi and the lowest in Qiqihar (P < 0.001). These results indicate that the pathogenic E. coli strains causing calf diarrhea in the Heilongjiang region carry a diverse range of virulence genes and are generally resistant to multiple drugs. The prevalence of pathogenic E. coli is correlated with region, year, and season. This study provides a theoretical basis for the prevention and control of E. coli infections in cattle in the Heilongjiang region.

This study aimed to explore the biological characteristics, drug sensitivity and pathogenicity of Lactococcus garvieae from pig. Suspicious bacteria were isolated from the liver of diseased pig, and then were identified by Gram stained microscopy, matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), 16S rRNA gene sequence analysis and sequence analysis. The drug resistance and pathogenicity of isolated strains were explored through drug sensitivity testing and mice infection testing. Related virulence of isolated strain genes were amplified by PCR. Results were as follows: A positive strain of α-hemolytic was isolated from the liver of a diseased pig. MALDI-TOF MS, PCR amplification of 16S rRNA gene and phylogenetic tree analysis results showed that the isolated strain was identified as Lactococcus garvieae.The infection test of mice showed that the isolated strain had strong lethality. It can cause swelling of the liver and spleen, severe congestion of the intestines, abdominal cavity, and chest cavity in mice. The drug sensitivity test results showed that the isolated strains were resistant to β-lactam drugs such as penicillin G and ampicillin, as well as erythromycin and lincomycin, and sensitive to other antibiotics. The results of virulence gene testing showed that the isolated strain contains adhesion related genes adhC1, psaA, eno, lp1, hemolysis related genes hly1, hly2, hly3, capsule gene cluster formation related genes cgcC, polysaccharide related genes epsA, epsB, epsC, epsD, epsL, and other virulence genes nadho, sod, pgm, chp. The Lactococcus garvieae was isolated in this experiment has strong pathogenicity, and its potential risks cannot be ignored as it belongs to zoonotic pathogens. This study provides data reference for the prevention and treatment of clinical infections caused by Lactococcus garvieae.

To explore whether the TR and ROP5 of Toxoplasma gondii have a synergistic effect on anti-host ROS damage, we used CRISPR/Cas9 technology in this study to successfully obtain the TR and ROP5 double gene knockout strain (TR-ROP5-KO). By biological activity analysis, we discovered that the invasion, proliferation ability in vitro, and virulence in vivo of TR-ROP5-KO strain were lower than those of RH strain, TR gene deletion strain (TR-KO) and ROP5 gene deletion strain (ROP5-KO). These results indicated that the simultaneous deletion of TR and ROP5 in Toxoplasma gondii not only lead to a decrease in the viability of the parasites in vitro cells, but also reduce the virulence of toxoplasma in the host. The results of the oxidative stress levels of T. gondii and their effects on ROS levels in mouse macrophages cells showed that the level of oxidative stress induced by TR-ROP5-KO strain was significantly higher than by RH strain (P < 0.05), but there was no differences relative to TR single gene deletion strain (P > 0.05). The mRNA levels of NF-κB, IL-12 and IFN-γ in mouse macrophages infected with TR/ROP5 single and double gene deletion strains were detected by RT-qPCR, and the levels of IL-12 in serum of mice was also detected by ELISA. The results suggested that the TR-ROP5-KO infection group was significantly higher than RH group (P < 0.05), but the TR-ROP5-KO infection group was not significantly higher than the TR-KO infection group (P > 0.05). The results indicated that TR and ROP5 genes have no synergistic effect on resisting the ROS damage of host. In this study, the method of constructing double-gene deletion strains of TR and ROP5 showed that the two genes had no synergistic effect on the anti-ROS damage of the host, which provided the method basis for the subsequent research on the function of multiple genes of Toxoplasma gondii and the basic material for the research on the immune escape mechanism of Toxoplasma gondii.

This study aims to explore the impact of CCAAT/enhancer-binding protein beta (CEBPB) on porcine deltacoronavirus (PDCoV) replication. PDCoV was inoculated in LLC-PK1 cells, and the expression levels of CEBPB at different time points were detected. Overexpression and knockdown of CEBPB were performed, and their effects on PDCoV replication were assessed using qPCR and Western blot. Furthermore, the role of CEBPB in the PDCoV replication cycle was clarified. Viral proteins that influenced the upregulation of CEBPB were screened using qPCR, and the colocalization of PDCoV viral proteins with CEBPB was observed using confocal microscopy. The results showed that CEBPB expression increased with prolonged virus infection time. Overexpression of CEBPB significantly inhibited PDCoV replication, while knockdown of CEBPB promoted virus replication. CEBPB mainly acted during the replication stage of PDCoV, and PDCoV Nsp4 could promote CEBPB expression. Confocal microscopy revealed colocalization of Nsp4 and CEBPB. In conclusion, CEBPB could significantly inhibit PDCoV replication in vitro, which provided important data for the development of antiviral drugs based on CEBPB.

The aim of this study was to establish a rapid and effective method for detecting infections bursal disease virus (IBDV), monoclonal antibodies were prepared using the whole IBDV as the immunogen. Double antibody sandwich ELISA method was established using monoclonal antibody 6G3 as the capture antibody and monoclonal antibody 4C12 as the detection antibody for the detection of IBDV. The results showed that the ELISA method had good specificity and no cross-reaction with REV, AEV, ALV or EDSV. The sensitivity test showed that the minimum detectable amount of IBDV is 1.585×10³ELD₅₀. The results of inter and intra plate repeatability tests showed that this method had good repeatability. Forty-nine clinical samples were detected by the double antibody sandwich ELISA method and commercial IBDV antigen detection card, and the coincidence rate was 94.18%. In conclusion, the double-antibody sandwich ELISA method established in this study has good specificity, sensitivity and repeatability, and can be used for rapid detection of IBDV. Thus, laysing the foundation for the development of a commercial IBDV detection kit.

A monoclonal antibody (McAb) to porcine interleukin-15 (IL-15) was prepared and a quantitative IL-15-ELISA was established. Porcine IL-15 prokaryotic expression vector pET-28a-IL15 was constructed, and the recombinant protein was expressed with Escherichia coli (E. coli) prokaryotic expression system, and six-week-old female BALB/c mice were immunized with recombinant IL-15. On day 3 after the booster immunization, splenocytes were isolated and collected from one mouse to fuse with SP2/0 cells. Positive hybridoma cells were screened and monoclonal antibodies to IL-15 secreted by the positive hybridoma cells were identified. Moreover, a sandwich ELISA for detection of porcine IL-15 based on a monoclonal antibody. Nine strains of hybridoma cells (1E8, 1F4, 2D3, 2C10, 2F3, 2D10, 3F4, 3D4 and 3D5) secreting anti-IL-15 McAb were obtained, and all of the secreted McAb were of the IgG2bκ type. A sandwich ELISA using the prepared monoclonal antibody 2D10 as the capture antibody and 2C10 as the enzyme-labeled antibody, respectively, was able to detect a minimum of 31.25 ng·mL^-1 of IL-15 protein, with no cross-reactivity with the other cytokines or protein (IL-1, IL-2, IL-4, IL-6, IL-10, IL-12, Gzms-B, IFN-γ, and TNF-α). The mean coefficient of variation for intra-batch and inter-batch reproducibility experiments was 2.56% and 3.39%, respectively. This sandwich ELISA quantifies IL-15 in serum, tissue fluid and cell culture. Porcine IL-15 McAb was successfully prepared, and a double antibody sandwich ELISA method was established, which provided an important tool for IL-15 related studies.

Chitinase 3-like protein 1 (CHI3L1) expression levels significantly change after infection with influenza A virus (IAV), suggesting that it may play a role in regulating the antiviral immune response. However, no direct interaction between CHI3L1 and IAV has been found so far. Since CHI3L1 may play an important role in the immune process, researchers hypothesized that it may play a key role in regulating the antiviral immune response. However, the current research tools are insufficient. Therefore, there is an urgent need to develop an efficient method for detecting CHI3L1 to facilitate subsequent research. In this study, CHI3L1 was targeted as the protein of interest, and a eukaryotic expression plasmid was constructed for its successful in vitro expression and purification. The purified protein was immunized with alpacas. After four immunizations, peripheral blood was collected from the alpacas and lymphocytes were isolated, and the antibody level was determined to be 1:64 000, which met the standard for constructing phage display libraries. Then, a single heavy chain variable region (VHH) gene was amplified using nested PCR and cloned into the pComb phage vector, successfully constructing a library with a capacity of 1.2×10⁸ cfu·mL^-1 of CHI3L1 nanobody phage display library. Through three rounds of immune affinity selection and enrichment, four specific nanobodies (Nb) were selected. Subsequently, the CHI3L1-specific nanobody expression plasmid was further constructed and transfected into 293F cells for expression, and the protein was purified using the Protein A affinity purification system. The Nb-YC8 and Nb-YC4 showed good binding affinity as determined by ELISA. Western blot was used to further verify that these nanobodies were able to correctly recognize CHI3L1 protein compared to commercial antibodies. Immunofluorescence analysis showed that Nb-YC4, Nb-YD10 and Nb-YF8 could recognize CHI3L1 protein expressed in 293T cells, while Nb-YC8 failed to recognize CHI3L1, suggesting that it may recognize a linear epitope. In this study, four strains of CHI3L1-specific nanobodies with different affinities were successfully screened and identified, which are expected to be powerful tools to study the function of CHI3L1 in the body's immune system. Further studies of CHI3L1 may help to uncover its potential role in the antiviral immune response and provide a basis for the development of CHI3L1-based diagnostic or therapeutic approaches.

Angiotensin-converting enzyme 2 (ACE2) plays a role in the regulation of various tissues and organs in the body, and its role in maintaining intestinal homeosta has become widely accepted. However, its role in animal coronaviruses, especially in porcine epidemic diarrhea virus (PEDV) infection, is still unclear. By analyzing the relationship between ACE2 and the pathological changes in intestinal tissues of clinically infected piglets with PEDV, the correlation between ACE2 and PEDV infection was studied. With PED clinically infected piglets as research objects, duodenum, jejunum and ileum tissues were isolated and intercepted. PCR, histopathology, Western blot, RT-qPCR and Spearman correlation analysis were used to determine PEDV infection and its expression distribution in the small intestine, observe the pathological changes in the small intestine, and analyze the expression changes of ACE2, IFN-α and related factors in the small intestine. To investigate the role of ACE2 and PEDV infection. The results showed that PEDV infection was found in the small intestine of piglets and distributed in the jejunum and ileum. PEDV infection caused necrosis and shedding of small intestinal epithelial cells, atrophy and shortening of intestinal villi, etc. The contents of Ang Ⅱ and pro-inflammatory factors TNF-α, IL-6, IL-8 and IL-1β in the small intestine were significantly increased, while the contents of Ang (1-7) and anti-inflammatory factors TGF-β1 and IL-10 were significantly decreased. The expression of ACE2, MasR, and IFN-α protein, as well as the expression of ISG15, ISG54, and ISG56 mRNA mediated by IFN-α, were all significantly downregulated, while the expression of ACE and AT1R proteins was all significantly upregulated. PEDV infection was negatively correlated with the ACE2-Ang (1-7)-MasR axis and positively correlated with the ACE-Ang Ⅱ-AT1R axis, negatively correlated with IFN-α expression, while ACE2 was positively correlated with IFN-α expression. The results suggest that PEDV infection induces intestinal inflammatory lesions in piglets, with both the expression of IFN-α and the ISGs mediated by it being suppressed in the small intestine. All members of the renin-angiotensin system (RAS) are present locally in the intestine, and two of its pathways are involved in the inflammatory injury process of PEDV-induced intestinal lesions in piglets, characterized by the activation of the ACE-Ang Ⅱ-AT1R axis and the inhibition of the ACE2-Ang (1-7)-MasR axis. ACE2 is closely related to PEDV infection and its induced interferon response.

Staphylococcus aureus (S. aureus) triggers an inflammatory response in the host upon invading mammalian systems, but the role of its lipoproteins in cytokine release and PGE₂ synthesis remains unclear. This study used the S. aureus SA113 strain, its lipoprotein-deficient mutant, and the complemented strain to infect bovine bone marrow-derived macrophages (bBMMs), aiming to investigate the role of S. aureus lipoproteins in stimulating cytokine release and PGE₂ production in immune cells. In this study, the mechanism of action of S. aureus lipoprotein in inducing the secretion and synthesis of immune cell inflammatory mediators and PGE₂ by infecting bovine bone marrow-derived macrophages with SA113, S. aureus SA113 isogenic mutant lgt: : ermB (Δlgt) deficient in lipoprotein maturation, and its complemented strain SA113 lgt: : ermB +pRBlgt (+pRB). The results showed that compared to the SA113-infected group, the secretion level of PGE₂ significantly decreased after infecting bBMMs with the S. aureus Δlgt mutant, while the secretion levels of pro-inflammatory cytokines (TNF-α and IL-1β) and anti-inflammatory cytokine (IL-10) also significantly decreased. Western blot results indicated that S. aureus lipoprotein influenced the activation of the NF-κB/MAPK pathway in bBMMs and the expression of PGE₂ synthetic enzymes COX-2 and mPGES-1. In addition, the expression levels of TLR2, TLR4 and NLRP3 genes in bBMMs were significantly reduced after loss of S. aureus lipoprotein. In conclusion, during S. aureus infection, S. aureus lipoprotein plays a significant role in activating macrophage inflammatory signaling pathways, mediating the secretion of inflammatory mediators, and it is closely associated with the synthesis and secretion of PGE₂. This study offers a theoretical foundation for the clinical use of prostaglandin synthetase inhibitors and non-steroidal anti-inflammatory drugs (NSAIDs) to prevent and treat infections from S. aureus.

The aim of this study was to explore the regulatory role of fatty acid-binding protein 4 (FABP4) on chemokine secretion in Bacillus Calmette-Guérin (BCG) infected macrophages. Using mouse macrophage RAW264.7 as in vitro model, the expression of FABP4 was knocked down by siRNA, combined with BCG infection, and the expression of chemokines were detected by fluorescence quantitative PCR, ELISA and other methods. Subsequently, the function of FABP4 was inhibited by FABP4 inhibitor BMS-309403 in C57BL/6J mice, combined with BCG infection. The levels of lung chemokine secretion were detected by Western blot and ELISA. The lung tissue injury was observed by HE staining. The bacterial load in lung tissue of mice was detected by coated plate method. The results showed that the mRNA expressions of chemokines CCL2, CCL3, CXCL2, CXCL10 and CXCL11 of RAW264.7 macrophages infected with BCG were up-regulated in a time and dose dependent manner compared with the control group. The expression was significantly increased (P < 0.05) when the multiple of infection was 10 MOI at 12 h post infection. Compared with the BCG group, the expression levels of CCL3 (P < 0.001) and CXCL2 (P < 0.01) were significantly down-regulated in FABP4 knockdown combined with the BCG group, while the expression levels of CCL2, CXCL10 and CXCL11 were not significantly different. Studies in mice showed that BMS-309403 reduced the expression of chemokines CCL3 (P < 0.001) and CXCL2 (P < 0.001) in lung tissue and serum of mice, and mitigate the lung tissue injury of C57BL/6J mice after BCG infection. Plate coating found that BMS-309403 significantly increased the content of pulmonary bacteria in mice infected with BCG (P < 0.001). In conclusion, FABP4 promoted the expression of chemokines in RAW264.7 macrophages and mouse lung tissue infected with BCG and clearance of lung bacteria.

The AMPK/SIRT1 pathway plays an important role in the regulation of testicular lactate transport, and the regulatory function of adiponectin on animal reproduction has been gradually proved in recent years. However, how the AMPK/SIRT1 pathway mediates adiponectin to regulate lactate transport in yak sertoli cells is still unclear. Three yak testis samples of different ages (newborn, juvenile, adult and aged) were collected. Western blot, tissue immunofluorescence staining and cell immunofluorescence staining were used to explore the molecular mechanism of the AMPK/SIRT1 pathway mediating adiponectin to promote lactate transport in sertoli cells of yak. Results showed that AMPK, P-AMPK and SIRT1 proteins were expressed in the testis tissue of yaks at different ages, and the relative protein expression levels in the juvenile and aged were significantly higher than those in the newborn and adults (P < 0.01). The distribution of AMPK and SIRT1 proteins was similar in the testis of yaks at different ages, mainly distributed in sertoli cells, leydig cells and spermatogenic cells at all levels. Sertoli cells were treated with various concentrations of adiponectin (0, 5, 10, 20, 50, 100 ng ·mL^-1). When the concentration of adiponectin was 10 ng ·mL^-1, The protein expression of APNR1, AMPK, P-AMPK and SIRT1 was significantly activated (P < 0.01), while the protein expression of MCT1 was the highest, and the lactate release was the highest. The protein expression of AMPK was significantly inhibited by Compound C (P < 0.01), an AMPK protein inhibitor. But the protein expression levels of AMPK, P-AMPK and MCT1 were significantly increased when adiponectin and Compound C were treated together (P < 0.01). The results indicate that APN plays a role in the development of the yak testis binding with APNR1. This study provides some theoretical basis for promoting yak production and reproduction.

The reports of carbapenem-resistant Klebsiella pneumoniae (CRKP) are increasing annually, and tigecycline has become the last line of defense for treating carbapenem-resistant Klebsiella pneumoniae (CRKP) infections, this article presents a preliminary study on the mechanism of tigecycline resistance in three strains of carbapenem-resistant Klebsiella pneumoniae. Broth microdilution method was used to determine the sensitivity of CRKP to tigecycline and evaluate the effect of efflux pump inhibitor, PAβN, on drug resistance. Combined with the results of the previous whole genome sequencing, polymerase chain reaction (PCR) testing was employed to validate the presence of genes and corresponding regulatory factors, porins (acrAB-tolC, oqxAB, msbA, kexD, kdeA, kpnEF, kpnGH, Ompk37, OmpA, ramA, ramR, marA, rarA, acrR, tet(X4), tetA) associated with tigecycline resistance, and differences in gene expression levels between resistant and sensitive strains were detected by real-time fluorescence quantitative PCR. In vitro drug susceptibility experiments showed that the three CRKP strains KP30535, KP30845 and KP30727 were resistant, intermediate and sensitive to tigecycline respectively. In vivo addition of PAβN increased the resistance of strain to tigecycline. The results of real-time quantitative fluorescence PCR showed that the transcription levels of acrAB, kpnGH and ramA in resistant strain KP30535 and intermediate strain KP30845 were significantly higher (P < 0.05) than those of the control strain ATCC13883, and the transcription level of kpnE in KP30535 was extremely higher (P < 0.01). The transcription levels of acrB, ramA and ramR in KP30727 were significantly higher (P < 0.05) than control. The transcription of porins Ompk37 and OmpA in the three strains were markedly lower (P < 0.001) than control. The results of Spearman correlation analysis showed that acrAB, kpnGH, kexD and the porin OmpA were associated with the antimicrobial resistance phenotype of the strain to tigecycline ($|r|$ ≥0.6). The preliminary research results indicate that the different expression of acrAB, kpnGH, kexD, and porin OmpA may be important factors affecting the resistance of CRKP to tigecycline in this study, which can provide reference for further in-depth research.

P1 phage-plasmid has garnered much attention as a carrier of antibiotic resistance genes in Enterobacteriaceae. This experiment was conducted to study the P1 phage-plasmid carrying antibiotic resistance genes whether have biological characteristics such as induction and further transduction. The biological characteristics of P1-CTX phage-plasmid carrying the third-generation cephalosporin resistance gene bla_CTX-M-27 in Salmonella were studied, including phage titer, optimal multiplicity of infection, one-step growth curve, temperature and acid-alkali stability. The results showed that P1-CTX phage-plasmid could induce complete phage with cleavage ability, the titer was 10⁶ PFU·mL^-1, and the optimal multiplicity of infection was 0.01. P1-CTX phage had good activity below 50 ℃ and could tolerate strong alkali but not strong acid. It can be infected with Salmonella and Escherichia coli. It has no effect on host growth and is very stable. In conclusion, the above results indicated that P1-CTX phage-plasmid had normal phage biological characteristics and could carry drug resistance genes through transduction and spread horizontally with good stability.

The purpose of this study is to investigate the clinical therapeutic effect of a novel acellular bioengineering cornea (ABC) with eccentric lamellar keratoplasty on deep corneal injury in cats and the regulatory mechanism of related cytokines during the healing process. A corneal eccentric alkali burn model in 36 healthy adult local cats was established, and the model animals were randomly divided into three groups: ABC transplantation group (ABCTs group), corneal limbal conjunctival transplant group (CLCTs group), and control group. Evaluate the clinical efficacy and role of ABC eccentric deep lamellar keratoplasty through slit lamp examination, measurement of intraocular pressure and tear volume, corneal opacity and fluorescein staining score, optical coherence tomography (OCT) and histopathology. The corneal transparency of the ABCTs group was superior to other groups at all time-points, and the difference in corneal opacity score was extremely significant (P < 0.01). The intraocular pressure and tear volume of the three groups after surgery were within the normal physiological range, and the fluorescein staining scores showed an overall decreasing trend. However, the corneal re-epithelialization time in the ABCTs group was significantly earlier than that in the other groups (P < 0.01). OCT examination showed that the ABCTs group had earlier fusion of the graft with the host corneal stroma compared to the CLCTs group. There was no significant difference in corneal thickness between the ABCTs group and the normal cornea at 90 days after surgery (P>0.05), while the CLCTs group showed a significant decrease in corneal thickness (P < 0.01). Histological observation revealed that the ABCTs group had fewer inflammatory cells in corneal tissue compared to the CLCTs group, and the arrangement of corneal collagen was more regular. ABC transplantation can effectively treat cat eccentric corneal injury and provide excellent corneal transparency. ABC may promote corneal repair and transparency recovery by reducing collagen fibers and formation of scars.

To explore whether cadmium can induce oxidative stress in the cerebral cortices by affecting the intestinal flora of rats, twenty 21-day-old female Wistar rats were randomly divided into control group (Con group) and cadmium group (Cd group) and pre-fed for 1 week. The rats in the Cd group were given cadmium chloride (CdCl₂) at a dose of 10 mg per kg of body weight by intragastric administration every day, while the rats in the Con group were given double distilled water at the same dose by intragastric administration (i.g.) every day. After 4 weeks, the fresh feces of the rats were collected to make fecal bacteria suspension, and then the cerebral cortices of the rats were dissected. In addition, twenty 21-day-old female Wistar rats were given mixed antibiotics for 1 week to construct a pseudo-aseptic model, and were randomly divided into fecal microbiota transplantation control group (FMTCon group) and fecal microbiota transplantation cadmium group (FMTCd group). The rats in the FMTCon group were given the above-mentioned fecal suspension of the rats in the Con group at a dose of 10 mL per kg of body weight by i.g. every day, and the rats in the FMTCd group were given the above-mentioned fecal suspension of the rats in the Cd group at a dose of 10 mL per kg of body weight by i.g. every day. After 4 weeks of treatment, the cerebral cortices of rats were dissected and collected. The contents of malondialdehyde (MDA) and reduced glutathione (GSH), the activities of total superoxide dismutase (T-SOD) and catalase (CAT) and the total antioxidant capacity (T-AOC) were detected by colorimetry. The protein expressions of nuclear factor E2-related factor 2 (Nrf2) and NADH quinone dehydrogenase 1 (NQO-1) were detected by Western blot. The results showed that compared with the Con group, the contents of MDA were significantly increased (P < 0.05), the contents of GSH, the activities of CAT and T-SOD, and the protein expressions of T-AOC, Nrf2 and NQO-1 were significantly decreased (P < 0.05) in the cerebral cortices of Cd group rats. Compared with FMTCon, the contents of MDA were significantly increased (P < 0.05), the content of GSH, the activities of CAT, the protein expressions of Nrf2 and NQO-1 were significantly decreased (P < 0.05), and the activities of T-SOD and T-AOC were decreased, but there were no significant difference (P>0.05) in the cerebral cortices of FMTCd group rats. The results suggested that cadmium could induce oxidative stress in the cerebral cortices by affecting the intestinal flora of rats.

This study aims to establish a preliminary triplex PCR assay capable of simultaneously detecting porcine endogenous retroviruses (PERV) in the pig genome and differentiating the three PERV subtypes: PERV-A, PERV-B, and PERV-C. Specific primers were designed based on the envelope (env) gene of different PERV subtypes. The method was validated for specificity, sensitivity and reproducibility after optimization of the reaction conditions and the reaction system. The results showed that the triplex PCR method specifically amplified all three PERV subtypes. The detection limits for the plasmid standards of PERV-A, PERV-B, and PERV-C were 1.50×10², 1.99×10³, and 1.57×10² copies·μL^-1, respectively. A total of 103 tissue samples were tested using the triplex PCR method and compared with the conventional single PCR method. The positive rates were 100% (103/103) for PERV-A, 100% (103/103) for PERV-B and 54% (56/103) for PERV-C. The compliance rates for the two methods were PERV-A, PERV-B, and PERV-C were 100%, 100%, and 96.6%, respectively. This study successfully developed a highly specific, sensitive, rapid, and convenient triplex PCR assay, which can be used for the simultaneous detection and differential diagnosis of the three PERV subtypes, and provides technical support for the screening of PERV-free porcine-derived donor organs.

The study aims to develop a DNA pseudovirus with full quality control and avoiding plasmid cross-contamination in nucleic acid detection for African swine fever virus (ASFV). The B646L/CD2v/MGF505-1R/MGF360-12L key-genes of ASFV and EGFP gene were co-combined into the baculovirus transfer vector pFastBac^TMDual. The Bacmid pFastBac-EGFP-ASFV was formed by transformation. The Bacmid was transfected into sf21 cells and packaged to produce AcMNPV-EGFP-ASFV. The green fluorescence signal of EGFP protein expressed indicated that AcMNPV-EGFP-ASFV was preparated successfully. Genome traceability analysis of the AcMNPV-EGFP-ASFV showed that the ASFV target gene sequence was met the requirements of current detection methods. The ASFV quality control product is uniform and stable, and is stably stored at -20 ℃ for at least 24 months. The quantification is 4.09×10³ copies·μL^-1 using ddPCR. The preparation of ASFV DNA pseudovirus provides a new technical support for the monitoring of the African swine fever.