This study explored the effects of high-density rearing of pregnant ewes on the intestinal microbiota of their offspring. A total of 40 small-tailed Han sheep were distributed into two groups randomly including the high-density group (1 sheep/m(2)) and the control/ low-density group (1 sheep/2m2). Fecal samples from ewes and offspring were collected for high-throughput sequencing and multiple-significance analysis. We uncovered the response of gut microbiota in ewes and offspring to different rearing densities. The number of potentially harmful bacteria (Ralstonia pickettii, Ruegeria, Rhodobacteraceae, etc.) was increased in high-density groups, while the abundance of several probiotics (Oscillibacter, Akkermansia, Ruminococcaceae-UCG-010, etc.) was found significantly lesser than that of the control group (P<0.05). In addition, gut microbiota in the high-density groups exhibited more variability with age, indicating that an increase in the housing density has a significant correlation. Taken together, improper increase in the rearing density of pregnant sheep can harm themselves and their offspring, which not only fails to improve economic benefits but also produces harmful effects. This study may provide new ideas for healthy and sustainable sheep reproduction and farming.

Tight junctions (TJs) are the key determinant of barrier function in the mammary gland, with their disruption being associated with the pathogenesis and progression of mastitis, especially in the case of Staphylococcus aureus (S. aureus) infection. This study investigated whether selenium (Se) could attenuate S. aureus-induced mastitis by inhibiting inflammation and protecting mammary gland TJs in mice. The expression profiles of S. aureus-infected gland tissues derived from the gene expression omnibus dataset were analyzed. We found cytokine production, cell junctions, the nuclear transcription factor-κB (NF-κB) signalling pathway, and inflammatory responses associated with the differentially expressed genes, as revealed by Gene Ontology (GO) and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analyses. Se reduced the mRNA expression and production of inflammatory cytokines, including tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6), and decreased phosphorylation levels of the NF-κB complex. Moreover, Se alleviated structural damage and microvillus injury in mammary glands. Immunohistochemical staining revealed that Se increased the expression of Claudin-3; Western blot analysis revealed increased protein levels of Occludin and Tricellulin in the group supplemented with dietary Se. In summary, Se counteracted TJ disruption and attenuated NF-κB-mediated inflammatory responses in S. aureus-infected mouse mammary glands.

Lycium barbarums are traditionally used as a homology of medicinal plants in China with a potent role in metabolism and immunomodulation. The current study was performed to explore the attenuation effect and microbiota regulation of Lycium barbarum polysaccharide (BLBP) on lipopolysaccharide (LPS)-induced intestine damage in mice. A total of 70 mice were randomly divided into five groups; negative control (GA), LPS (GB), both treated with an equal volume of normal saline, and BLBP treatment groups GC (100 mg/kg), GD (200 mg/kg), and GE (400 mg/kg) via gavage for 19 days. On Day 19, mice in groups GB, GC, GD, and GE were treated with 10 mg/kg LPS for 24 h and euthanized to collect intestine samples for pathological examination and microbiota sequencing. The results showed a non-significant difference in body weight gain among the five mouse groups; however, mice in the GC and GE groups showed decreased weight gain. An H&E examination revealed that the integrity of intestinal villi was destroyed by LPS, while BLBP supplement alleviated intestinal damage with an increase in villus height and a decrease in crypt depth. A total of over 59,000, 40,000, 50,000, 45,000, and 55,000 raw sequences were found in groups GA, GB, GC, GD, and GE, respectively. LPS challenge decreased alpha diversity indexes significantly ( p < 0.05), while a non-significant difference was found between different BLBP treatment groups and the GA group. A total of 8 phyla and 13 genera were found among five mouse groups, and BLBP partly restored the bacterial abundance in mice. LPS changed 282 metabolic pathways in KEGG L2, 77 metabolic pathways in KEGG L3, and 205 metabolic pathways in MetaCyc, respectively. The BLBP-supplemented groups, especially GE, showed reverse effects on those metabolic pathways. The current study revealed that BLBP can effectively decrease intestinal damage through the regulation of intestinal microbiota, which may provide new insights for the prevention of intestinal disease using food and medicine homologous of Lycium ruthenicum .

Inappropriate management practices of domestic animals during pregnancy can be potential stressors, resulting in complex behavioural, physiological and neurological consequences in the developing offspring. Some of these consequences can last into adulthood or propagate to subsequent generations. We systematically summarized the results of different experimental patterns using artificially increased maternal glucocorticoid levels or prenatal maternal physiological stress paradigms, mediators between prenatal maternal stress (PMS) and programming effects in the offspring and the effects of PMS on offspring phenotypes in sheep. PMS can impair birthweight, regulate the development of the hypothalamic-pituitary-adrenal axis, modify behavioural patterns and cognitive abilities and alter gene expression and brain morphology in offspring. Further research should focus on the effects of programming on gene expression, immune function, gut microbiome, sex-specific effects and maternal behaviour of offspring, especially comparative studies of gestational periods when PMS is applied, continual studies of programming effects on offspring and treatment strategies that effectively reverse the detrimental programming effects of prenatal stress.

Staphylococcus aureus is a critical pathogen causing serious mastitis with huge economic losses in bovines. To reveal drug-resistant genes, a complete genome sequence of a multi-drug-resistant bacterium S. aureus derived from bovine mastitic milk was performed via High-throughput sequencing. Results revealed that the genome length of current S. aureus was 2.85 Mbp consisting of 2656 coding sequence genes, 60 tRNA, 19 rRNA, and 5 genomic islands. Functional annotation of S. aureus encoded proteins showed that 2090 (COG), 1586 (KEGG), 1600 (GO), 2648 (Refseq), 2300 (Pfam), 964 (SwissProt), and 1826 (TIGRFAMs) proteins were annotated. Antibiotic-resistant genes of tet, mepR, mepA, mgrA, norA, blaZ, arlS, arlR and LmrS in S. aureus genome were found via CARD annotation. More than 60 bacterial virulence factors including commonly known clfA, hla, hlb, fnbB, fnbA in S. aureus genome were uncovered through VFDB annotation. The current study may contribute towards effective treatment and developing new antibiotics against mastitis caused by S. aureus.

Manganese is one of the essential trace elements in the process of animal growth and develop-ment,which affects animal immunity,metabolism,reproduction and bone development,and participates in the metabolism of various substances as an enzyme composition and enzyme activation factor in ani-mals.In this paper,the circulation process of manganese in ruminants and its influence on sheep physiol-ogy and production were reviewed,in order to provide some theoretical reference for the application of manganese in sheep production.

BACKGROUND:Yak (Bos grunniens) mainly inhabiting Tibet Plateau, displayed a high incidence of diarrhea due to harsh living environment and nutritional deficit. Gut microbial community has been reported to be closely related to many diseases including diabetes, obesity and inflammatory bowel disease, but information regarding diarrheic influence on gut microbiota in yaks remains scarce. Here, this study was performed to investigate the gut bacterial and fungal alternations of diarrheic yaks.RESULTS:Results revealed that the gut bacterial and fungal communities of diarrheic yaks showed a distinct decline in alpha diversity, accompanied by significant shifts in taxonomic compositions. Specifically, diarrhea caused a distinct increase in the relative abundance of 1 phylum and 8 genera as well as a distinct decrease in 3 phyla and 30 genera. Fungal taxonomic analysis indicated that the relative richness of 1 phylum and 2 genera dramatically increased, whereas the relative richness of 2 phylum and 43 genera significantly decreased during diarrhea. Surprisingly, 2 bacterial genera and 5 fungal genera even cannot be detected in the gut microbiota of diarrheic yaks.CONCLUSIONS:In summary, this study indicated that the gut bacterial and fungal compositions and diversities of yaks altered significantly during diarrhea. Moreover, these findings also contribute to understanding the gut microbial composition and diversity of yaks and developing strategies to alleviate and prevent diarrhea from gut microbial perspective.

Abstract In this study the protective effect of dietary Selenium during pregnancy on the acute mammary injury induced by S. aureus were observed. Eighty BALB/c pregnant mice were randomly divided into four groups: Control group (CG; Se-deficient basal diet during pregnancy without S. aureus infection; n = 20), Negative control (NG; 0.2 mg/kg Se-supplemented diet during pregnancy without S. aureus infection; n = 20), Positive group (PG; Se-deficient basal diet during pregnancy and infected with S. aureus four days after pregnancy; n = 20) and Treatment group (TG; 0.2 mg/kg Se-supplemented diet during pregnancy and infected with S. aureus. four days after pregnancy; n = 20). 24 h after infection, all mice were euthanized and the mammary tissues were sampling. Pathological section and scanning electron microscope were used to observe the pathologic injury in mammary gland, 54146 genes were detected by high throughput sequencing to identify the differentially expressed gene, ELISA was used to determine the expression level of IL-1β and TNF-α. Results shown that the mammary tissue structure were damaged by S. aureus, after selenium treatment the acute injury lightened, meanwhile 24434 were detected differentially expressed after S. aureus infection, which mainly regulate T cell activation, keratinization, cytokine production. Whereas only 20467 differentially expressed genes were detected in TG, in which genes code T cell activation and cytokine production were marked downregulated and gene code cell adhesion was upregulated. furthermore, selenium treatment significantly decreased the expression level of IL-1β and TNF-α induced by S. aureus. In conclusion, selenium played a protective effect on the acute injury in S. aureus-infected mouse mammary gland.

Staphylococcus aureus is a leading source of foodborne poisoning in the human population also critically severe mastitis in livestock. A total of 671 serum samples were collected and tested through ELISA assays. The results revealed that the total prevalence of S. aureus infection in dairy cattle was 29.1% (95% CI: 25.6-32.7). In different farms, the prevalence ranged from 13.9% (95% CI: 8.8-20.5) to 36.6% (30.4-43.2). Similarly, the mean sero-prevalence was 17.0% (13.1-21.4) and 41.6% (36.3-47.2) in male and female animals, respectively. However, at different ages, the mean prevalence of Staphylococcus aureus was found to be 14.3% (7.4-24.1) to 38.5% (30.8-46.6). Although in different years, the sero-prevalence was 27.5% (22.2-33.4) in 2019, 19.6% (13.7-26.7) in 2020 and 36.5% (30.6-42.7) in 2021. According to conditional stepwise logistic regression analysis, different farms, gender, age and year were observed as the critical risk factors affecting the prevalence. Our results may contribute to development of prevention and control strategies against this zoonotic pathogen in farm animals in this region.

Mastitis is an economically important disease in the dairy industry, which is caused by various infectious pathogens. There is limited information known about the situation of drug resistance and virulence factors of Staphylococcus aureus (S. aureus) in mastitis bovine milk in Anhui. Therefore, a total of 125 fresh milk samples from clinically mastitis-positive bovine animals were collected. The bacteria pathogens were identified via bacterial culture, Gram staining, biochemical analysis, DNA extraction, 16s rRNA amplification, and phylogenetic analysis. Drug resistance analyses were performed through drug-resistant genes and virulence genes amplification. Results showed that a total of 24.8% (31/125) bacterial isolates were isolated and identified as S. aureus by Gram straining, biochemical reactions, and 16 s rRNA genes blasting. Multiple sequence alignment analysis found that the current isolates were highly similar (96.9–100.0%) to previous isolates. Phylogenetic analysis demonstrated that S. aureus was similar with MK809241.1 isolated from food in China and wCP030426.1 isolated from a person in the United States. The bacterial isolates were detected resistant to 11 antibiotics, such as Penicillin G, SXT, Ciprofloxacin, Norfloxacin, Polymyxin B, Levofloxacin, Chloramphenicol, Clindamycin, Clarithromycin, Erythromycin, and Spectinomycin. Drug-resistant genes of blaZ, ermC, rpoB, and ant (4')-la were successfully amplified. Virulence genes of hla, nuc, clfa, and eta were found in S. aureus bacteria. The current study isolated S. aureus from milk samples and revealed its drug-resistant situation, drug-resistant genes, and virulence genes. Hence, regular monitoring of S. aureus in milk samples from dairy cows may contribute to the prevention and treatment of public health concerns causing bacteria in this region.

In this study, the regulation effects of selenium (Se) on the expression of pyrin domain-containing protein (NLRP) 3 inflammasome and reactive oxygen species (ROS) in bovine mammary epithelial cells (bMECs) infected by Staphylococcus aureus (S. aureus) were detected. bMECs were treated with 8 μmol/L Na2SeO3 for 12 h before infection with S. aureus for 2 h. Through flow cytometry, Western blot, and qRT-PCR analysis, the expression of ROS and NLRP3 imflammasome was detected. Results showed Se significantly reduced the ROS level in bMECs; at the same time, the expressions of NLRP3, ASC, caspase-1, Pro-IL-1β, and IL-1β were also decreased. In conclusion, Se inhibits S. aureus-induced inflammation by suppressing the activation of NLRP3 inflammasome and ROS in bMECs.

为探究硒(Se)对金黄色葡萄球菌(S.aureus)感染的奶牛乳腺上皮细胞(bMECs) Nod2/MAPK/mTORs信号通路的调控机制,本研究首先用不同浓度硒(2 μmol/L、4μmol/L和8μmol/L)对bMECs进行预孵育,12 h后再经S.aureus感染处理.分别于感染后6h、8h和10h收集bMECs提取其RNA,应用qPCR方法检测bMECs中Nod2、RIP2、JNK、AKT、mTOR、IL-8和IL-10 mRNA的转录水平.结果 显示,S.aureus能显著提高bMECs中Nod2、RIP2、JNK、AKT和mTOR mRNA的转录水平(p＜0.01),而硒能不同程度的抑制这些因子mRNA的转录水平(p＜0.05或p＜0.01).此外,S.aureus能显著或极显著提高bMECs中IL-8和IL-10 mRNA的转录水平(p＜0.05或p＜0.01),而硒对S.aureus感染的bMECs中IL-8和IL-10mRNA的转录水平有明显抑制作用(p＜0.05或p＜0.01).上述结果表明,硒可通过抑制Nod2/MAPK/mTORs信号通路的转导而减轻S.aureus诱导的bMECs的炎症反应.本研究为阐明硒能减轻S.aureus诱导的bMECs炎症反应的机制提供试验依据.