本研究旨在探讨饲粮添加异亮氨酸是否可以缓解轮状病毒(RV)感染对断奶仔猪回肠屏障功能的影响。在细胞试验中,用8 mmol/L的L-异亮氨酸处理IPEC-J2细胞24 h;在动物饲养试验中,选取28头健康的21日龄断奶的“杜×长×大”仔猪,采用2×2双因子设计,即饲粮处理(添加1%L-异亮氨酸饲粮或添加0.68%L-丙氨酸饲粮)和RV攻毒(灌服RV或无菌培养液),RV攻毒于试验第15天早上进行。试验期为18 d。结果表明,L-异亮氨酸处理提高了IPEC-J2细胞中黏液蛋白2(mucin 2)、闭锁小带蛋白-1(ZO-1)和闭合蛋白(occludin)的mRNA相对表达量(P <0.05); RV攻毒提高了断奶仔猪平均腹泻指数和血清二胺氧化酶活性(P<0.05),提高了回肠黏膜中RV的非结构蛋白4阳性率,降低了断奶仔猪回肠黏膜中mucin 2、ZO-1和occludin mRNA相对表达量(P<0.05);而饲粮添加异亮氨酸缓解了RV攻毒对断奶仔猪平均腹泻指数、血清二胺氧化酶活性和回肠黏膜mucin 2、ZO-1和occludin mRNA相对表达量的影响(P<0.05),降低了回肠黏膜中RV的非结构蛋白4阳性率。综上所述,在断奶仔猪的饲粮中补充1%异亮氨酸可以预防RV诱导发生的腹泻,而这一作用与其可改善回肠屏障功能有关。
[学术文献] Inter-correlated gut microbiota and SCFAs changes upon antibiotics exposure links with rapid body-mass gain in weaned piglet model 进入全文
The risk of overweight or obesity in association with early exposure of antibiotics remains an important public issue for health-care of children. Low-dose antibiotics (LDA) have been widely used to enhance growth rate of pigs, providing a good animal model to study the underlying mechanism. In present study, 28 female piglets, weaned at 21 d, were randomly classified into two groups, receiving either a control diet or a diet supplemented with LDA for 4 weeks. The total bacterial load and intestinal microbiota were determined by qPCR and 16S rRNA amplicon sequencing. UPLC-QTRAP-MS/MS and RNA-seq were further used to determine the colonic SCFAs and transcriptomes. Results showed that LDA significantly increased growth rate and food intake. The F/B index, Methanosphaera species, and the pathway of “carbohydrate metabolism” were improved by LDA exposure, indicating the better carbohydrate degradation and energy utilization. Furthermore, correlation analysis indicated the microbial community contributing to SCFAs production was enriched upon LDA exposure, associating with increased concentrations of short-chain and branched-chain fatty acids (caproate, 2-methyl butyrate and 4-methyl valerate). A multivariate linear fitting model analysis highlighted that caproate was positively correlated with two genera ( Faecalibacterium and Allisonella ) and four differentially expressed genes ( ZNF134 , TBX5 , NEU4 and SEMA6D ), which were all significantly increased upon LDA exposure. Collectively, our study indicates that the growth-promoting effect of LDA exposure in early life is associated with the shifts of colonic microbiota to increase utilization of carbohydrates and energy, enhanced SCFAs production and colonic functions.
Interactions between the bacteria and fungi in the gut microbiome can result in altered nutrition, pathogenicity of infection, and host development, making them a crucial component in host health. Associations between the mycobiome and bacteriome in the piglet gut, in the context of weaning, remain unknown. Weaning is a time of significant stress, dietary changes, microbial alterations, and a predisposition to infection. The loss of animal health and growth makes potential microbial interventions of interest to the swine industry. Recent studies have demonstrated the diversity and development of the microbiome in the gastrointestinal (GI) tract of piglets during weaning, resulting from the dietary and physiological changes. Despite these advances, the role of the mycobiota in piglet health and its contribution to overall microbiome development remains mostly unknown. In this study we investigated the bacteriome and the mycobiome after weaning in the GI tract organs and feces from 35-day old piglets. Following weaning, the α-diversity and amplicon sequence variants (ASVs) counts of the bacteriome increased, proximally to distally, from the stomach to the feces along the GI tract, while the mycobiome α-diversity and ASV counts were highest in the porcine stomach. β-diversity analyses show distinct clusters based on organ type in the bacteriome and mycobiome, but dispersion remained relatively constant in the mycobiome between organ/fecal sites. Bacteroidetes, Firmicutes, and Epsilonbacteraeota were the most abundant bacterial phyla present in the GI tract and feces based on mean taxonomic composition with high variation of composition found in the stomach. In the mycobiome, the dominant phyla were Ascomycota and Basidiomycota, and the stomach mycobiome did not demonstrate the same high level of variation observed in the bacteriome. Potential interactions between genera were found in the lower piglet GI bacteriome and mycobiome with positive correlations found between the fungus, Kazachstania , and several bacterial species, including Lactobacillus . Aspergillus demonstrated negative correlations with the short chain fatty acid-producing bacteria Butyricoccus , Subdoligranulum , and Fusicatenibacter . This study demonstrates the distinct colonization dynamics between fungi and bacteria in the GI tract and feces of piglets directly following weaning and the potential interactions of these microbes in the porcine gut ecosystem.
[前沿资讯] Annual EUSR Reports on Zoonoses and Food-borne Outbreaks and Antimicrobial Resistance. Customer feedback – final report 进入全文
EFSA monitors the occurrence of food-borne zoonoses, zoonotic agents and antimicrobial resistance in humans, animals and food in collaboration with the ECDC as defined in the Zoonoses Directive 2003/99/EC. As part of this responsibility, EFSA annually publishes two European Summary Reports (EUSRs) assessing the trends and sources of zoonoses, zoonotic agents and food-borne outbreaks (zoonoses) and antimicrobial resistance (AMR) in zoonotic agents. This report brings together feedback from EFSA’s stakeholders and customers on the efficacy, efficiency, relevance, added value, coherence and timeliness of the annual EUSR on zoonoses and food-borne outbreaks and of the annual EUSR on antimicrobial resistance in collecting data and supporting informed risk assessment and risk management.