Pig Development Department, Teagasc Grassland Research and Innovation Centre, Moorepark, Cork, Ireland.
Grupo de Genómica y Mejora Animal, Departamento de Genética, Facultad de Veterinaria, Universidad de Córdoba, Córdoba, Spain.
Front Cell Infect Microbiol. 2024 Feb 7;14:1354449. doi: 10.3389/fcimb.2024.1354449. eCollection 2024.
Post-weaning diarrhoea (PWD) is a multifactorial disease that affects piglets after weaning, contributing to productive and economic losses. Its control includes the use of in-feed prophylactic antibiotics and therapeutic zinc oxide (ZnO), treatments that, since 2022, are no longer permitted in the European Union due to spread of antimicrobial resistance genes and pollution of soil with heavy metals. A dysbiosis in the microbiota has been suggested as a potential risk factor of PWD onset. Understanding pig's microbiota development around weaning and its changes in response to ZnO and antibiotics is crucial to develop feasible alternatives to prophylactic and metaphylactic antimicrobial use.
This study used shotgun metagenomic sequencing to investigate the environmental and faecal microbiota on 10 farms using (Treated) or not using (ZnO-free) in-feed antibiotics and ZnO during the first 14 days post-weaning (dpw). Environmental samples from clean pens were collected at weaning day (0dpw), and faecal samples at 0, 7 and 14dpw. Diarrhoeic faecal samples were collected at 7dpw when available.
The analysis of data revealed that the faecal microbiota composition and its functionality was impacted by the sampling time point (microbiota maturation after weaning) but not by the farm environment. Treatment with antibiotics and ZnO showed no effects on diversity indices while the analyses of microbiota taxonomic and functional profiles revealed increased abundance of taxa and metabolic functions associated with or different species of . on the Treated farms, and with and on the ZnO-free farms. The analysis of diarrhoea samples revealed that the treatment favoured the microbiota transition or maturation from 0dpw to 14dpw in Treated farms, resembling the composition of healthy animals, when compared to diarrhoea from ZnO-free farms, which were linked in composition to 0dpw samples.
The results provide a comprehensive overview of the beneficial effects of ZnO and antibiotics in PWD in the microbiota transition after weaning, preventing the overgrowth of pathogens such as pathogenic and revealing the key aspects in microbiota maturation that antibiotics or ZnO alternatives should fulfil.
断奶后腹泻（PWD）是一种多因素疾病，会影响断奶后的仔猪，导致生产和经济损失。其控制包括使用饲料预防性抗生素和治疗性氧化锌（ZnO），但自 2022 年以来，由于抗微生物耐药基因的传播和土壤重金属污染，欧盟已不再允许使用这些药物。微生物群失调被认为是 PWD 发病的一个潜在危险因素。了解仔猪在断奶前后的微生物群发育及其对 ZnO 和抗生素的变化，对于开发可行的替代预防性和治疗性抗菌药物至关重要。
本研究使用 shotgun 宏基因组测序技术，在断奶后第 14 天（14dpw）前，对使用（处理组）或不使用（无 ZnO 组）饲料中抗生素和 ZnO 的 10 个农场的环境和粪便微生物群进行了研究。在断奶日（0dpw）收集清洁畜栏的环境样本，在 0、7 和 14dpw 时收集粪便样本。在 7dpw 时收集腹泻粪便样本。
数据分析表明，粪便微生物群组成及其功能受采样时间点（断奶后微生物群成熟）的影响，但不受农场环境的影响。抗生素和 ZnO 的处理对多样性指数没有影响，而对微生物群分类和功能谱的分析显示，在处理组农场中，与 或不同种属相关的分类群和代谢功能的丰度增加，而在无 ZnO 组农场中，与 和 相关的分类群和代谢功能的丰度增加。对腹泻样本的分析表明，与无 ZnO 组相比，处理组有利于从 0dpw 到 14dpw 的微生物群过渡或成熟，与健康动物的组成相似，而无 ZnO 组的组成与 0dpw 样本相关。
结果全面概述了 ZnO 和抗生素在 PWD 中的有益作用，即在断奶后微生物群过渡中预防了病原菌（如致病性 ）的过度生长，并揭示了抗生素或 ZnO 替代品应满足的微生物群成熟的关键方面。
