Department of Animal Science, The Pennsylvania State University, University Park, PA, USA; One Health Microbiome Center, The Pennsylvania State University, University Park, PA, USA.
Department of Animal Science, The Pennsylvania State University, University Park, PA, USA; One Health Microbiome Center, The Pennsylvania State University, University Park, PA, USA; Department of Biology, The Pennsylvania State University, University Park, PA, 16802, USA.
Poult Sci. 2024 May;103(5):103604. doi: 10.1016/j.psj.2024.103604. Epub 2024 Mar 4.
The poultry industry is evolving towards antibiotic-free production to meet market demands and decelerate the increasing spread of the antimicrobial resistance. The growing need for antibiotic free products has challenged producers to decrease or completely stop using antimicrobials as feed supplements in broiler diet to improve feed efficiency, growth rate, and intestinal health. Natural feed additives (e.g., probiotics and phytobiotics) are promising alternatives to substitute antimicrobial growth promoters. The goal of our study was to characterize the effects of a Probiotic and an Essential Oils blend on broilers' performance and perform a time-series analysis to describe their excreta microbiome. A total of 320 Cobb 500 (1-day-old) chicks were raised for 21 d in 32 randomly allocated cages. Treatments consisted of 4 experimental diets: a basal diet, and a basal diet mixed with an Antibiotic (bacitracin methylene disalicylate), an essential oils blend (oregano oil, rosemary, and red pepper), or a Probiotic (Bacillus subtilis). Body weight (on 1, 10, and 21d), and feed intake (10d and 21d) were recorded and feed conversion ratio was calculated. Droppings were collected daily (1-21d) to characterize broilers' excreta microbiota by targeted sequencing of the bacterial 16S rRNA gene. The Probiotic significantly improved feed conversion ratio for starter phase 1 to 10d (P = 0.03), grower phase 10 to 21d (P = 0.05), and total period 1 to 21d (P = 0.01) compared to the Antibiotic. Feed supplements did not affect alpha diversity but did impact microbial beta diversity (P < 0.01). Age also impacted microbiome turnover as differences in alpha and beta diversity were detected. Furthermore, when compared to the basal diet, the probiotic and antibiotic significantly impacted relative abundance of Bifidobacterium (log2 fold change -1.44, P = 0.03), Intestinimonas (log2 fold change 0.560, P < 0.01) and Ligilactobacillus (log2 fold change -1.600, P < 0.01). Overall, Probiotic supplementation but not essential oils supplementation positively impacted broilers' growth performance by directly causing directional shifts in broilers' excreta microbiota structure.
家禽业正在朝着无抗生素生产方向发展，以满足市场需求并减缓抗菌药物耐药性的不断蔓延。对无抗生素产品的需求不断增长，这使得生产者面临挑战，需要减少或完全停止在肉鸡饲料中使用抗生素作为饲料添加剂，以提高饲料效率、生长速度和肠道健康。天然饲料添加剂（例如益生菌和植物提取物）是替代抗菌生长促进剂的有前途的选择。我们的研究目的是描述益生菌和精油混合物对肉鸡生产性能的影响，并进行时间序列分析以描述其粪便微生物组。总共 320 只 Cobb 500（1 日龄）小鸡在 32 个随机分配的笼子中饲养 21 天。处理包括 4 种实验日粮：基础日粮，以及基础日粮与抗生素（杆菌肽甲烯二水杨酸酯）、精油混合物（牛至油、迷迭香和红辣椒）或益生菌（枯草芽孢杆菌）混合。记录体重（1、10 和 21 天）和采食量（10 天和 21 天），并计算饲料转化率。每天（1-21 天）收集粪便，通过靶向测序细菌 16S rRNA 基因来表征肉鸡粪便微生物群。与抗生素相比，益生菌显著提高了 1 至 10 天的育雏期（P = 0.03）、10 至 21 天的生长期（P = 0.05）和 1 至 21 天的总期（P = 0.01）的饲料转化率。饲料添加剂不影响 alpha 多样性，但会影响微生物 beta 多样性（P <0.01）。年龄也会影响微生物组的周转率，因为在 alpha 和 beta 多样性方面都检测到了差异。此外，与基础日粮相比，益生菌和抗生素显著影响双歧杆菌（log2 倍变化-1.44，P = 0.03）、肠菌属（log2 倍变化 0.560，P <0.01）和 ligilactobacillus（log2 倍变化-1.600，P <0.01）的相对丰度。总体而言，益生菌的补充而不是精油的补充通过直接引起肉鸡粪便微生物组结构的定向变化，对肉鸡的生长性能产生了积极影响。
