Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec J2S 2M2 Canada; Chaire de recherche en salubrité des viandes (CRSV), Université de Montréal, Saint-Hyacinthe, Québec J2S 2M2 Canada; Regroupement FRQ-NT Op+Lait, Saint-Hyacinthe, Québec J2S 2M2 Canada.
Département de Pathologie et Microbiologie, Faculté de Médecine Vétérinaire, Université de Montréal, Saint-Hyacinthe, Québec J2S 2M2 Canada; Regroupement FRQ-NT Op+Lait, Saint-Hyacinthe, Québec J2S 2M2 Canada.
J Dairy Sci. 2022 Jan;105(1):389-408. doi: 10.3168/jds.2021-20523. Epub 2021 Oct 14.
Recycled manure solids (RMS) bedding is an alternative bedding option that is growing in popularity on Canadian dairy farms. However, the microbiological characteristics and production of RMS bedding are poorly documented under on-farm conditions in eastern Canada. This bedding could support the presence of pathogens and could have an effect on cow and human health. The aim of this study was to describe the RMS microbiota when used under dairy cows and compare it with straw bedding. Unused and used bedding from 27 RMS and 61 straw-bedded dairy farms were collected and compared using 16S amplicon sequencing, bacterial counts, and Salmonella spp. and Listeria monocytogenes detection. Microbiota composition of unused RMS and unused straw were different. After use, both bedding microbiota were similar in their bacterial composition, structure, and diversity. Unused RMS generally contained higher bacterial counts than did unused straw, except for Klebsiella spp. counts. Salmonella spp. and L. monocytogenes were more frequently detected in unused RMS (Salmonella spp.: 11%; L. monocytogenes: 30%), than in unused straw (Salmonella spp.: 0%; L. monocytogenes: 11%). Finally, 2 RMS production systems (extraction of the liquid fraction followed by maturation in an opened or enclosed container vs. in a heap) did not influence the microbiota richness and bacteria distribution (α-diversity), but did influence the microbiota structure (β-diversity). In conclusion, animal and human pathogens were found in greater numbers and more frequently in unused RMS than unused straw, and this could eventually affect dairy cow or human health.
再生粪肥固体（RMS）垫料是一种替代垫料选择，在加拿大奶牛场越来越受欢迎。然而，在加拿大东部的农场条件下，RMS 垫料的微生物特征和生产情况记录很少。这种垫料可能会支持病原体的存在，并可能对奶牛和人类健康产生影响。本研究的目的是描述奶牛使用 RMS 垫料时的 RMS 微生物群，并将其与秸秆垫料进行比较。从 27 个 RMS 和 61 个秸秆垫料的奶牛场收集未使用和使用的垫料，并使用 16S 扩增子测序、细菌计数以及沙门氏菌和单增李斯特菌检测进行比较。未使用的 RMS 和未使用的秸秆的微生物群组成不同。使用后，两种垫料的微生物群在细菌组成、结构和多样性方面相似。未使用的 RMS 通常比未使用的秸秆含有更高的细菌计数，除了克雷伯氏菌计数。未使用的 RMS 中更频繁地检测到沙门氏菌和单增李斯特菌（沙门氏菌：11%；单增李斯特菌：30%），而未使用的秸秆中未检测到（沙门氏菌：0%；单增李斯特菌：11%）。最后，2 种 RMS 生产系统（提取液体部分，然后在开放式或封闭式容器中成熟或在堆肥中成熟）不会影响微生物群丰富度和细菌分布（α多样性），但会影响微生物群结构（β多样性）。总之，在未使用的 RMS 中发现了更多数量和更频繁的动物和人类病原体，这可能最终会影响奶牛或人类的健康。
