The composition and natural variation of the skin microbiota in healthy Australian cattle

Abstract

Abstract Background Skin diseases in cattle pose significant animal welfare issues and financial burdens. Microbial communities inhabiting the skin have essential roles in maintaining host health. Microbiota manipulation can be an efficient strategy for improving the productivity and sustainability of skin disease management. However, a lack of information on the skin microbiota of healthy cattle and how environmental and host factors drive its normal variation has limited using skin microbes for diagnosing or treating skin disease and pest infestation in cattle. Here, we profiled the skin microbiota of 1,734 healthy cattle from 25 different herds located in a 187,000 km2 area in the northeast to east Australia using 16S rRNA gene amplicon sequencing. The impact of host and climatic conditions on the skin microbial populations was examined. Results Our results demonstrate a highly diverse microbiota on the skin of healthy cattle. While the structure and diversity of microbial communities varied between herds, several bacteria were present consistently despite the differences in environmental conditions. For example, bacterial families Moraxellaceae, Sphingomonadaceae, Bacillaceae and Burkholderiaceae were observed in most cattle, however, their relative abundance varied significantly between herds. Solar exposure and rainfall were key factors contributing to the observed variations in skin microbiota between herds, while temperature and cattle breed did not show any statistically significant impact on the composition of cattle skin microbiota. Conclusions This is the first report of the composition of the commensal skin microbiota of healthy cattle, specifically herds located in the northeast to east Australia and the impact of environmental and host variables on these microbial communities. Our study provides valuable insight into normal variation in cattle skin microbiota, an essential step for developing skin microbiota-based therapies for skin disease present in cattle.