Detection of Colistin Sulfate on Piglet Gastrointestinal Tract Microbiome Alterations

SIMPLE SUMMARY: The gut microbiome plays important roles in maintaining host health. Overuse of antibiotics could cause microbial resistance and host intestinal flora dysfunction, contributing to serious disease. Colistin is widely used as a feed additive to enhance swine growth and the phenomenon of colistin resistance has been widely reported. Therefore, in this study we wanted to evaluate the effect of colistin on the gastrointestinal tract microbiome composition in piglets. Our results demonstrated that colistin could change the gastrointestinal tract microbiome composition of piglets, which provides us with a new strategy for rational utilization of colistin to protect animal and human health. ABSTRACT: The gut microbiome exerts important functions on host health maintenance, whereas excessive antibiotic use may cause gut flora dysfunction resulting in serious disease and dysbiosis. Colistin is a broad-spectrum antibiotic with serious resistance phenomena. However, it is unclear whether colistin alters the gastrointestinal tract microbiome in piglets. In this study, 16s rDNA-based metagenome analyses were used to assess the effects of colistin on the modification of the piglet microbiome in the stomach, duodenum, jejunum, cecum, and feces. Both α- and β-diversity indices showed that colistin modified microbiome composition in these gastrointestinal areas. In addition, colistin influenced microbiome composition at the phylum and genus levels. At the species level, colistin upregulated Mycoplasma hyorhinis, Chlamydia trachomatis, Lactobacillus agilis, Weissella paramesenteroides, and Lactobacillus salivarius abundance, but downregulated Actinobacillus indolicus, Campylobacter fetus, Glaesserella parasuis, Moraxella pluranimalium, Veillonella caviae, Neisseria dentiae, and Prevotella disiens abundance in stomachs. Colistin-fed piglets showed an increased abundance of Lactobacillus mucosae, Megasphaera elsdenii DSM 20460, Fibrobacter intestinalis, and Unidentified rumen bacterium 12-7, but Megamonas funiformis, Uncultured Enterobacteriaceae bacterium, Actinobacillus porcinus, Uncultured Bacteroidales bacterium, and Uncultured Clostridiaceae bacterium abundance was decreased in the cecum. In feces, colistin promoted Mucispirillum schaedleri, Treponema berlinense, Veillonella magna, Veillonella caviae, and Actinobacillus porcinus abundance when compared with controls. Taken together, colistin modified the microbiome composition of gastrointestinal areas in piglets. This study provides new clinical rationalization strategies for colistin on the maintenance of animal gut balance and human public health.