BACTERIAL MICROBIOTA FROM WILD FRESHWATER FISH UTILIZED FOR SUBSISTENCE IN WESTERN MEXICO

Abstract

Microbiological analyses of freshwater fish utilized in subsistence fisheries are relatively scarce. These fisheries are widespread throughout Latin America, and support numerous communities in rural, impoverished areas. We present the results of genetically-based microbiological analyses of river water samples and fish tissue samples obtained from specimens (n = 128) captured in the wild from three sites in the Ayuquila river, west central Mexico. The system is affected by numerous human activities. We identify 11 bacterial taxa of which Pseudomonas stutzeri , Shigella sonnei, Escherichia coli and Bacillus subtilis were isolated from the most fish. Citrobacter freundii and E. coli were present in water samples from all sites. Average taxa richness was similar among rainy and dry seasons. Enterobacteriaceae dominate the bacterial microbiota of water and fishes of the Ayuquila river, suggesting there is significant influence from anthropic activities in the basin. Our findings provide a baseline upon which to improve our understanding of the microbiology of the Ayuquila river and similar systems in west central Mexico, especially related to risks for biota and human populations dependent on rivers for sustenance.