Ocorrência de enterobactérias em Colossoma macropomum (CUVIER, 1816) criados em sistema intensivo na Ilha do Maranhão: impacto para a sanidade animal e saúde pública?

Abstract

Colossoma macropomum (tambaqui) is a species native to the Brazilian Amazon that has good zootechnical performance in intensive farming, constituting the basis of fish farming in Maranhão. However, for good aquaculture production, there is a need to disseminate good nutritional, reproductive and sanitary management practices, the latter including periodic monitoring of the presence of pathogens in water and fish. In this context, the objective of this study was to evaluate the occurrence of enterobacteria in C. macropomum farmed in an intensive production system on Maranhão Island. For this purpose, 40 tambaquis, including males and females, from 10 fish farms on Maranhão Island were captured. In a laboratory environment, muscle fragments were removed from the samples for quantification of total and thermotolerant coliforms, isolation and bacterial identification. The phenotypic identification of enterobacteria was performed using a commercial biochemical panel composed of 23 parameters. Total coliforms and thermotolerant coliforms were quantified in 30% (n = 12/40) and 15% (n = 6/40) of the fish evaluated, respectively, with bacterial populations ranging from 3.6 to ≥ 2,400 MPN/g. Of the 12 samples of C. macropomum contaminated by bacteria from the coliform group, 63 isolates were obtained with the identification of eight distinct species of enterobacteria, distributed as follows: Proteus vulgaris (28.57%); Citrobacter freundii (19.05%); Proteus mirabilis (14.29%); and Escherichia coli (14.29%). Kluyvera ascorbata, Providencia alcalifaciens, Edwardsiella hoshinae and Escherichia hermannii were also identified, but at lower frequencies. It is concluded that the eight species of enterobacteria isolated are indicative of inadequate hygienic-sanitary conditions and represent epidemiological and sanitary risks for the environment, aquatic biodiversity and human health