Diversidade de Vibrio spp. em estuários no Estado do Ceará associada à atividade de carcinicultura

Abstract

An economically attractive investment, marine shrimp farming is on the rise not only in Brazil but also all over the world. Farms in Northeastern Brazil account for most of the country’s shrimp production. However, shrimp populations have been constantly submitted to bacterial infections caused by vibrios endemic to estuarine and freshwater environments. These bacteria are associated with the shrimp microbiota during the early larval stages and may be isolated from both healthy animals and the environment itself. The present study consists of a survey of the species diversity of genus Vibrio occurring in four mangrove areas located on the Choró, Pirangi, Jaguaribe and Pacoti rivers’ estuaries, in Ceará State, three of which with shrimp farms and one without (control). Water and sediment samples were taken inside the four estuaries as well as in the inflow and outflow channels and ponds of a Litopenaeus vannamei shrimp farm. As a results of this research work, 138 strains of Vibrio were isolated and identified from estuarine water and sediment samples and 25 from samples collected on the farm. The Vibrio species most frequently observed were V. logei, V. parahaemolyticus, V. fluvialis and V. cholerae (in samples from the environment) and V. logei and V. cholerae (in samples from the farm). Our findings suggest that, since vibrios were found in estuaries both with and without shrimp farming activities and the species diversity was greater in the environment than on the shrimp farm, estuaries are not negatively impacted by shrimp culture as far as the genus Vibrio is concerned.