Vibrio spp. em hemolinfa de camarões Litopenaeus vannamei coletados em três fazendas de cultivo do estado do Ceará

Abstract

The purpose of the present study is to relate coagulation time with Vibrio presence in the haemolymph of shrimps reared in three farms located in Ceará State, sampled during the dry season and the rainy season from October 2005 to October 2006. In all, 18 samples were withdrawn, in each of which 10 shrimps were analyzed. The cultivation time of the experiment varied from 60 to 120 days. Clotting ability of shrimp haemolymph colected in the farms and in both periods varied in the range of 5 - 55 seconds, in 51 shrimps infected with Vibrio and, for the remaining ones (129) not infected, the intermission time ranged from 4 to 57 seconds. The Standard Plate Count (SPC) of Vibrio in haemolymph of the infected individuals varied from 10 to 28.000 Colony Forming Units (CFU/mL). For the farms A, B and C the intervening times of Vibrio SPC in haemolymph in the dry period were, respectively 1,000; from 10 to 140, and from 1.000 to 28.000; for the rainy period, they varied from 10 to 2,000, from 110 to 1,000 and from 10 to 1,605 CFU/mL. Out of 132 isolated strains of the shrimp haemolymph which contained Vibrio, 13 species were identifi ed. The highest diversity of Vibrio was observed in the following decreasing order of the farms, namely B, C and A, and also that haemolymph contamination was mostly favoured by rainfall. No relationship was found between bacterian presence in the haemolymph and coagulation time