Identification of bacteria causing Vibriosis (Vibrio sp) on white snapper (Lates calcarifer) reared in the marine cultivation ponds

Abstract

Vibrio is a group of bacteria that causes Vibriosis in many aquatic biota cultivated in ponds. This research aims to determine the type of the Vibrio sp. which causes vibriosis disease in white snapper reared in the marine cultivation ponds at the Center for Marine Cultivation Fisheries (CMCF) Lampung, Indonesia. The research was conducted using investigative method by isolating Vibrio bacteria from the organ in white snapper, mud, and water. The bacterial isolates were indentified using biochemical test. The reseach parameters are TPC (Total Plate Count) Vibrio sp., water temperature, pH, salinity, DO, BOD and ammonia. The results showed there were three types of isolates that are suspected as the Vibriosis bacteria in white snapper fish namely Vibrio vulnificus, Vibrio alginolyticus and Vibrio parahaemolyticus. The three isolates obtained were known to be α-hemolysis. The enviromental quality parameters are as follows: water temperature of 29.8 °C, pH 7.8, salinity 33 psu, DO 4.4 mg / L, BOD 2.2 mg / L and ammonia 2.2 mg / L. The TPC-values of the bacteria Vibrio sp. isolated from the inlet, the main chambers, and the outlet of the pond are: <25 CFU/ ml, 7.6x104 CFU/ml, and 2.1x103 CFU/ml respectively. The levels of ammonia and calculation of TPC-values of Vibrio bacteria are exceeds the water quality standards for the fish farming.