COMPARISON ON BACTERIAL LOAD Vibrio OF SELECTED CREEKS FOR SHRIMP FARMING IN TAMIL NADU

Penaeus vannamei is one of the most farmed shrimp species globally. Disease caused by viral and bacterial agents is one of the major impeding factors for profitable shrimp aquaculture. Vibrio infection is a continuous problem in Penaeus vannamei culture throughout the world. The current study estimates the presumptive Vibrio count to assess the status of water quality in major creeks of Nagapattinam, Thiruvarur, Thanjavur and Pudukottai districts in relation to their potential for shrimp aquaculture use. The study was conducted for a period of six months from October 2017 to March 2018. For the microbiological study, the samples were collected from the creeks at 10 days interval and stored at 4^oC. The collected samples were analyzed using standard procedures. Presumptive Vibrios was made on Thiosulphate citrate bile salts sucrose (TCBS) agar medium from both water and soil. The total Vibrio count is expressed as colony forming unit per ml (CFU ml^-1). In the microbial analysis the bacterial colonies ranged from 1.0×10^-1 to 4.6×10^-3 CFU/ml (Water sample) and 1.0 ×10^-1 to 8.0×10^-2 (Soil sample) showed in Table.1. For the water sample, the highest microbial count was observed in Senthalaipattinam and the lowest range was observed in Sembodai. A highest microbial count was observed in Chinnathambur and the lowest range was observed in Vadakadu of a soil sample.