Association of risk factors: WSSV proliferation in the shrimp farms of south-west coastal region of Bangladesh

In shrimp culture, various diseases, white spot syndrome virus (WSSV) in particular, has been emerging as a serious constraint affecting shrimp culture in Bangladesh. In this study, effort has been given assessing the risk factors for WSSV outbreak under which 72 farms were investigated belonging 4 Upazilas of Bagerhat (Kochua, Rampal, Fakirhat) and Khulna (Paikgacha) district of Bangladesh from January to June 2011. Major scenario depicted improved traditional culture method. PCR test has been carried out to confirm WSSV infection. About 20 factors were considered in assessing the association of WSSV outbreak. Study revealed significant correlation with some factors like accessibility of cattle (r=0.630, p≤.01) and linked up with other ghers (r=0.754, p≤.01) within a cluster (Spearman’s rho correlation coefficient test). Pearson Correlation coefficient for salinity found to have significant correlation with the risk of WSSV infection (r= -0.727, p≤.01), followed by temperature (0.624, p≤.01) and average depth (-0.618, p≤.01), however, feeding kept 30.6% farms away from the outbreak followed by sludge removal (26.39% farms). On the contrary, uses of river water directly into the ghers pose 38.9% risk of being attacked which is absolutely nill and 1.4% for the underground and rain water respectively. Disease prone months found in March to June and out of the four upazilas, Fakirhat found to be less infected due to better management. Therefore, ensuring proper gher management practice, virus free Pl, awareness buildup at the farmer level and community based farm management development can act as preventive measures in reducing the risk of WSSV infection.