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


In the shrimp (P. monodon) culture, various diseases, white spot syndrome virus (WSSV) in particular, has become a serious constraint in Bangladesh. Under the study, 72 culture sites from four different locations of Bagerhat (Kochua, Rampal, and Fakirhat) and Khulna (Paikgacha) district were investigated from January to June 2011. Throughout the study period, 20 factors regarding farm management and water quality were keenly considered inferring the association of WSSV outbreak and the farms either claimed infected or not were confirmed by PCR test. Study revealed significant correlation with some factors like accessibility of cattle into the farms (r=0.630, p≤0.01), and farms linked up with surrounding water bodies/farms (r=0.754, p≤0.01) 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≤0.01), followed by temperature (0.624, p≤0.01) and the average depth (-0.618, p≤0.01). However, feeding kept 30.6% farms away from the outbreak followed by sludge removal (26.39% farms). Uses of river water directly into the farms showed 38.9% risk of being attacked which was nil and 1.4% for the underground and rainwater respectively. March to June found to be the disease prone months and out of the four locations, Fakirhat found to be less infected due to better management. Therefore, to cope with the risk of WSSV infection, proper farm management practice, virus free PL (post larvae), awareness buildup at the farmer level and switch into community based farm management can be broadly brought into practice.

Keywords: WSSV; Risk factor; Shrimp (P. monodon); Farm management