TÓM TẮT NỘI DUNG:

White spot disease (WSD) which caused by white spot syndrome virus (WSSV) is the most serious epidemic in black tiger shrimp (Penaeus monodon) and brings to farmers severe damages annually. The study is implemented from September 2010 to September 2011 to identify risk factors occured with white spot disease (WSD) in black tiger shrimp (Penaeus monodon) extensive culture in Cai Nuoc district, Ca Mau province. The monthly average rate of WSD in the investigated area was 26.3%. The survey was conducted by interviewing 480 shrimp farms with structured questionnaires before a logistic model regression with 38 variables regarding to pond condition, seeding, feeding, pond management, yield and WSD occurance. The statistical results showed that water exchange, environmental testing pond, wild shrimp, disease in the neibouring ponds, wide ditch, yields and harvesting size are significantly associated with WSD occurrance in shrimp ponds. The logistic regression predicted that in good conditions, the probability of WSD occurrance is 7,41%. In bad conditions, the probability is estimated to be 95,11%. The findings from this study are expected to contribute scientific literature for further studies in order to establish technical procedures appropriate to improved-extensive shrimp farming systems in Ca Mau province and nearby areas.