Presence of multiple viruses in non-diseased, cultivated shrimp at harvest

摘要: Abstract Histological examinations were carried out with 400 cultivated black tiger shrimp ( Penaeus monodon ) from 12 commercial rearing ponds three different areas in Thailand over a period of 3 years. The collected at or near harvest time as two arbitrary size groups 10–20 each pond. Aside difference, they showed no gross signs disease and normally active. Pathognomonic histopathological lesions found only for hepatopancreatic parvovirus (HPV) baculovirus (MBV). Although these relatively frequent, unusual mortality had occurred any the examined. Severity infections was negatively correlated size. When grouped together, HPV-infected gave mean lengths approximately 6.5 cm that significantly uninfected 9 length, early cultivation cycle while MBV-infected length not readily distinguishable until 10 more, later cultivation. Thus, HPV infection more severe stunting than MBV. In addition to examination, polymerase chain reaction (PCR) assays HPV, white spot syndrome virus (WSSV) infectious hypodermal hematopoietic necrosis (IHHNV) on one large sample 240 6 where visible apparent MBV only. Surprisingly, 94% specimens positive test least four viruses. IHHNV alone combination detected high prevalence (approximately 60%) despite absence histological confirmed by southern blot hybridization. viral pathogens very high, it would have gone unnoticed, since normal are rarely examined