TÓM TẮT NỘI DUNG:

A new emerging disease in shrimp, first reported in 2009, was initially named as Early Mortality Syndrome (EMS).   In 2011, a more descriptive name for the acute phase of the disease was proposed as Acute Hepatopancreatic Necrosis Syndrome (AHPNS). The disease is significant in Southeast Asian shrimp farms of both Pacific white shrimp (Penaeus vannamei) and black tiger shrimp (Penaeus monodon), usually occurring within the first 45 days after stocking and is causing significant losses to the shrimp farming industry of the region. The disease was first classified as an idiopathic disease because no specific causative agent was identified. In an attempt to determine the infectious nature of this disease, the Aquacutlure Pathology Laboratory at the University of Arizona has conducted several on-site infectivity studies in an EMS/AHPNS endemic area in Vietnam. In those studies, only fresh and live infected tissues were used in inoculums preparation. Those infectivity studies included: intramuscular injection with filtered and unfiltered inoculums, per os, reverse gavage with unfiltered inoculums, and cohabitation. The histological analyses indicated that the per os and cohabitation studies could introduce pathology that consistently appears in EMS/AHPNS infected animals.