Asia: Research – Review of Shrimp Diseases
Abstract: This review summarizes recent information about new and newly emerging diseases of cultured shrimp in Asia and discusses the biosecurity lapses that led to the current shrimp production crisis. All industry stakeholders must be aware of this situation and of the need for regional and global collaborative efforts to stem this crisis and prevent future development of another.
In Asia, several shrimp diseases are new or newly emerged, including acute hepatopancreatic necrosis disease (AHPND), hepatopancreatic microsporidiosis (HPM), hepatopancreatic haplosporidiosis (HPH), aggregated transformed microvilli (ATM) and covert mortality disease (CMD).
In addition to these, whitespot disease (WSD), yellowhead disease (YHD) and infectious myonecrosis (IMN) continue as the most serious viral threats to shrimp farmers in the region.
Other diseases such as Penaeus monodon slow growth syndrome (MSGS), white tail disease (WTD) and abdominal segment deformity disease (ASDD) are of less concern. In contrast, Taura syndrome virus (TSV) and infectious hypodermal and hematopoietic necrosis virus (IHHNV) have become innocuous due to the widespread use of the highly tolerant specific pathogen free (SPF) stocks of Penaeus (Litopenaeus) vannamei that dominate production. Similarly, diseases caused by monodon baculovirus (MBV) and hepatopancreatic parvovirus (HPV) appear not to affect P. vannamei.
The spread of diseases has been promoted by the use of live or fresh broodstock feeds such as polychaetes and clams. Also, shortages of imported SPF broodstock led some entrepreneurs to use postlarvae (PL) of imported SPF stocks to produce second-generation broodstock in open shrimp ponds. They became contaminated and were then used to produce PLs for stocking ponds. These practices left the whole shrimp industry vulnerable to the rapid spread of the new and newly emerging diseases and resulted in the current crisis in Asian shrimp culture. The situation has been exacerbated since 2009 by an almost exclusive focus on AHPND, which is only partially responsible for what has been widely called early mortality syndrome (EMS).
The purpose of this review is to summarize progress of research on AHPND bacteria and also to encourage a wider focus on additional pathogens that are causing farm losses. The significance of these diseases and their implications for the future of shrimp aquaculture are discussed.
Source: Aquaculture. Review of Current Disease Threats for Cultivated Penaeid Shrimp in Asia. Siripong Thitamadee, Anuphap Prachumwat, Jiraporn Srisala, Pattana Jaroenlak, Paul Vinu Salachan Kallaya Sritunyalucksana, Timothy W. Flegel and Ornchuma Itsathitphaisarn (email firstname.lastname@example.org, Center of Excellence for Shrimp Molecular Biology and Biotechnology, Faculty of Science, Mahidol University, Rama VI Road, Bangkok 10400, Thailand). Scheduled for publication in the February 16, 2016, issue of Aquaculture (Volume 452, Pages 69–87).