Artemia remains a critical feed source for larval fish and crustaceans, underpinning the hatchery production phase for around 10 million tonnes of aquaculture. Yet around 90 percent of current Artemia cysts are wild harvested from salt lakes. There is a need to assure the sustainable supply of Artemia cysts to support hatchery production, from both wild and farmed sources. The International Artemia Aquaculture Consortium has been establihed to explore opportunities in the conservation of Artemia biodiversity, the development of science-based protocols for sustainable harvesting of wild sources, strain selection and selective breeding. NACA will host the consortium.

An online forum will be held on 16 August to enable technical exchange between policymakers, fishery extension officers, researchers and entrepreneurs in development of the freshwater fisheries industry through technology innovation.

The forum will focus on innovations and developments in freshwater fishery biotech, breeding, culture models, digitisation, and industrialisation, featuring presentations and discussions from experts of international organisations, the Chinese Academy of Sciences, Chinese Academy of Engineering, universities and entrepreneurs in virtual exchanges and discussions. Participation is free but registration is required.

With the implementation of the new aquatic animal disease reporting in the Asia Pacific region from January 2021, and in lieu of the published QAAD Reports (last issue published was 4th quarter of 2020), NACA is publishing reported aquatic animal diseases submitted by countries in the Asia-Pacific region.  This report covers the fourth quarter of 2021 and the original and updated reports can be accessed from the QAAD page.

In this issue:

  • NACA to host the International Artemia Aquaculture Consortium
  • Wenzhou virus 8 (WZV8) diagnosis by unique inclusions in shrimp hepatopancreatic E-cells and a molecular detection method
  • Report on the Webinar on Management of Artemia Resources of the Great Salt Lake, 5 May 2022
  • Twentieth Meeting of the Asia Regional Advisory Group on Aquatic Animal Health

In this issue:

  • Ornamental Aquaculture Field School: A new extension approach
  • State of the art of carp spawn production and transportation at Ramsagar, Bankura District, West Bengal, India
  • Seahorse aquaculture: A new paradigm of commercial activity
  • Mixed infections in tropical freshwater fish culture systems: A potential emerging threat for successful aquaculture
  • NACA Newsletter

The aquatic environment contains many opportunistic pathogens and fish are frequently infected by a range of parasites, bacteria, viruses, and fungi. In most incidences of disease, the involvement of two or more pathogens are often seen, which in turn complicates diagnosis and treatment. Here we present a few case studies on mixed infections in aquaculture systems, which may become more common in future due to changing climatic patterns and associated adverse impacts on water quality. Mixed infections seem to be a big challenge to diagnostic laboratories and health specialists in terms of providing a correct diagnosis and treatment.

Seahorses are charismatic livebearers that come under the genus Hippocampus spp. Seahorses are widely distributed in tropical and temperate waters (mostly in the Indo-Pacific region) and different species can tolerate a salinity range of 6-35 ppt.

Seahorses are highly in demand for traditional medicines and curio trade purposes in the dried form and live ones are popular in the marine ornamental aquarium trade. As a result, they are vulnerable to overfishing. Since over-exploitation of these charismatic species has resulted in a drastic reduction in their natural populations, aquaculture of seahorses on a commercial scale may help to reduce pressure on wild stocks. This article provides an overview of seahorse aquaculture in India including research, the production cycle, production systems, and disease issues.

For the last five decades or so, West Bengal has been the leading state in India for the production of production and supply of major carp fry, underpinning the success of freshwater fish culture. This article describes the structure of the hatchery industry in Ramsagar, West Bengal, production practices and systems, packing, transport and links to major seed markets both within the state and elsewhere in India. Market price, broodstock management and natural breeding methods are also discussed.

The Farmer Field School approach is promoted by FAO as an alternative technology dissemination mechanism to the top-down extension methods in south-east Asian countries. In order to utilise the potential of the farmer field school approach for aquaculture, ICAR-CIFA has piloted Aquaculture Field Schools (AFS) in several states in India. AFS are schools without walls to improve the decision-making capacity of the farmers and facilitate cross-learning opportunities. It is a participatory extension methodology whereby fish farmers are allowed to choose the methods of aquaculture production through discovery-based approaches. 

To assist shrimp pathologists worldwide we are providing here photomicrographs of unique basophilic inclusions that are produced by Wenzhou shrimp virus 8 (WZV8),  discovered in 2015 by Li et. al. We designed PCR primers and in situ hybridization probes for detection of WZV8. Subsequent ISH assays with shrimp RT-PCR positive for WZV8 samples indicate unique inclusions described herein as linked to WZV8 in H&E stained tissues. Going back over our previous histological reports and archived slides, we have found the unique WZV8 inclusions in E-cells of normal shrimp samples from several shrimp farming countries in Austral-Asia since at least 2008, and more recently in samples of P. vannamei from the Americas. We urge shrimp pathologists to review their records and specimens for the presence of WZV8 E-cell inclusions described herein to provide data on the global prevalence and impact of WZV8-like infections.