Green water technology is a technique that promotes phytoplankton to grow profusely, and includes several methods by which desirable microalgae are produced for the purpose of rearing larval fish and crustaceans. Naturally occurring phytoplankton, which serve as feed for fish and crustacean larvae, are grown and proliferate under a controlled system. This article describes the use of greenwater and co-feeding techniques in the rearing of hilsa, Tenualosa ilisha, principally making use of Chlorella and rotifers.

Development of small-scale aquaculture has dominated development discourse because of its potential to fight malnutrition and poverty, to ensure food security and enhance the socio-economic condition of people living at the bottom of the pyramid. Aquaculture has contributed to strengthening livelihoods and food security in southeast Asian countries, contributing to the livelihood of the poor farmers through improved food supply, income and employment.

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 4^th 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:

• 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.

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. 

The Fish Health Section of the Asian Fisheries Society is inviting you to a Zoom Webinar on Viral Diseases of Aquatic Animals, 1 June at 13:00 Bangkok time (GMT +7).

Participation is free but advance 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 4^th 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.