Purple bacteria: A key in the quest to beat 'early mortality syndrome'.

One of the vital sectors in Asia important for social and economic wellbeing is shrimp production. Roughly 49% of the production is intended for local consumption as food source. This segment in the fish industry has a high economic significance as it contributes to an export value of 13 billion dollars in Asia. In 2010 this sector was shuddered by an outbreak of the early mortality syndrome (EMS) or more technically known as acute hepatopancreatic necrosis disease (AHPND). It affects shrimp postlarvae within 20-30 days causing up to 100% mortality. The social and economic effects of EMS/AHPND were (and still are) devastating: losses of USD 1 billion for whole Asian shrimp culture sector, total drop in export of 13% (between 2012-2013) and loss of Thailand's dominant position as the world's leading shrimp exporter. It has been reported that Vibrio parahaemolyticus belonging to the clade the Harveyi is the causative agent of EMS/AHPND. There is an urgent need for a sustainable strategy to prevent new EMS/AHPND outbreaks, respecting besides profit especially the people and the planet. To date, the main controlling strategy is total disinfection of pond sediment and water. It is shown that this approach actually contributes to the epidemic spread of the EMS/AHPND disease rather than controlling it. This is attributed to the action that total disinfection results in a disturbance of the ecosystem and an increase in nutrient availability, favoring fast-growing microorganisms in recolonizing the environment (such as Vibrio spp.). A sustainable alternative for total disinfection can be microbial management strategies. Shrimps are cultivated in ponds along with a microbial community in the water. This stable community is actually a gatekeeper and prevents the growth of pathogenic species. These systems are already proven to decrease Vibrio levels and animal mortality. In this project we look to purple bacteira as a way to prevent EMS. These bacteria can easily grow on side streams of aquaculture cultivation tanks and can be fed as feed ingredient.

Keywords:AQUACULTURE, BIOTECHNOLOGY

Disciplines:Microbiology, Systems biology, Sustainable and environmental engineering, Biomaterials engineering, Biological system engineering, Biomechanical engineering, Other (bio)medical engineering, Environmental engineering and biotechnology, Industrial biotechnology, Other biotechnology, bio-engineering and biosystem engineering, Laboratory medicine, Fisheries sciences