Project Number: 6408-41000-009-00
Project Type: Appropriated

Start Date: Nov 17, 2009
End Date: Nov 16, 2014

Objective:
1)Discover and develop management strategies for mitigating pre-harvest microbial-derived off-flavors in fish cultured in re-circulating aquaculture systems (RAS) to help reduce off-flavor delayed harvest. 2)Discover and conduct primary development of novel natural and natural-based compounds for controlling disease causing microorganisms in pond-based production systems.

Approach:
Isolate and identify the microorganisms responsible for the most common environmental off-flavors in finfish cultured in recirculating aquaculture systems (RAS). Perform laboratory physiology studies on the off-flavor microorganisms to determine the environmental and nutritional conditions that favor growth and production of the off-flavor compounds. Conduct depuration studies to identify factors such as adipose content of the fish flesh and fish size that may affect depuration rates. Perform efficacy studies to determine if activated carbon filtration can be utilized to reduce levels of the off-flavor compounds in the RAS water and subsequently in fish flesh. Determine the efficacy of antifouling coatings to reduce biofilm formation on RAS culture tank walls and subsequently reduce levels of microbial off-flavor compounds in RAS-cultured fish. Conduct bacterial bioassays to identify natural or natural-product based compounds as potential leads for use in managing diseases in catfish aquaculture. Perform primary development of promising natural compounds identified from bacterial bioassays for use as therapeutic drugs to manage common catfish diseases and improve catfish health.