Location: Natural Products Utilization Research
2017 Annual Report
Objectives
1. Develop management strategies to mitigate pre-harvest microbial-derived off-flavors in fish cultured in recirculating aquaculture systems (RAS) to reduce off-flavor delayed harvest.
2. Discover and develop management strategies to mitigate pre-harvest microbial-derived off-flavors in fish cultured in outdoor earthen ponds to reduce off-flavor delayed harvest.
2.A. Evaluate and identify the impact of split-pond production practices in reducing or enhancing the incidences and intensities of common pre-harvest off-flavors in channel catfish.
2.B. Further evaluation of biofloc technology (BFT) production systems for the benefits in managing common pre-harvest off-flavors in cultured finfish.
2.C. Evaluation of a biocontrol approach in reducing the abundance of common off-flavor producing cyanobacteria in catfish production ponds.
Approach
Develop management strategies to mitigate pre-harvest microbial-derived off-flavors in fish cultured in recirculating aquaculture systems (RAS) to reduce off-flavor delayed harvest. Discover and develop management strategies to mitigate pre-harvest microbial-derived off-flavors in fish cultured in outdoor earthen ponds to reduce off-flavor delayed harvest. Evaluate and identify the impact of split-pond production practices in reducing or enhancing the incidences and intensities of common pre-harvest off-flavors in channel catfish. Further evaluation of biofloc technology (BFT) production systems for the benefits in managing common pre-harvest off-flavors in cultured finfish. Evaluation of a biocontrol approach in reducing the abundance of common off-flavor producing cyanobacteria in catfish production ponds.
Progress Report
A relatively new design of outdoor, earthern aquaculture ponds referred to as partitioned aquaculture systems (PAS) or split-ponds is growing in acceptance and use by aquaculturists for the production of channel catfish in the southeastern United States. However, no previous research on the composition of phytoplankton communities and the occurrence and intensities of common off-flavors in catfish such as “earthy” and “musty” within split-ponds has been performed. Analysis of collected water samples during both years of a two-year study have determined that the occurrences and intensities of earthy and musty off-flavor problems in split-pond systems are very similar to those that can occur in conventional catfish ponds (non-partitioned) which producers have utilized in the past. Therefore, catfish farmers can utilize similar management practices for pond water quality (e.g., dissolved oxygen) and for undesirable species of cyanobacteria (blue-green algae) in split-ponds as to those used for conventional ponds.
Accomplishments
Review Publications
Schrader, K., Cantrell, C.L., Midiwo, J.O., Muhammad, I. 2016. Compounds from Terminalli brownii extracts with toxicity against the fish pathogenic bacterium Flavobacterium columnare. Natural Product Communications. 11(11):1679-1682.
Schrader, K., Harries, M.D., Page, P. 2016. Effects of pH on biomass, geosmin, and 2-methylisoborneol production and cellular activity by Streptomyces luridiscabiei isolated from a rainbow trout recirculating aquaculture system. Annals of Aquaculture and Research. 3(3):1027.
Schrader, K., Tucker, C.S., Brown, T.W., Torrans, E.L., Whitis, G.N. 2016. Comparison of phytoplankton communities in catfish split-pond aquaculture systems with conventional ponds. North American Journal of Aquaculture. 78:384-395.
