|Leeds, Timothy - Tim|
|Wiens, Gregory - Greg|
|LAPATRA, SCOTT - Clear Springs Foods, Inc|
Submitted to: International Aquatic Animal Health Symposium Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 6/15/2014
Publication Date: 9/1/2014
Citation: Evenhuis, J., Leeds, T.D., Wiens, G.D., Lapatra, S.E. 2014. Evaluating innate resistance to Flavobacterium Columnare in rainbow trout (Oncorhynchus mykiss)[abstract]. International Aquatic Animal Health Symposium Proceedings. Paper No. 9C.
Technical Abstract: Flavobacterium columnare (Fc) is the causative agent for columnaris disease and a problem for several fish species. Recently, columnaris has been recognized as an emerging problem in farmed trout cultured within the Hagerman valley of Idaho. A long term breeding program at the NCCCWA has produced several genetic lines of rainbow trout that have divergent resistance to an F.pychrophilum (Fp) intraperitoneal injection challenge. The resistance of these lines to challenge with Fc has not been previously investigated. Several families from 2 different lines were tested for innate Fc resistance: ARS-Fp-R (resistant) and ARS-Fp-S (susceptible). Overall, survival between families ranged from 87% down to 3%; within family variation was 87% to 18% for ARS-Fp-R and 73% to 3% for ARS-Fp-S families. The average survival for the ARS-Fp-R and ARS-Fp-S families was 56% and 38%, respectively. Genetic correlation between innate resistance for Fp and Fc was determined, using the linear MTDFREML modeling system, to be 0.40. Heritability of innate resistance to Fc was determined to be 0.17, which was exactly the same determined for innate Fp resistance for this population of trout. The genetic correlation between innate Fc resistance and 9-month body weight was calculated at -0.09. In summary, within line family variation for innate Fc resistance can vary up to 84% and on average the ARS-Fp-R line of trout performed better than the ARS-Fp-S line. The low calculated heritability for innate Fc resistance suggests that breeding for improved innate resistance to Fc can be accomplished with a focused breeding protocol.