Location: Aquatic Animal Health ResearchTitle: Genetic variation in disease resistance traits in hybrid striped bass
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 3/14/2023
Publication Date: N/A
Technical Abstract: White bass (Morone chrysops) and striped bass (Morone saxatilis) are parental species of hybrid striped bass (M. chrysops x M. saxatilis), a fish of increasing commercial importance throughout the US. One chief constraint to the expansion of hybrid striped bass production arises from the use of wild-catch parents in breeding programs. This is costly, unsustainable and leads to uncontrolled variation in the offspring. Our goal is to advance progress in the genetic improvement of hybrids by building additional white bass resources to facilitate selective breeding for agriculturally important traits. White bass were gathered from Arkansas, Texas and Alabama along with available domesticated strains and used to establish a breeding population for familywise evaluations of growth and nutrient utilization on alternative, sustainable diets. In addition to growth and nutritional traits, we are also interested in understanding disease resistance traits and characterizing genetic variation in this trait among moronid fish. Toward this goal, we have established baseline disease susceptibility for several pathogens among white bass, striped bass and their hybrids using our in-house disease challenge system. We are examining the genetic basis of disease resistance using both gene expression data during active infections as well as through genetic mapping of backcross populations. From our studies, we identified differentially expressed genes among species at multiple early time-points post infection with three of the most important bacterial pathogens in moronid aquaculture including Flavobacterium, Aeromonas, and Streptococcus species. Mapping of important gene pathways also revealed unique host-pathogen signature differences among the parental white striped bass and their hybrid. Quantitative trait loci (QTL) data is being investigated.