Assessment of hepatic gene expression between hybrid striped bass exhibiting extremes in growth performance

Authors: Abernathy, Jason; Fuller, Adam; Beck, Benjamin; PEATMAN, ERIC - Auburn University; McEntire, Matthew - Matt

Submitted to: Aquaculture America
Publication Type: Abstract Only
Publication Acceptance Date: 11/18/2017
Publication Date: 2/19/2018
Citation: Abernathy, J.W., Fuller, S.A., Beck, B.H., Peatman, E., McEntire, M.E. 2018. Assessment of hepatic gene expression between hybrid striped bass exhibiting extremes in growth performance [abstract]. Aquaculture America, February 19-22, 2018, Las Vegas, Nevada. p. 7.

Interpretive Summary:

Technical Abstract: Hybrid striped bass is a major aquaculture species in the United States. Artificial breeding of this species can introduce large variation in growth performance during grow-out to market size. To assess the genetic and nutrigenomic basis behind growth variability in these hybrids, fingerlings from 47 families were size-matched and communally grown in earthen ponds for 115 days. Afterword, length and weights were taken for all individuals (n=5072) for heritability estimation. Families were then ranked by weight gain and individuals from the three fastest growing (mean 240.8 +/- 9.75 g; 242.0 +/- 11.52 mm) and three slowest growing families (mean 153.5 +/- 52.38 g; 223.3 +/- 21.31 mm) were collected for liver RNA sequencing. As expected, growth characteristics in hybrid striped bass were estimated to be highly heritable (p < 0.0001). Through differential gene expression analysis we identified 86 genes that were responsive between groups including 40 up-regulated (fold-change 1.89 to 7.66) and 46 down-regulated (fold-change -1.71 to -4.59) genes in the largest fish. Two somatic growth-related genes were identified from this list including a growth factor receptor gene and a gene encoding an insulin-like growth factor binding protein that may directly explain some of the genetic variation between families. Several additional genes involved in metabolic pathways such as glycolysis/gluconeogenesis and lipid biosynthesis were also revealed. The candidate gene list may also provide some evidence that both physiological and behavioral factors may be influencing growth differences in communally reared fish. Genetic information revealed through the characterization of growth traits is expected to assist in improvement of breeding practices and selection efforts of the parental white bass and hybrid bass species. Further, understanding these functional characteristics linked to growth variability among bass in common culture systems may help identify solutions to issues affecting more intensive production.