Start Date: Dec 14, 2004
End Date: Dec 13, 2009
To attain the first objective, we will measure growth and carcass yield in catfish after rearing in ponds; correlate levels of growth hormone, insulin-like growth factors I and II (IGF-I, IGF-II)and IGF binding proteins (IGFBPs) with growth efficiency in catfish families; quantify family variation in resistance to E. ictaluri in the 5th and 6th generations of the USDA103 line; and determine levels of gonadotropic hormones in spawning catfish and correlate with individual variation in reproductive efficiency. For the second objective, we will add interspecific conserved genes to the catfish genetic linkage map to facilitate comparative genomic analyses; identify chromosomal regions (quantitative trait loci) containing genes controlling carcass yield and resistance to ESC; develop molecular markers for disease resistance candidate genes based on comparative functionality with other species; and identify candidate genes and gene products controlling economically important traits using differential gene expression on oligonucleotide microarrays. For the third objective, we will develop and implement an index based on breeding values of traits and their economic values to select individuals with superior composite phenotypes; and quantify differences in performance for production traits between selected lines and the USDA103 base population.