Enhanced bacterial disease resistance of transgenic channel catfish Ictalurus punctatus possessing cecropin genes

The cecropin B gene from the moth Hyalophora cecropia, driven by the cytomegalovirus promoter, was transferred to the channel catfish Ictalurus punctatus. Transgenic individuals (PI) were mated to produce individuals (F-1) that exhibited enhanced disease resistance and survival when challenged with pathogenic bacteria, During the epizootic of Flavobacterium columnare in an earthen pond, the percentage of transgenic individuals containing preprocecropin B construct that survived (100%) was significantly, greater (P < 0.005) than that of nontransgenic controls (27.3%). Also, when challenged in tanks with Edwardsiella ictaluri, the causative agent of enteric septicemia of catfish, the percentage of transgenic individuals containing catfish 19 leader cecropin B construct that survived (40.7%) was significantly greater (P < 0.01) than that of nontransgenic controls (14.8%). There were no pleiotropic effects of the transgenes, and growth rates of the transgenic and nontransgenic siblings were not different (P > 0.05). Inheritance of the transgene by the F-1 generation, 20.2% to 30.7% was typical of that in studies with transgenic channel catfish.