Protein phenotypes and productive traits in Landrace, Large White and Duroc swine

Abstract

Fourteen protein systems coded by 15 structural loci were typed by horizontal electrophoresis to determine possible associations betweem the protein phenotypes and productive traits in Landrace (N=109), Largo White (N= 116) and Duroe (N=57) pigs, reared in Southern Brazil. Signiticant associations between protein phenotypes and production traits were detected. The most consistent interaction were observed between two protein systems (phosphogluconate dehydrogenase - Pgd and Hemopexin -Hpx) and at least one of the four performance variables considered. In Duroc breed, the Pgd phenotypes were associated with daily weight gain (P < 0.01), feed conversion ratio (P < 0.01) and selection index (P < 0.001), while in Landrace significant associations were observed only with feed convertion ratio (P < 0.05). The Hpx phenotypes were associated with daily weight gain (P < 0.05) and backfat thickness (P < 0.05) in Large White and with this last variable (P < 0.01) and selection index (P < 0.05) in Duroc pigs. Since these results had not been reported previously, turther studies are need to confirm these associations.