PSIII-13 Genetic parameters and the purebred–crossbred genetic correlation for growth, carcass, and meat quality traits in pigs

Abstract

Abstract Growth, meat quality, and carcass traits are of economic importance in swine breeding. Understanding their genetic basis in commercial crossbred pigs and purebred-crossbred genetic correlations are necessary for a successful breeding program. The objectives of this study were to 1) estimate genetic parameters for growth, meat quality and carcass traits in a purebred sire line and related commercial crossbred pigs and 2) estimate the corresponding genetic correlations between purebreds and crossbreds (rpc). We analyzed 115266, 10927 and 43057 purebred records for growth, meat quality (n = 4) and carcass traits (n = 7), respectively. For crossbreds, there were 2000 pigs with growth records, with 900 of them having meat quality and carcass data. A series of univariate and bivariate analyses were used to estimate genetic parameters and rpc. Growth showed moderate heritability (0.20 ± 0.10 to 0.25 ± 0.01) in both purebreds and crossbreds. Heritability estimates for meat quality traits ranged from 0.21 ± 0.03 to 0.42 ± 0.04 in purebreds and from 0.17 ± 0.14 to 0.47 ± 0.15 in crossbreds. Carcass traits had higher heritability estimates in purebreds compared to crossbreds, except for hot carcass weight (0.10 ± 0.02 vs. 0.24 ± 0.16). Genetic correlations among meat quality traits were variable in both populations, whereas genetic correlations among carcass traits were similar in purebreds and crossbreds. Estimates of rpc were high for growth (0.99 ± 0.5) and for meat quality traits (0.94 ± 0.39 to 0.99 ± 0.2), except for Minolta color (-0.48 ± 0.56). Carcass traits had moderate to high estimates of rpc (0.64 ± 0.4 to 0.92 ± 0.3). Carcass fat had a negative estimate of rpc (-0.1 ± 0.5). However, ultrasound fat as an indicator trait for carcass fat had a high positive estimate of rpc (0.88 ± 0.14). Our results indicate that selection in purebreds can be efficient to improve these traits in both purebreds and crossbreds but for some traits, genetic gain can be improved by applying combined crossbred and purebred selection. Funding provided by Genome Canada and the National Research Council.