Genetic parameters of digestive coefficients in three pig breeds
Abstract
Digestive efficiency predicted via near infrared spectrometry (NIRS) is a new indicator of interest for pig selection schemes, making it possible to target a component of feed efficiency particularly interesting in a context where feed contains more dietary fibres. The aim of this study is to estimate genetic parameters of digestive ability for three French pig breeds: Large White, Landrace and Piétrain. Faecal samples at 21 weeks of age were taken from 629 Large White, 188 Landrace and 213 Piétrain male pigs. All Large White animals were genotyped, and digestibility coefficients (DC) for organic matter, energy and nitrogen were predicted from faecal samples by NIRS. Genetic parameters (genetic variance, residual variance and heritability) of DC and genetic correlations with classical production traits (growth rate, feed efficiency and carcass composition) were estimated using REML algorithms considering genotyped data when it was available. Heritabilities of DC estimated were moderate (between 0.10 for DC of nitrogen and 0.35 for DC of energy in Landrace), which is close to estimations reported in the literature for Large White pigs. Heritability for DC in the three breeds were similar, with slightly lower estimates for DC of organic matter in Landrace and Piétrain breeds compared to Large White. Trends of the genetic correlations with production traits were similar in the three breeds: negative for growth rate, feed intake and null for carcass leanness. These first estimates of genetic parameters
for DC in Landrace and Piétrain suggest that the NIRS predictions can be used in most selected pig breeds to further improve feed efficiency.