Genetic Correlations among Average Daily Gain, Backfat Thickness and Sow Longevity in Landrace and Yorkshire Sows

Abstract

The present study aimed to estimate heritabilities as well as genetic correlations of sow longevity with average daily gain and backfat thickness. Removed sows included in the current study were 1,706 Landrace sows and 1,159 Yorkshire sows. They were raised in a Thai swine breeding herd and removed in the 2008-2013 period. Sow longevity was defined as the number of days from first farrowing date to removal date. Genetic parameters were estimated by using the Restricted Maximum Likelihood (REML) method with a multiple-trait animal model. On average, the sow longevity, average daily gain and backfat thickness were 633 days, 863 g/day and 11.8 mm, respectively, for the Landrace sows and were 579 days, 805 g/day and 10.7 mm, respectively, for the Yorkshire sows. Heritability estimates for sow longevity, average daily gain and backfat thickness were, respectively, 0.15, 0.31 and 0.57 for the Landrace sows; 0.11, 0.23 and 0.46 for the Yorkshire sows. The sow longevity was found to be unfavorably genetically correlated with the average daily gain and backfat thickness in both Landrace sows (-0.27 and 0.24) and Yorkshire sows (-0.36 and 0.30). Selection for average daily gain and backfat thickness may result in shorter sow longevity. The heritability estimates obtained also indicated that selection for sow longevity would be possible. In spite of the existence of unfavorable associations, it should be pointed out that the relationships are not extremely high, suggesting that selection for these traits simultaneously is likely achievable.