Heritability of sow longevity and lifetime prolificacy in Finnish Yorkshire and Landrace pigs
The objective of this study was to estimate genetic parameters for longevity traits in Finnish pig populations. Analyzed traits were length of productive herd life (LPL), total number of parities (TNP), total number of piglets born (TNB), total number born alive (TBA) and stillborn (TSB), percentage stillborn (SB%), total number of piglets dead before weaning (TPM), mortality percentage (PM%), and total number weaned (TNW). Data contained litter records from 29 805 Finnish Landrace and 25 807 Finnish Yorkshire sows. Variance components were estimated using the AI-REML method. Heritability estimates varied from 0.06 to 0.11 in Finnish Landrace and from 0.09 to 0.12 in Finnish Yorkshire. Genetic correlations were high (> 0.9) between LPL, TNP, TNB, TBA, and TNW, and low between piglet mortality traits (SB% and PM%) and other longevity traits. The obtained heritability estimates indicate that there is sufficient genetic variation for selection.