2B-105: Genetic Parameters for Health, Survival, Immune Competence, Post-Weaning Growth and Disease Resilience of Pigs

Abstract

Immune and haematological traits had moderate to high heritabilities. Further, multiple immune and haematological traits had significant genetic correlations with growth traits. Average growth of a group of pigs was lower for groups of pigs that required more medication. This finding confirms the concept of growth as a health indicator. A simple score about whether a pig was medicated or not was lowly heritable in this high-health herd which offers new opportunities for genetic improvement of health of pigs. The heritability was not significantly affected by the approach to account for non-medicated pigs which provides extra flexibility for the definition of this trait for genetic evaluations. Medication of pigs has economic and welfare costs. The economic value of medication score is based on the cost of medication and loss in productivity due to the disease incidence. Disease resilience is a two-dimensional trait which requires definition of environmental challenges. In this regard, it is important to separate other environmental, non-infection stressors from infection challenges. Methodology was developed to obtain finer descriptions of possible infection challenges by removing climatic effects from environmental descriptors using performance data recorded on farms. An on-farm measure of haemoglobin was genetically the same trait as haemoglobin measured in the laboratory. However, the on-farm measure of haemoglobin had a lower heritability than the laboratory measure due to larger residual variation which indicates measurement errors for the on-farm measure.