Genetic selection is a cost-effective and complementary strategy to traditional methods of improving animal health and welfare. Nonetheless, efforts to incorporate animal health and welfare traits into international breeding programmes have been hindered by the availability of informative phenotypes.
The recent Bovine Viral Diarrhea (BVD) eradication programme in the Republic of Ireland provides an opportunity to quantify the potential benefits that genetic selection can bring to other BVD eradication programmes and to provide information on possible eradication programmes for other diseases in the Republic of Ireland.
Using a dataset of 188,085 Irish calves, estimates of direct and maternal heritability at birth of calves with persistent infection following possible exposure to BVD virus in utero ranged from zero (linear model) to 0, 29 (SE = 0.075; threshold model) ) and ranged from essentially zero (linear model) to 0.04 (SE = 0.033; threshold model), respectively.
The corresponding genetic SDs for direct and maternal effects for binary traits (0, 1) ranged from 0.005 (linear model) to 0.56 (threshold model) units and 0.00008 (linear model) to 0.20 (threshold model) units, respectively. The coefficient of direct genetic variation based on the linear model was 2.56%, indicating that considerable genetic variation can be exploited.