1. Department of Biomedical Sciences, Ontario Veterinary College, University of Guelph, Guelph ON, N1G 2W1 Canada
2. Department of Animal Science, McGill University, Ste-Anne-de-Bellevue QC, H9X 3V9 Canada
3. Department of Swine and Small Ruminant Breeding, University of Agriculture in Kraków, 30-274 Kraków, Poland