[1] Univ Guelph, Dept Populat Med, Ontario Vet Coll, Epidemiol, 50 Stone Rd East, Guelph, ON N1G 2W1, Canada
[2] Univ Guelph, Ontario Vet Coll, Dept Populat Med, 45 McGilvray St, Guelph, ON N1G 2W1, Canada
[3] Univ Guelph, Hills Pet Nutr Primary Healthcare Ctr, 45 McGilvray St, Guelph, ON N1G 2W1, Canada
[4] Univ Guelph, Ontario Vet Coll, Dept Populat Med, 50 Stone Rd East, Guelph, ON N1G 2W1, Canada
[5] Univ Guelph, Ontario Vet Coll, Dept Clin Studies, Small Anim Med, 50 Stone Rd East, Guelph, ON N1G 2W1, Canada