1. Department of Companion Animal and Animal Resources Science, Joongbu University, 1 Daehak-ro, Chubu-myeon, Geumsan-gun, Chungnam 312–702 South Korea
2. College of Veterinary Medicine and Research Institute for Veterinary Science, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151–742 South Korea
3. Department of Statistics, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 151–742 South Korea