[1] Hokkaido Univ, Grad Sch Vet Med, Dept Vet Clin Sci, Lab Vet Internal Med, N18 W9, Sapporo, Hokkaido 0600818, Japan
[2] Texas A&M Univ, Dept Small Anim Clin Sci, Gastrointestinal Lab, College Stn, TX 77843 USA
[3] Hokkaido Univ, Grad Sch Vet Med, Vet Teaching Hosp, Sapporo, Hokkaido, Japan
[4] Univ Tokyo, Grad Sch Agr & Life Sci, Dept Vet Internal Med, Tokyo, Japan
[5] Univ Miyazaki, Org Promot Tenure Track, Miyazaki, Japan