2015 Volume 58 Issue 2 Pages 239-245
It is thought that the variation in oxytocin function within the brain is related to the individual difference in stress sensitivity. In the present study, we investigated the relationship of oxytocin receptor (OXTR) gene promoter region polymorphisms and temperament score during stressful situation in Japanese Brown beef cow (Kumamoto line). Two types of polymorphisms (D and S) in OXTR gene promoter region detected by PCR and gel electrophoresis was utilized in this analysis. The temperament score during blood sampling and body weight measurement in unusual manner tended to be higher (more struggling with human handling) in the D type than in the S type. In the D type, there was strong negative correlations between temperament score and age of months (total score during body weight measurement: r2 = 0.7755, P < 0.001; total score during blood sampling and body weight measurement: r2 = 0.6685, P < 0.001), which means that the temperament score in D type became lower as they get older. It was concluded that the two base repeat sequence polymorphisms of OXTR promoter region might affect OXTR gene function in some way.