Questionnaire investigation to clarify the occurrence rate and characteristics of maternal rejection behavior in Japanese black cattle (Bos taurus).

We conducted a questionnaire investigation among breeding farmers to clarify the actual conditions of maternal rejection in Japanese Black cattle. We asked keeping experience of maternal rejective cows and compared occurrence patterns, rejective behavior manners, birth assistance methods, colostrum feeding method for calves, parity and rearing conditions of the cows. We found that 24% of the farms had kept rejective cows and 6% of the cows in these farms indicated maternal rejections. The most common occurrence pattern was 'Occurred from the first birth (65.6%)' and behavior manner was performing no maternal grooming with aggressive behavior (75%). Almost all the farmers assisted in each parturition (P < 0.05). There was not a significant difference among the colostrum feeding methods, but a significant difference in the rearing conditions of the cows, except for the cows with no data (P < 0.005). The parity of the rejective cows did not significantly differ in association with rejective behavior manners, birth assistance methods, colostrum feeding methods or rearing conditions. These results suggest that the occurrence rate of maternal rejection in Japanese Black cattle was approximately 6% and many of the rejective cows continuously performed no maternal grooming with aggressive behavior.