肉用牛群における黒毛和種子牛の下痢症感受性について

Abstract

The susceptibilities to diarrhea of calves of 4 breeds, Japanese Black, Japanese Red (Kumamoto), Aberdeen Angus and Hereford, were observed in a beef herd in Hokkaido. The incidence rates of diarrhea in those breeds were 79.2, 31.6, 63.3 and 38.3% respectively and there were significantly different (p=0.001) among 4 breeds. Japanese Black and Aberdeen Angus calves tended to be more sensitive against diarrhea than Japanese Red or Hereford. There was no significantly different among 4 breeds in the age in days at the first diarrhea and the period of treatment.Beef cattle calves are mainly reproduced in small farms which keep small numbers of cows in Japan. Though the cost for production should be expected to be decreased, effective methods such as grazing or mass production are not established yet, especially for Japanese Black calves. Calf diarrhea is one of big problems for mass production of beef cattle2). However, there have been few studies of the susceptibility to diarrhea in the grazing environment for Japanese Black calves.In the present study, we observed the susceptibilities to diarrhea of calves of 4 breeds, Japanese Black, Japanese Red (Kumanoto), Aberdeen Angus and Hereford, in a grazing herd.