Comparison on the Growth Characteristics between Calves of Two Different Japanese Beef Breeds Suckled by Japanese Shorthorn Dams
JARQ : Japan Agricultural Research Quarterly
The growth characteristics of five male Japanese Black calves that were produced by embryo transfer to, born from, and nursed by Japanese Shorthorn surrogate dams (BS-group) were compared with those of five male Japanese Shorthorn calves that were delivered from dams of the same breed after natural mating (SS-group). The birth weights of the BS-group calves were lower (P < 0.01) than those of the SS-group calves. During the first two months, the daily weight gain of the SS-group calves was greater (P < 0.05) than that of the BS-group calves. However, between the third and fourth months, the daily weight gain of the BS-group calves was greater (P > 0.05). During the first two months, the chest girth was smaller (P < 0.05) in the BS-group calves than in the SS-group calves, but was similar in both groups by the age of four months. Although the gains in chest depth, body length, and withers height of the BS-group calves were inferior to those of the SS-group calves during the first two months, these gains were all superior to those of the SS-group calves during the next two months. Trends in age-related changes in plasma total cholesterol concentrations significantly differed between both groups. The SS-group dams lost much more weight during early lactation than did the BS-group dams (P > 0.05). No difference was observed in the blood components of the dams in either group. In summary, the BS-group calves were relatively small at birth, and their growth performance was inferior to that of the SS-group calves during the first two months. At around two months of age, the Japanese Black embryo-transfer calves began to suckle larger amounts of milk from their surrogate dams and showed rapid growth that was comparable to that of larger framed Japanese Shorthorn calves.
|Manabu YAMAGUCHI Akira WATANABE Naoki TAKENOUCHI Hiroyuki SUZUKI Masatoshi MATSUZAKI
Japanese Black cattle
|Japan International Research Center for Agricultural Sciences