Department of Animal Science, Texas A&M University, College Station, TX 77843-2471, USA.
Department of Animal Science, Texas A&M University, College Station, TX 77843-2471, USA.
Anim Reprod Sci. 2021 Sep;232:106820. doi: 10.1016/j.anireprosci.2021.106820. Epub 2021 Jul 30.
This experiment was conducted to evaluate reproductive and productive responses of Bos indicus and B. taurus beef cows according to body condition score (BCS) at initiation of the annual breeding season. Non-pregnant, suckling multiparous cows were assigned to a fixed-time artificial insemination treatment regimen followed by natural service. Cows were classified as having a BCS < 5.0 (B. taurus, n = 158; B. indicus, n = 248) or BCS ≥ 5.0 (B. taurus, n = 173; B. indicus, n = 122). Calving rate was greater (P < 0.03) in cows with a BCS ≥ 5.0 (93.7 % and 85.1 % in B. taurus, 83.6 % and 73.3 % in B. indicus), which also calved earlier (P < 0.01) compared with cows with a BCS < 5.0. Cows with a BCS ≥ 5.0 weaned more (P ≤ 0.05) calves compared with those with a BCS < 5.0, which were older (P ≤ 0.04) and weighed more (P ≤ 0.09) at weaning (258 and 252 kg in B. taurus, 213 and 203 kg in B. indicus). Kilograms of calf weaned/cow in the breeding herd were greater (P ≤ 0.03) in cows with a BCS ≥ 5.0 compared with those with a BCS < 5.0 (221 and 200 kg in B. taurus, 159 and 129 d in B. indicus). Collectively, cows with a BCS ≥ 5.0 at initiation of the breeding season had greater reproductive and overall productivity during a cow-calf cycle, and these outcomes were observed in B. taurus and B. indicus cowherds.
本实验旨在评估根据年度配种季节开始时的身体状况评分（BCS），对印度瘤牛和瘤牛肉牛的繁殖和生产性能。非妊娠、哺乳期的经产奶牛被分配到定时人工授精处理方案后，再进行自然交配。奶牛被分为 BCS<5.0（瘤牛，n=158；印度瘤牛，n=248）或 BCS≥5.0（瘤牛，n=173；印度瘤牛，n=122）。BCS≥5.0 的奶牛产犊率更高（P<0.03），其中瘤牛的产犊率为 93.7%和 85.1%，印度瘤牛的产犊率为 83.6%和 73.3%，BCS≥5.0 的奶牛产犊更早（P<0.01）。BCS≥5.0 的奶牛断奶的小牛更多（P≤0.05），与 BCS<5.0 的奶牛相比，断奶的小牛年龄更大（P≤0.04），体重更重（P≤0.09）（瘤牛为 258 和 252 千克，印度瘤牛为 213 和 203 千克）。繁殖群中断奶的小牛/奶牛的体重更大（P≤0.03），BCS≥5.0 的奶牛比 BCS<5.0 的奶牛更大（瘤牛为 221 和 200 千克，印度瘤牛为 159 和 129 天）。总的来说，在配种季节开始时 BCS≥5.0 的奶牛在牛犊周期中具有更高的繁殖和整体生产力，这些结果在瘤牛和印度瘤牛牛群中都观察到了。
