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作 者:刘帅 魏家琳 马玉林 杨思锐 马佳莹 曹志军[1] LIU Shuai;WEI Jia-lin;MA Yu-lin;YANG Si-rui;MA Jia-ying;CAO Zhi-jun(State Key Laboratory of Animal Nutrition,College of Animal Science and Technology,China Agricultural University,Beijing 100193)
机构地区:[1]中国农业大学动物科学技术学院/动物营养学国家重点实验室,北京100193
出 处:《中国奶牛》2022年第3期57-62,共6页China Dairy Cattle
基 金:中国农业大学2115人才工程(00109017)。
摘 要:后备奶牛从出生到首次产犊泌乳之前并不能产生直接的经济效益,因此牧场都希望后备奶牛能尽早地配种、产犊,以更快地投入生产,产生经济价值,使得后备奶牛适时配种和产犊成为了奶牛饲养中至关重要的环节。调研结果显示,我国规模化牧场后备奶牛平均初配月龄为14.1月龄,平均初产月龄为23.8月龄,并且从2015-2019年,平均初配月龄和初产月龄都呈现逐年提前的趋势。初配和初产月龄的提前也反映了我国规模化牧场管理水平的提高。此外,头胎牛305d产奶量是牧场的另一重要关注点。调研结果发现,73.3%的头胎牛305d产奶量为7~9t,平均为8.79t。影响头胎牛产奶量的因素众多,相关问题还有待进一步研究。Calves and Heifers do not bring direct economic benefits to dairy farms before first calving. Dairy farms expect dairy replacements to be inseminated and calve earlier, in order to produce milk quickly and make them economically profitable. Thus, the reasonable time of first calving and service of heifers has become a key point in management of dairy cows. The results showed that the first calving and service age of heifers had been brought forward from 2015 to 2019 annually with the average first breeding reaching at 14.1 month, and the average first calving age reaching at 23.8 month. Moreover, such earlier first calving and service age could reflect the improvement of management level of China large-scale dairy farms. In addition, 305 d milk yield for first lactation cows is another key point in farms. The results showed that the average of 305 d milk yield for first lactation was 8.79tons, and that of 73.3% ranged from 7~9 tons. There are many factors affecting milk yield in first lactation cows,which need to be studied further.
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