摘要
为探究荷斯坦牛日产奶量和体细胞评分(SCS)变化趋势及其影响因素,本研究利用最小二乘法对江苏某牛场2010-2019年415386条荷斯坦牛DHI据进行分析。结果表明:不同胎次、产犊季节、测定年度、测定月份和泌乳月对荷斯坦牛日产奶量和体细胞评分有极显著影响(P<0.01)。其中,荷斯坦牛第2胎日产奶量最高(33.63 kg),显著高于其他胎次(P<0.05);荷斯坦牛SCS在第1胎最低(1.98),显著低于其他胎次(P<0.05)。荷斯坦牛冬季产犊时日产奶量最高(34.02 kg),夏季产犊时SCS最高(2.40),均显著高于其他季节(P<0.05)。在整个泌乳期,荷斯坦牛日产奶量先是逐渐上升,在第2-3泌乳月达到泌乳高峰后开始下降;SCS呈先下降,在第2-3泌乳月达到最低值后上升的变化趋势。综上结果表明,荷斯坦牛在夏季热应激时泌乳性能受到严重影响。因此,该牛场最好在秋冬季节产犊比较适宜,可以提高奶牛产奶量和乳品质。
In order to explore the variation trend of daily milk yield and somatic cell score(SCS)of Holstein cows and its influencing factors,the least square method was used to analyze the DHI data of 415386 Holstein cows in a dairy farm in Jiangsu province from 2010 to 2019 in this study.The results showed that the daily milk yield and SCS of cows were significantly affected by different parities,calving seasons,measured years,tested-months and lactation stages(P<0.01).The daily milk yield was the highest in the second parity(33.63 kg),significantly higher than that of other parities(P<0.05).The SCS of cows were the lowest in the first parity(1.98),significantly lower than other parities(P<0.05).During winter,the daily milk yield of calving cows was the highest(34.02 kg),while the SCS was the highest in summer(2.40),and significantly higher than that in other seasons(P<0.05).During the whole lactation stage,the daily milk yield of cows firstly increased,and then began to decline after reaching the peak of lactation in second or third milking month.SCS firstly decreased,and then increased after reaching the lowst level in second or third milking month.The research shows that the daily milk yield and SCS of Holstein cows were significantly affected during the heat stress in summer.Therefore,it is suitable for the cows to calve in autumn and winter,which can improve the milk yield and quality of milk.
作者
郭梦玲
王海洋
梁艳
李明勋
杨章平
毛永江
GUO Mengling;WANG Haiyang;LIANG Yan;LI Mingxun;YANG Zhangping;MAO Yongjiang(College of Animal Science and Technology,Yangzhou University,Yangzhou Jiangsu 225009,China)
出处
《家畜生态学报》
北大核心
2020年第11期42-47,共6页
Journal of Domestic Animal Ecology
基金
国家自然科学基金(31972555)
江苏省高等学校自然科学研究项目(18KJA230003)
江苏省农业自主创新基金项目[CX(17)1005]
江苏现代农业(奶牛)产业技术体系项目(JATS[2018]300)
江苏省企业研究生工作站资助项目。
关键词
产奶量
体细胞评分
影响因素
荷斯坦牛
milk yield
somatic cell score(SCS)
influencing factors
Holstein cows
作者简介
郭梦玲(1996-),女,江苏丹阳人,在读硕士,研究方向:奶牛遗传育种。E-mail:2867021229@qq.com;通讯作者:毛永江(1974-),男,贵州江口人,教授,博士生导师,主要从事奶牛遗传育种研究。E-mail:cattle@yzu.edu.cn。
