荷斯坦牛头胎患隐性乳房炎次数和乳中体细胞评分对2胎体细胞评分的影响  

Effects of the Number of Subclinical Mastitis and Somatic Cell Score in Milk of Parity 1 on Somatic Cell Score of Holstein Cows for Parity 2

作　　者：夏予馨 梁艳 王海洋 郭梦玲 周部 代旭 杨章平[1] 毛永江[1] XIA YuXin;LIANG Yan;WANG HaiYang;GUO MengLing;ZHOU Bu;DAI Xu;YANG ZhangPing;MAO YongJian(College of Animal Science and Technology/Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education,Yangzhou 225009,Jiangsu)

机构地区：[1]扬州大学动物科学与技术学院/教育部农业与农产品安全国际合作联合实验室,江苏扬州225009

出　　处：《中国农业科学》2022年第20期4052-4064,共13页Scientia Agricultura Sinica

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“六大人才高峰”项目(NY-093);江苏现代农业(奶牛)产业技术体系项目(JATS[2018]300)。

摘　　要：【目的】奶牛不同胎次间生理状态具有关联性。研究旨在探究荷斯坦牛头胎患隐性乳房炎(subclinical mastitis, SCM)次数和乳中体细胞评分(somatic cell score, SCS)对2胎SCS的影响,为提高牧场奶牛2胎泌乳性能和原料乳品质提供科学依据。【方法】收集江苏13个牛场2015—2020年荷斯坦牛同时具有1—2胎的DHI测定日记录共162 509条,先用Excel2019对测定日记录进行前期处理和筛选,采用SAS(Ver 9.4)的混合模型探究牛场规模、采样年度、产犊季节、泌乳月、头胎患SCM次数和头胎各泌乳阶段SCS(泌乳期平均、泌乳前期、泌乳中期和泌乳后期)对2胎荷斯坦牛乳中SCS的影响,同时分析了头胎牛患SCM次数和各泌乳阶段SCS与2胎各泌乳月SCS的相关性。【结果】牛场规模、采样年度、产犊季节、泌乳月、头胎患SCM次数和头胎不同泌乳阶段平均SCS均对荷斯坦牛2胎乳中SCS均有极显著影响(P<0.01)。其中,规模在5 000头以上的牛场SCS显著低于其他规模的牛场(P<0.05);2020年荷斯坦牛SCS显著高于其他采样年度(P<0.05);春夏季产犊的奶牛SCS显著高于其他产犊季节(P<0.05),冬季产犊的奶牛SCS显著低于其他产犊季节(P<0.05);第9、10泌乳月乳中SCS显著高于其他泌乳月(P<0.05),第2泌乳月乳中SCS显著低于其他泌乳月(P<0.05)。头胎患SCM为2次及以下的奶牛,2胎各泌乳月SCS呈现先下降后上升的趋势;头胎患3次及以上SCM的奶牛,2胎各泌乳月SCS波动较大。头胎牛泌乳期平均SCS、泌乳前期、泌乳中期、泌乳后期各为0、1、2、3时,2胎各泌乳月呈现先下降后上升的趋势;头胎泌乳期平均SCS大于3时,2胎各泌乳月SCS波动较大。整体来说,随头胎牛患SCM次数及各泌乳期平均SCS的增加,2胎牛各泌乳月SCS也逐渐升高。头胎患SCM次数及各泌乳阶段SCS与2胎各泌乳月SCS均呈极显著正相关(P<0.01),头胎泌乳期平均SCS与2胎各泌乳月SCS的相关系数最大(0.238),头�【Objective】There was correlation between physiological status of different parities of cows. The objective of this research was to explore the effect of the number of subclinical mastitis(SCM) and somatic cell score(SCS) in milk of parity 1 on SCS of Holstein cows for parity 2. 【Method】This study collected 162 509 DHI records of Holstein cows with parity 1 and 2 from 2015 to 2020 in 13 farms in Jiangsu Province. Excel 2019 was used to pre-process and filter DHI records firstly. The mixed model of SAS(Ver 9.4) was used to explore the effects of farm size, sampling year, calving season, lactation month, the number of SCM on parity 1and each average lactation stage of SCS on parity 1 on SCS of parity 2. At the same, the correlation coefficients between the number of SCM and the SCS for each lactation stage of parity 1 with SCS in each lactation month for parity 2 of Holstein cows were calculated.【Result】The farm size, sampling year, calving season, lactation month, the number of SCM on parity 1 and average SCS on parity 1 in different periods had extremely significant effects on the SCS of parity 2(P<0.01). Among them, SCS with farm size over 5 000 was lower than other farm size(P<0.05). SCS in 2020 was higher than other sampling year(P<0.05). SCS of cows calving in summer and spring was higher than other calving season(P<0.05), while SCS of cows calving in winter was lower than other calving season(P<0.05). SCS in the 9th and 10th lactation month was higher than other lactation months(P<0.05), while SCS in the second lactation month was lower than other lactation months(P<0.05). The SCS in each lactation month of parity 2showed downward firstly and then upward trend for the cows with the number of SCM less than 2 for parity 1. The SCS for parity 2in each lactation month fluctuated greatly for the cow with the number of SCM with 3 or more than in parity 1. When the average lactation of SCS, early lactation of SCS, mid lactation of SCS, and late lactation of SCS for the cows in parity 1 were 0, 1, 2, and

关 键 词：隐性乳房炎 体细胞评分 荷斯坦牛 胎次 

分 类 号：S823[农业科学—畜牧学]