摘要
本研究旨在通过直肠温度(RT)测定,探究夏季热应激情况下北京地区牛群RT变化规律及其对产奶量的影响。试验实测了2014年7-8月份北京地区3个奶牛场上午、下午奶牛RT、体况评分(BCS)、牛舍内温度,并收集各牛场DHI报告,利用固定模型分析不同场、胎次、泌乳阶段及BCS对RT、测定日产奶量的影响。结果表明:1)803头奶牛的上午、下午RT和日体温差平均值及标准差分别为(38.69±0.45)℃、(38.98±0.50)℃、(0.29±0.53)℃;2)不同场间RT存在差异,泌乳第Ⅰ阶段(1~50d)的奶牛RT显著高于其他泌乳阶段(P<0.05),BCS显著影响下午RT(P<0.05);3)下午RT与BCS平方均对测定日产奶量有显著影响(P<0.05),下午RT每升高1℃,平均日产奶量减少约1.26kg·头^(-1)。夏季热应激情况下北京地区奶牛RT较高,且下午RT过高可导致测定日产奶量降低。因此,管理人员可通过加强防暑降温措施降低体温,并注意控制体况,着重关注泌乳前期牛;RT可作为奶牛热应激相关研究的指标,并为抗热应激奶牛选育计划提供间接选择信息。
This study was designed to measure cows＇ rectal temperature（RT）,and to explore the pattern of dairy cows＇ RT and effect of RT on milk yield under the heat stress during summer in Beijing area.Dairy cows＇ morning afternoon RT,body condition score（BCS）and ambient temperature in the barn were measured from 3scaled dairy farms in Beijing area from July to August,2014,and DHI data of researched dairy farms was collected.The effects of farm,parity,stage of lactation and BCS on RT and test-day milk yield were analyzed using a fixed model.The result showed that：1）The simple statistics of 803cows＇ morning,afternoon RT and their difference were（38.69±0.45）℃,（38.98±0.50）℃ and（0.29±0.53）℃,respectively;2）RT among different farms was significantly different,the RT level at the first stage of lactation（day 1to 50）was significantly higher than that at other stages（P〈0.05）,BCS had significant effect on afternoon RT（P〈0.05）;3）Both afternoon RT and squared BCS had significant effect on test-day milk yield（P〈0.05）,the average daily milk yield decreased 1.26 kg with per unit increase of after-noon RT.These results indicated that afternoon RT was relatively higher and might cause loss of test-day milk yield under heat stress during summer in Beijing area.Therefore,herd managers should strengthen cooling measures in summer in Beijing,monitor cows＇ BCS,and pay more attention to early lactating dairy cows.RT can be used as an indicator in the study related to heat stress in dairy cows,and RT could provide indirect information for breeding plan for selecting heat tolerance ability in dairy cow.
出处
《畜牧兽医学报》
CAS
CSCD
北大核心
2016年第4期745-751,共7页
ACTA VETERINARIA ET ZOOTECHNICA SINICA
基金
现代农业(奶牛)产业技术体系建设专项资金(CARS-37)
国家自然科学基金(31172191)
"十二五"科技支撑计划(2011BAD28B02)
2014年北京市科技计划"奶牛抗热应激综合措施研究与科技示范"(Z151100001015012)
中央高校基本科研业务费专项资金项目
长江学者和创新团队发展计划(IRT1191)
