三江源区高寒草场泌乳牦牛冷季补饲精料对其产奶量及乳中矿物质元素含量的影响  

Effects of Supplementary Concentrate in Cold Season on Milk Yield and Milk Mineral Element Contents in Lactating Yaks in Alpine Pastures in Sanjiangyuan Region

作　　者：周义秀 郝力壮[1] 刘书杰[1] ZHOU Yixiu;HAO Lizhuang;LIU Shujie(Qinghai Academy of Science and Veterinary Medicine of Qinghai University,Key Laboratory of Plateau Grazing Animal Nutrition and Feed Science of Qinghai Province,State Key Laboratory of Plateau Ecology and Agriculture,Qinghai Plateau Yak Research Center,Xining 810016,China)

机构地区：[1]青海大学畜牧兽医科学院,青海省高原放牧家畜动物营养与饲料科学重点实验室,省部共建三江源生态与高原农牧业国家重点实验室,青海高原牦牛研究中心,西宁810016

出　　处：《动物营养学报》2020年第9期4194-4204,共11页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：国家重点研发计划(2016YFD0500504);国家自然科学基金(31660673);中国科学院“西部之光”人才培养引进计划(1-7);青海省高原放牧家畜动物营养与饲料科学重点实验室奖励项目(2020-ZJ-Y08);国家重点基础研究发展计划(973前期项目)(2012CB722906)。

摘　　要：本试验旨在阐明三江源区高寒草场泌乳牦牛冷季补饲精料对其产奶量及乳中矿物质元素含量的影响。选取自然放牧状态下胎次和体况一致的50头健康泌乳牦牛,随机分为5组,即:A组(自然放牧)、B组(自然放牧+补饲0.25 kg/d精料)、C组(自然放牧+补饲0.50 kg/d精料)、D组(自然放牧+补饲1.00 kg/d精料)、E组(自然放牧+补饲1.50 kg/d精料),记录从2018年11月至2019年4月泌乳牦牛每月产奶量,采用火焰原子吸收法每月对5组牦牛乳及牧草中9种矿物质元素[钾(K)、钠(Na)、钙(Ca)、镁(Mg)、铁(Fe)、锰(Mn)、锌(Zn)、钴(Co)、铜(Cu)]含量进行了测定。结果表明:1)牧草中Mn含量在各月份之间无显著性差异(P>0.05),其余矿物质元素含量在各个月份之间均有显著性差异(P<0.05),其中K、Ca、Fe、Zn和Cu含量随月份推移呈先降低后升高再降低后上升趋势,Mg和Co含量呈先降低后升高趋势,Na含量呈先降低后升高再降低趋势,而Mn含量则呈缓慢上升趋势。2)2018年11月各组之间产奶量无显著性差异(P>0.05),其余5个月不同精料补饲量对泌乳牦牛产奶量有显著性影响(P<0.05),2018年12月D组产奶量最高,2019年1—4月E组产奶量最高,且显著高于A组(P<0.05)。3)补饲精料对牦牛乳中矿物质元素含量的影响较大,K、Na、Mg和Co含量均为E组最高,且显著高于A组(P<0.05);Ca含量在2018年11月、2019年2月、2019年3月表现为E组显著高于A组(P<0.05);Fe含量除在2018年12月以D组最高外,其余月份均为E组显著高于A组(P<0.05);Mn含量除2019年2月和4月B组最高外,其余月份均为E组显著高于A组(P<0.05);Zn含量除2019年2月D组最高外,其余月份E组显著高于A组(P<0.05);Cu含量除2019年2月C组最高外,其余月份E组显著高于A组(P<0.05)。4)牦牛产奶量与精料补饲量呈线性相关关系,其拟合方程为Y=0.22 X+0.508(r=0.749);乳中除Ca和Mg含量外,K、Na、Fe、Mn、Zn、Co和Cu含量均与精料补饲量呈线性相关�The purpose of this study was to clarify the effects of supplementary concentrate in cold season on milk yield and mineral element contents in lactating yaks in alpine pastures in Sanjiangyuan region.The 50 healthy lactating yaks with the same parity and body condition under natural grazing were randomly divided into five groups,namely:group A(natural grazing),group B(natural grazing+supplementary 0.25 kg/d concentrate),group C(natural grazing+supplementary 0.50 kg/d concentrate),group D(natural grazing+supplementary 1.00 kg/d concentrate),group E(natural grazing+supplementary 1.50 kg concentrate),recording monthly milk yield of lactating yaks from November 2018 to April 2019.The contents of nine minerals(K,Na,Ca,Mg,Fe,Mn,Zn,Co and Cu)of yak milk and forage in five groups were determined by flame atomic absorption spectrometry monthly.The results showed as follows:1)there was no significant difference in Mn contents in forage among the months(P>0.05),and other mineral contents had significant differences among the months(P<0.05),the contents of K,Ca,Fe,Zn,and Cu showed a trend of decreasing first,then increasing,then decreasing,and then increasing with the passage of months.The contents of Mg and Co showed a trend of decreasing first and then increasing.The Na content showed a trend of decreasing first,then increasing and then decreasing.The Mn content was increased slowly.2)There was no significant difference in milk yield among the groups in November 2018(P>0.05),and the different supplementary concentrate for the remaining five months had a significant effect on the milk yield of lactating yaks(P<0.05).In December 2018,group D had the highest milk yield,and from January to April 2019,group E had the highest milk yield,which was significantly higher than group A(P<0.05).3)Supplementary concentrate has a great influence on the contents of mineral elements in yak milk.The contents of K,Na,Mg and Co were the highest in group E,which significantly higher than that in group A(P<0.05).The Ca content in group E was si

关 键 词：冷季 牦牛乳 饲粮 产奶量 矿物质 

分 类 号：S823[农业科学—畜牧学]