,1, 杨红杰2, 张梦华1, 葛建军3, 马光辉,3, 张晓雪1, 王丹1, 尤震晨1, 胥磊1, 姜徽1, 赵番番1, 巨星1, 李云霞1Selection of Nucleus Herd for Simmental Cattle in Xinjiang Area
WEI Chen1, ZHAO Junjin2, HUANG XiXia,1, YANG HongJie2, ZHANG MengHua1, GE JianJun3, MA GuangHui,3, ZHANG XiaoXue1, WANG Dan1, YOU ZhenChen1, XU Lei1, JIANG Hui1, ZHAO FanFan1, JU Xing1, LI YunXia1通讯作者:
收稿日期:2018-05-28接受日期:2019-01-18网络出版日期:2019-03-01
| 基金资助: |
Received:2018-05-28Accepted:2019-01-18Online:2019-03-01
作者简介 About authors
魏趁,Tel：13139612131;E-mail：
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魏趁, 赵俊金, 黄锡霞, 杨红杰, 张梦华, 葛建军, 马光辉, 张晓雪, 王丹, 尤震晨, 胥磊, 姜徽, 赵番番, 巨星, 李云霞. 新疆地区西门塔尔牛核心群选择[J]. 中国农业科学, 2019, 52(5): 921-929 doi:10.3864/j.issn.0578-1752.2019.05.013
WEI Chen, ZHAO Junjin, HUANG XiXia, YANG HongJie, ZHANG MengHua, GE JianJun, MA GuangHui, ZHANG XiaoXue, WANG Dan, YOU ZhenChen, XU Lei, JIANG Hui, ZHAO FanFan, JU Xing, LI YunXia.
0 引言
【研究意义】20世纪50年代,我国先后从前苏联、奥地利、德国、法国等引入了乳肉兼用型西门塔尔牛,部分牛在新疆呼图壁种牛场进行纯繁,经过40多年培育出地域适应性较强的西门塔尔牛。目前新疆西门塔尔牛及高代杂种牛约60万头,是广大农牧民主要利用的品种,西门塔尔牛产乳、产肉性能较高且抗病力强、耐粗饲,已成为新疆农业产业发展重点方向。【前人研究进展】早在1943年HAZEL[1]提出了综合选择指数的概念,并在实际生产中实现了对个体综合选择指数值的选择。自1957年西门塔尔牛由国家引入后,1967—1979年一直处于保种阶段,1979—1980年正式开始对西门塔尔牛育种值估计的方法进行研究并对该群体进行选育[2],在1981—2000年许尚忠、陈幼春[3]等确定了中国西门塔尔牛乳肉兼用的育种目标将产奶量、乳脂率、外貌评分和体重纳入总性能指数进行选择,于2001年培育出中国西门塔尔牛。2001年任红艳[4]研究报道利用MTDFREML软件对中国西门塔尔牛305 d产奶量、乳脂率、乳蛋白率、体重及外貌评分进行遗传参数及育种值估计。赵静等[5,6,7,8,9]对中国西门塔尔母牛繁殖性状、体型性状、生产效率性状、健康性状、生产性状和肉用性状进行遗传参数估计。GOTZ 等[10]建议德系西门尔塔牛将产奶性状、产肉性状、健康性状、肢蹄性状、乳房系统等纳入总性能指数,在牛健康度方面尤其是使用年限的育种权重有了较大的提升。目前有很多国外****[11,12,13,14,15]对西门塔尔牛产奶性状、肉用性状、生长性状、繁殖性状等进行遗传参数和育种值估计。【本研究切入点】多年来新疆地区西门塔尔牛的遗传改良取得一定的成效,但缺少西门塔尔牛的遗传进展评价,通过对西门塔尔牛主要经济性状进行遗传评定以及核心群选择,加快西门塔尔牛育种进展,旨在为今后制定和优化适合新疆地区西门塔尔牛的育种方案提供理论依据。【拟解决的关键问题】本研究对西门塔尔牛305 d产奶量、乳脂率、乳蛋白率、乳糖率、总固体、体细胞评分、成母牛体重和外貌评分共8个性状进行遗传评定,分别通过TPI选择和单性状选择为公牛和在群母牛进行排队及建立核心母牛群,并对比利用TPI选择与单性状选择的差异,最终选择优秀的公畜和母畜进行繁殖、扩群,有助于提高牛群的综合性能水平。1 材料与方法
1.1 数据来源
数据主要来源于新疆呼图壁种牛场牧三场1975—2016年西门塔尔牛生产性能记录、1984—2016年乳成分记录（1984—2006年为场内乳成分记录、2008—2016年为DHI数据）、1988—2015年体重和外貌评定记录,包括西门塔尔牛305 d产奶量、乳脂率、乳蛋白率、乳糖率、总固体、体细胞数、成母牛体重、外貌评分共8个性状,DHI数据来源于新疆维吾尔自治区奶业办公室,西门塔尔牛的体重、外貌评分的数据严格按照《中国西门塔尔牛鉴定标准》进行测量和评定,成母牛体重为估测体重,其公式为体重（kg）=胸围（m）2×体软长（m）×90[16]。1.2 305d产奶量的校正
西门塔尔牛305 d产奶量用张文龙等[17,18] 研究的系数进行校正,将泌乳天数低于90 d的数据删除,超过305 d的泌乳天数用305 d实际累积的产奶量。1.3 体细胞数转换为体细胞评分
一般牛奶中体细胞数的分布频率显偏态分布,体细胞评分显正态分布,需将体细胞数转换为体细胞分,公式如下[19]：SCS=log2(SCC/105)+3
1.4 DHI数据平均值的计算
将西门塔尔牛测定日的乳脂率、乳蛋白率、乳糖率、总固体和体细胞评分转化为305 d的数据。转换公式如下：F=$\frac{\sum M}{N}$
式中,F为平均乳脂率（乳蛋白率、乳糖率、总固体和体细胞评分）,∑M为每一胎次测定日乳脂率总和（乳蛋白率、乳糖、总固体和体细胞评分）,N为该胎次测定日乳脂率（乳蛋白率、乳糖、总固体和体细胞评分）测定月份数[20,21]。
1.5 统计分析方法
利用DMU软件的DMUAI过程,采用多性状动物模型,通过求解混合模型方程组和运行AIREML可直接得到各方差组分的最准确估计值,得出固定效应估计值、各性状估计育种值。针对西门塔尔牛产各性状的动物模型如下：Y=Xb+Zu+e
式中,Y为性状的观察值向量;b为固定效应（胎次、产犊年份、产犊季节、产犊年龄嵌套于胎次）向量;u为动物个体加性遗传效应向量; X为固定效应关联矩阵;Z为加性遗传效应关联矩阵;e为残差效应向量。
模型假设前提条件：
E(y)=Xb, E(u)=0, E(e)=0, Var(a)=0, Var(a)=A2a, Var(e)=Iσ2e, COV(u, e′)=0。
1.6 总性能指数
本研究根据2003年中国西门塔尔牛国家标准中制定的总性能指数（TPI）公式进行计算,公式如下：TPI=[3×$\frac{{{M}_{B}}}{SD{{M}_{A}}}$+$\frac{{{F}_{B}}}{SD{{F}_{A}}}$+$\frac{{{T}_{B}}}{SD{{T}_{A}}}$+$\frac{{{W}_{B}}}{SD{{W}_{A}}}$]×50
式中,MB、FB、TB、WB分别是多性状混合模型同次估计的BLUP育种值,SDMA、SDFA、SDTA、SDWA分别是产奶量、乳脂率、外貌评分和体重估计的加性遗传标准差。
2 结果
2.1 各性状描述性统计分析
表1列出了西门塔尔牛各性状的观察值数、平均值、标准差、最大值和最小值等统计量。Table 1
表1
表1西门塔尔牛主要经济性状的描述统计量
Table 1
| 性状 Trait | 数据量 Records | 均值 Average | 标准差 SD | 变异系数 CV(%) | 最小值 Minimum | 最大值 Maximum |
|---|---|---|---|---|---|---|
| 305MY (kg) | 6413 | 5496.91 | 1547.01 | 28.14 | 2001.00 | 11740.00 |
| MFP (%) | 3991 | 4.14 | 0.82 | 19.84 | 1.31 | 14.04 |
| MPP (%) | 3220 | 3.32 | 0.43 | 13.04 | 1.54 | 7.89 |
| MLP (%) | 1744 | 4.75 | 0.36 | 7.57 | 1.96 | 5.44 |
| TS (%) | 1743 | 12.41 | 1.22 | 9.81 | 4.49 | 17.45 |
| SCS | 2145 | 4.27 | 2.03 | 47.17 | -1.32 | 12.08 |
| MCW (kg) | 2363 | 645.72 | 81.50 | 12.62 | 254.70 | 940.63 |
| TC (100) | 2042 | 76.61 | 3.00 | 3.91 | 75.00 | 86.00 |
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2.2 西门塔尔牛各性状的方差组分及遗传力
表2所示西门塔尔牛主要经济性状遗传力及方差组分估计结果,遗传力变化范围为0.09—0.60。305MY、TS和MCW属于高遗传力（h2>0.3）,MFP、MPP、MLP和TC属于中等遗传力（0.1<h2<0.3）,SCS属于低遗传力（h2<0.1）。Table 2
表2
表2西门塔尔牛主要经济性状方差组分及遗传力估值
Table 2
| 性状Trait | $\sigma^{2}_{a}$. | $\sigma^{2}_{e}$ | $\sigma^{2}_{p}$ | $h^{2}_{a}$±SE |
|---|---|---|---|---|
| 305MY | 808838.49 | 1225067.02 | 2033905.52 | 0.39±0.02 |
| MFP | 0.10 | 0.56 | 0.66 | 0.15±0.02 |
| MPP | 0.02 | 0.15 | 0.17 | 0.12±0.03 |
| MLP | 0.01 | 0.11 | 0.12 | 0.12±0.02 |
| TS | 0.42 | 0.86 | 1.28 | 0.32±0.03 |
| SCS | 0.34 | 3.41 | 3.75 | 0.09±0.02 |
| MCW | 4107.57 | 2638.08 | 6745.65 | 0.60±0.02 |
| TC | 1.51 | 6.37 | 7.89 | 0.19±0.03 |
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2.3 西门塔尔牛各性状的遗传趋势
图1所示为西门塔尔牛305MY、MFP、MPP、SCS和MCW性状估计育种值随个体出生年份变化趋势。对于305MY性状而言,1974—1998年间遗传趋势变化不明显,1999—2007年间呈下降趋势,从2008—2012年呈明显的上升趋势。对于MFP和MPP这两个性状而言,1974—2006年间遗传趋势略呈下降趋势,从2007—2013年呈明显的呈上升趋势。对于SCS性状而言,1974—2000年间遗传趋势呈上升趋势;2001—2012年间总体呈下升趋势,有的年间呈上升趋势,变化不稳定。对于MCW性状而言,1974—2007年间遗传趋势上下波动较大,变化不是很明显;2008—2011年间呈明显的上升趋势。图1
新窗口打开|下载原图ZIP|生成PPT图1西门塔尔牛各性状育种值随出生年份变化趋势
Fig. 1Trends of EBVs of each trait for Simmental cattle with birth year
2.4 TPI公式的建立
TPI是依据相对经济重要性加权值,并将产奶量、乳脂率、成母牛体重、外貌评分的估计育种值（estimated breeding value,EBV）综合考虑,它主要反映育种目标性状的综合育种值,公式如下：TPI=[3×$\frac{M{{Y}_{B}}}{899}$+$\frac{F{{P}_{B}}}{0.32}$+$\frac{MC{{W}_{B}}}{61}$+$\frac{T{{C}_{B}}}{1.23}$]×50
其中,MYB、FPB、BWB、MCWB、TCB分别是六性状混合模型同次估计的BLUP育种值,899、0.32、64、1.23分别是多性状混合模型同次估计的产奶量、乳脂率、乳蛋白率、成母牛体重和外貌评分的加性遗传标准差,公式中 50 为指数系数,各性状经济权重为3﹕1﹕1﹕1。
2.5 核心群的选择
表3为西门塔尔牛不同分组的TPI值、各性状育种值和表型值,1975—2016年间使用西门塔尔公牛共计241头,从表中可以看出排名第一的公牛TPI值为552.45,排名前十名公牛平均TPI值为 383.41;从表中可以看出排名前十名的母牛平均TPI值为401.15,314头在群母牛群平均TPI值为70.24,从在群母牛中筛选出100头核心母牛群平均TPI值为214.91;从表中可以看出100头核心群母牛305MY、MFP、MCW和TC表型值均值分别为7 095.10 kg、4.13%、696.53 kg和76.73,与在群母牛群平均表型值相比要高。Table 3
表3
表3西门塔尔牛不同分组的TPI值、各性状育种值和表型值
Table 3
| 分组Groups | 305MY | MFP | MCW | TC | TPI |
|---|---|---|---|---|---|
| 第一名公牛（育种值） Breeding value of first bull | 2377.76 | 0.21 | 152.16 | 0.10 | 552.45 |
| 前十名公牛（平均育种值） Average breeding value of top 10 bulls | 1581.39 | 0.25 | 86.56 | 0.32 | 383.41 |
| 前十名母牛（平均育种值） Average breeding value of top 10 cows | 1969.41 | -0.16 | 61.85 | 1.27 | 401.15 |
| 100头核心母牛群（平均育种值） Average breeding value of top 100 nucleus herd cows | 1011.89 | 0.18 | 28.62 | -0.12 | 214.91 |
| 在群母牛群（平均育种值） Average breeding value of herd cows | 330.17 | 0.11 | 7.74 | -0.19 | 70.24 |
| 100头核心群母牛（平均表型值） Average phenotype value of top 100 nucleus herd cows | 7095.10kg | 4.13% | 696.53kg | 76.73 | - |
| 在群母牛群（平均表现值） Average phenotype value of herd cows | 5989.12kg | 4.08% | 694.95kg | 76.61 | - |
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图2西门塔尔牛不同选择下各性状育种值,从图中可以看出只选择305MY这一性状,不同分组的305MY育种值高于TPI选择,MFP育种值高于TPI选择,MCW和TC育种值均低于TPI选择;只选择MPP这一性状,不同分组的305MY育种值均低于TPI选择（除了第一名公牛育种值）,MFP育种值高于TPI选择,MCW和TC育种值均低于TPI选择。
图2
新窗口打开|下载原图ZIP|生成PPT图2西门塔尔牛不同选择下各性状育种值及表型值
1为第一名公牛育种值;2为前十名公牛平均育种值;3为前十名母牛平均育种值;4为100头核心母牛群平均育种值
Fig. 2Breeding values and phenotypic values of different traits under different selections of Simmental cattle
1 is breeding value of first bull;2 is average breeding value of top 10 bulls;3 is average breeding value of top 10 cows;4 is average breeding value of top 100 nucleus herd cows
3 讨论
3.1 西门塔尔牛各性状的描述性统计及遗传力分析
本研究中西门塔尔牛各性状的表型均值与其他群体相比不一致,其主要原因由于群体大小和遗传背景的不同[10,22-23]。LUDOVIC等[24]研究报道罗马尼亚弗莱维赫牛305MY、MFP 和MPP的均值分别为 5 252.1 kg,3.93%,3.29%,与本研究结果相比要低。ATAKAN[25]研究报道了土耳其法系西门塔尔牛305MY、MFP和MPP的均值分别为5 956.5 kg、3.55%和2.93 %,305MY要高于本研究结果,其他性状低于本研究结果。本研究结果表明西门塔尔牛产奶性状、体重和外貌评分的遗传力范围在0.09—0.60。范大有等[6]研究报道中国西门塔尔牛305 d产奶量、乳脂率、乳蛋白率、体细胞评分的遗传力分别为0.35、0.20、0.21、0.25,属于中高等遗传力,与本研究结果一致（除体细胞评分）。任红艳等[4]研究报道中国西门塔尔牛305 d产奶量、乳脂率、体重和外貌评分的遗传力为0.35、0.20、0.45、0.18,与本研究相比除305 d产奶量和外貌评分的遗传力相差不大,体重的遗传力较低。汪春乾等[7]研究报道中国西门塔尔牛成年母牛体重的遗传力为0.47,与本研究结果相比略低。ZDENKO等[26]研究报道利用测定日模型估计西门塔尔牛和荷斯坦奶牛的体细胞评分的遗传力分别为0.21和0.15,比本研究结果要高。RODICA等[27]研究报道利用测定日模型估计蒙贝利亚牛10—305 d奶产量的遗传力范围在0.36—0.44,与本研究结果相比略高。ERIKA 等[28]研究报道利用动物模型估计意大利西门塔尔牛体型外貌评分、产奶量、乳脂量、乳蛋白量的遗传力分别为0.18、0.18、0.13、0.17,除产奶量外,其他性状与本研究结果相差不大。不同群体遗传力不同其主要原因是由于群体大小、遗传背景、估计方法的不同,同时要具有较大的样本量、完整的系谱以及稳定良好的饲养环境等条件,才能提高遗传力估计的准确性,尤其在不同牛场和地区,在实际生产中数据量少,系谱错误、不完整等潜在的因素是不可避免的,也会引起遗传力估计值偏低等负面影响。
3.2 西门塔尔牛各性状的遗传趋势分析
本文对西门塔尔牛各性状遗传趋势进行分析,在1974—2008 年间各性状育种值变化不大,到了2008年以后305MY、MFP、MPP和MCW呈上升趋势,SCS呈下降趋势,说明近年来对西门塔尔牛这些性状选育及遗传改良有了一定的成果,其中主要原因之一是2007年以后中国引进外来资源如法系西门塔尔牛和德系西门塔尔牛种公牛冻精和胚胎,对本地西门塔尔牛进行杂交改良,加快了遗传进展。任红艳[4]对1980—2000年中国西门塔尔牛产奶性状（305 d产奶量、乳脂率、乳蛋白率）、体重及外貌评分进行了育种值估计,其结果表明产奶量遗传趋势呈上升趋势,乳脂率和乳蛋白率变化不大,成母牛体重和外貌评分呈下降趋势,与本研究结果不一致。MIROSLAV等[22]研究报道克罗地亚西门塔尔牛305 d奶产量、乳脂率、乳蛋白率的育种值,随着年份的增加305 d奶产量的遗传趋势呈上升趋势,说明近年来克罗地亚对西门塔尔牛产奶性状选育及遗传改良取得了较好的成果。3.3 西门塔尔牛TPI的分析
本研究根据中国西门塔尔牛TPI公式,对种公牛、大群母牛群和在群母牛群进行育种值排队,其中排在第一位的种公牛是法系西门塔尔牛,排在前10位的种公牛主要为法系西门塔尔牛和德系西门塔尔牛;从314头在群母牛群中筛选出100头核心母牛,其各性状的表型值均高于在群母牛,该牧场以100头核心母牛群为基础,通过选择优秀的种公牛进行繁育、扩群。根据个体后裔估计公牛TPI值,该牧场可以按照不同的需求进行配种,比如某个公牛的TPI 值较低,反而乳脂率育种值很高,仅产奶量育种值比较低,在进行选育时就可以选择产奶量育种值高的母牛进行交配,得到产奶量、乳脂率均高的后代,达到选种选配的目的,从而给生产者带来经济效益。在西门塔尔牛今后的育种工作中,可以加强对TPI值高的种公牛的使用程度,以获得更多生产性能高的后代。3.4 TPI选择与单性状选择的差异分析
本研究通过对比不同分组下305MY性状选择、MPP性状选择和TPI选择各性状育种值,得出TPI选择要优于单性状选择,说明在生产实践中综合选择指数更实用。由于该场主要以出售牛奶为主要的经济来源,为了提高乳品质,后续需将乳蛋白率加入TPI中。在产奶性状中,乳脂率和乳蛋白率可以作为信息性状间接选择育种目标,主要是因为它们之间有较强的正遗传相关,所以乳蛋白率是西门塔尔牛选育的重要指标[29,30]。在2003年李俊雅[31]研究报道了中国西门塔尔牛乳用性状、肉用性状、次级性状的经济权重比为1﹕1﹕2,这表明中国西门塔尔牛育种目标与欧洲国家相比一致。2016年薛景龙[32]报道了中国肉用西门塔尔牛生长发育性状、胴体性状、繁殖性状的经济权重比为2﹕1﹕3,这表明中国肉用西门塔尔牛主要以繁殖性状为主。任红艳等[33]综述了德国弗莱维赫牛( 德系西门塔尔牛) 遗传评定方法,其中阐述了德系西门塔尔牛总性能指数主要包括乳用性能（产奶量、乳脂量和乳蛋白量）、肉用性状（净日增重、胴体产肉率、胴体等级和屠宰率）和适应性（使用年限、泌乳持续力、繁殖力、产犊难易度、死胎率、体细胞数和泌乳速度）,经济权重为37.9﹕16.5﹕45.6,而中国乳用西门塔尔牛育种体系还需进一步研究探索,后续研究还需将功能性状纳入总性能指数。BIRGIT等[34]研究表明为了优化澳大利亚西门塔尔牛育种目标,将乳用性状、肉牛性状和健康性状经济价值分别为39%、13%和48%。目前很多国家奶牛育种体系相对比较健全,如美国、加拿大、德国、荷兰、意大利、法国等国,已将功能性状纳入总性能指数中,如繁殖力、长寿性、饲料转化率等[35],其中功能性状可以降低饲养成本来增加生产收益,所以中国西门塔尔牛育种体系还有很大的改进空间。4 结论
西门塔尔牛305MY、TS和MCW属于高遗传力,MFP、MPP、MLP和TC属于中等遗传力,SCS属于低遗传力;对高遗传力性状容易改良,采用个体选择就可以获得较高的遗传进展。经过多年选育呼图壁种牛场西门塔尔牛305MY、MPF、MPP和MCW育种值明显增加,SCS呈下降趋势,说明近年来对西门塔尔牛的选育及遗传改良有了一定的成果。通过比较TPI选择和单性状选择的差异,证明了在生产实践中选择指数法更实用,牧场可加大TPI值高的种公牛的使用程度,并以100头核心母牛群为基础进行繁育、扩群,可以提高该场全群西门塔尔牛生产水平,加快群体遗传进展,最终提高牧场经济利益。参考文献 原文顺序
文献年度倒序
文中引用次数倒序
被引期刊影响因子
DOI:10.1007/BF02982970URLPMID:17247099 [本文引用: 1]
TH E idea of a yardstick or selection index for measuring the net merit of breeding animals is probably almost as old as the art of animal breeding itself. In practice several or many traits influence an animal’s practical value, although they do so in varying degrees. The information regarding different traits may vary widely, some coming from an animal’s relatives and some from the animal’s own performance for traits which are expressed once or repeatedly during its lifetime. LUSH (1935) emphasized that permanent improvement from phenotypic selection is proportional to the additively genetic (heritable) fraction of the observed variance and that this varies for different traits. DOBZHANSK(1Y9 37)s uggested “that most, and possibly all, genes have manifold effects.” These factors make wise selection a complicated and uncertain procedure; in addition fluctuating, vague, and sometimes erroneous ideals often cause the improvement resulting from selection to be much less than could be achieved if these obstacles were overcome.
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[D]. 北京: 中国农业科学院,
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[D]. Beijing: Chinese Academy of Agricultural Sciences,
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DOI:10.3969/j.issn.1000-5684.2002.04.025URLMagsci [本文引用: 1]
应用动物模型并借助MT-DFREML方法估计了中国西门塔尔母牛主要繁殖性状的遗传参数,得到母牛的配妊时间与产犊间隔的遗传力分别为0.065和0.047;母牛配妊时间、产犊间隔与305d产奶量表型相关系数分别为0.17和0.15,遗传相关系数分别为0.45和0.35;配妊时间与产犊间隔的表型相关系数为0.27,遗传相关系数为0.33。结果表明:环境因素对母牛主要繁殖性状影响非常显著,母牛繁殖性状为低遗传力性状,各性状间存在不同程度的相关。
DOI:10.3969/j.issn.1000-5684.2002.04.025URLMagsci [本文引用: 1]
应用动物模型并借助MT-DFREML方法估计了中国西门塔尔母牛主要繁殖性状的遗传参数,得到母牛的配妊时间与产犊间隔的遗传力分别为0.065和0.047;母牛配妊时间、产犊间隔与305d产奶量表型相关系数分别为0.17和0.15,遗传相关系数分别为0.45和0.35;配妊时间与产犊间隔的表型相关系数为0.27,遗传相关系数为0.33。结果表明:环境因素对母牛主要繁殖性状影响非常显著,母牛繁殖性状为低遗传力性状,各性状间存在不同程度的相关。
DOI:10.3321/j.issn:0366-6964.2008.08.004URLMagsci [本文引用: 2]
<FONT face=Verdana>利用6个种畜场1980—2000年间1 634头母牛的繁殖性状和生产性状记录，以及现场测定的泌乳速度和乳成分含量等资料，对中国西门塔尔母牛的4类次级性状:繁殖性状(产犊间隔、空怀天数、妊娠期)、体型性状（整体评分、后肢、乳房体型性状：前乳房附着、后乳房宽度、后乳房高度、乳头位置、乳房均衡、乳房静脉）、生产效率性状（泌乳速度、使用年限）、健康性状（体细胞数评分）和生产性状（产奶量、乳脂量、乳蛋白量、乳脂率、乳蛋白率）共19个性状进行了遗传统计分析。应用动物模型并借助MTDFREML方法估计了上述19个性状的遗传参数，得到它们的遗传力分别为：0.08、0.07、0.08、0.16、0.15、0.41、0.11、0.07、0.10、0.23、0.18、0.42、0.13、0.25、0.35、0.32、0.23、0.20和0.21。泌乳速度与生产性状为负的遗传相关（-0.22～-0.10），与使用年限和整体评分有着较高的遗传相关，分别为0.87和0.61；体细胞数与生产性状以及使用年限存在着不利相关；使用年限与泌乳速度、整体评分、产奶量为正遗传相关（0.61、0.14、0.42），与体细胞数存在有利相关（遗传相关为-0.23）。乳房性状与生产性状、次级性状都有着较密切的关系，其中以前乳房附着、后乳房宽度、乳头位置和乳房静脉与这两种性状的关系最为密切，其遗传相关为-0.36～1.00，表明对乳房性状进行选择能够使生产性状与次级性状得到改良。环境对次级性状的影响较大，不同饲养管理制度和泌乳阶段是影响泌乳速度、使用年限和体细胞数的主要环境因素。</FONT>
DOI:10.3321/j.issn:0366-6964.2008.08.004URLMagsci [本文引用: 2]
<FONT face=Verdana>利用6个种畜场1980—2000年间1 634头母牛的繁殖性状和生产性状记录，以及现场测定的泌乳速度和乳成分含量等资料，对中国西门塔尔母牛的4类次级性状:繁殖性状(产犊间隔、空怀天数、妊娠期)、体型性状（整体评分、后肢、乳房体型性状：前乳房附着、后乳房宽度、后乳房高度、乳头位置、乳房均衡、乳房静脉）、生产效率性状（泌乳速度、使用年限）、健康性状（体细胞数评分）和生产性状（产奶量、乳脂量、乳蛋白量、乳脂率、乳蛋白率）共19个性状进行了遗传统计分析。应用动物模型并借助MTDFREML方法估计了上述19个性状的遗传参数，得到它们的遗传力分别为：0.08、0.07、0.08、0.16、0.15、0.41、0.11、0.07、0.10、0.23、0.18、0.42、0.13、0.25、0.35、0.32、0.23、0.20和0.21。泌乳速度与生产性状为负的遗传相关（-0.22～-0.10），与使用年限和整体评分有着较高的遗传相关，分别为0.87和0.61；体细胞数与生产性状以及使用年限存在着不利相关；使用年限与泌乳速度、整体评分、产奶量为正遗传相关（0.61、0.14、0.42），与体细胞数存在有利相关（遗传相关为-0.23）。乳房性状与生产性状、次级性状都有着较密切的关系，其中以前乳房附着、后乳房宽度、乳头位置和乳房静脉与这两种性状的关系最为密切，其遗传相关为-0.36～1.00，表明对乳房性状进行选择能够使生产性状与次级性状得到改良。环境对次级性状的影响较大，不同饲养管理制度和泌乳阶段是影响泌乳速度、使用年限和体细胞数的主要环境因素。</FONT>
DOI:10.3969/j.issn.1672-352X.2004.04.008URL [本文引用: 2]
利用中国西门塔尔牛6个国家级种畜场1980～2000年间生长性状记录,对中国西门塔尔牛的初生重、断奶重、周岁重、18月龄重和成年母牛体重共5个性状进行遗传统计分析,应用动物模型、借助MT-DFREML方法估计上述性状的遗传参数,并考虑母体效应.结果表明,中国西门塔尔牛出生重、断奶重、周岁重、18月龄重和成年母牛体重的遗传力分别是0.32、0.11、0.27、0.36和0.47;生长性状的直接加性遗传效应和母体加性遗传效应呈较高强度的负相关(-0.39～-0.99);相邻年龄段内生长性状间的直接加性遗传效应相关值较高,而时间跨度大的年龄段生长性状间相关值相对较低;周岁重与18月龄重、成年母牛体重间的直接加性遗传相关、母体加性遗传相关值均较高.
DOI:10.3969/j.issn.1672-352X.2004.04.008URL [本文引用: 2]
利用中国西门塔尔牛6个国家级种畜场1980～2000年间生长性状记录,对中国西门塔尔牛的初生重、断奶重、周岁重、18月龄重和成年母牛体重共5个性状进行遗传统计分析,应用动物模型、借助MT-DFREML方法估计上述性状的遗传参数,并考虑母体效应.结果表明,中国西门塔尔牛出生重、断奶重、周岁重、18月龄重和成年母牛体重的遗传力分别是0.32、0.11、0.27、0.36和0.47;生长性状的直接加性遗传效应和母体加性遗传效应呈较高强度的负相关(-0.39～-0.99);相邻年龄段内生长性状间的直接加性遗传效应相关值较高,而时间跨度大的年龄段生长性状间相关值相对较低;周岁重与18月龄重、成年母牛体重间的直接加性遗传相关、母体加性遗传相关值均较高.
DOI:10.11843/j.issn.0366-6964.2016.09.009URL [本文引用: 1]
本研究旨在对出生于2008-2013年的中国西门塔尔牛肉用群体的重要经济性状进行遗传参数和方差组分估计,该群体大小为2 939头。采用非求导约束最大似然法估计遗传力、遗传相关和方差组分。结果显示,初生重、断奶重、出栏重、胴体重、屠宰率和净肉率的遗传力估计值分别为0.48、0.44、0.43、0.38、0.31、0.39。其中,初生重和断奶重的遗传相关估计结果为0.57,出栏重和胴体重的遗传相关为0.94,屠宰率和净肉率的遗传相关为0.89。该群体的生长和屠宰相关性状均属于中高遗传力性状,且性状之间具有较高的遗传相关。本研究对中国西门塔尔牛肉用群体重要经济性状的遗传参数做了系统评估分析,为将来制定育种方案和遗传评估奠定基础。
DOI:10.11843/j.issn.0366-6964.2016.09.009URL [本文引用: 1]
本研究旨在对出生于2008-2013年的中国西门塔尔牛肉用群体的重要经济性状进行遗传参数和方差组分估计,该群体大小为2 939头。采用非求导约束最大似然法估计遗传力、遗传相关和方差组分。结果显示,初生重、断奶重、出栏重、胴体重、屠宰率和净肉率的遗传力估计值分别为0.48、0.44、0.43、0.38、0.31、0.39。其中,初生重和断奶重的遗传相关估计结果为0.57,出栏重和胴体重的遗传相关为0.94,屠宰率和净肉率的遗传相关为0.89。该群体的生长和屠宰相关性状均属于中高遗传力性状,且性状之间具有较高的遗传相关。本研究对中国西门塔尔牛肉用群体重要经济性状的遗传参数做了系统评估分析,为将来制定育种方案和遗传评估奠定基础。
DOI:10.19556/j.0258-7033.2018-06-043URL [本文引用: 1]
本研究利用呼图壁种牛场2002-2011年的西门塔尔母牛的体高、体长、胸围、腿围、管围及产奶量性状记录,通过DMU软件对西门塔尔母牛的主要经济性状及产奶性状进行遗传参数估计.结果表明:西门塔尔母牛腿围、管围和产奶量的遗传力为0.33～0.42,属于中等遗传力;体高、体长和胸围的遗传力为0.56～0.67,属于高等遗传力.
DOI:10.19556/j.0258-7033.2018-06-043URL [本文引用: 1]
本研究利用呼图壁种牛场2002-2011年的西门塔尔母牛的体高、体长、胸围、腿围、管围及产奶量性状记录,通过DMU软件对西门塔尔母牛的主要经济性状及产奶性状进行遗传参数估计.结果表明:西门塔尔母牛腿围、管围和产奶量的遗传力为0.33～0.42,属于中等遗传力;体高、体长和胸围的遗传力为0.56～0.67,属于高等遗传力.
DOI:10.1016/j.livsci.2015.05.019URL [本文引用: 2]
Systematic breeding of polled Fleckvieh (Simmental) cattle in Bavaria dates back until 1974 when the first polled cow was purchased for breeding purposes. Until 1985 three polled bulls and two more polled dams were purchased and from 1984 on the first homozygous bulls were produced via embryo transfer. Until 1990 the polled allele was only common in beef strains of the Fleckvieh breed. At the beginning of the 1990s the first polled alleles were introduced into the dairy herd of the State Research Farm in Grub. This research farm acted as the nucleus for the introgression of the polled allele in the dual-purpose lines of the Fleckvieh breed. Since 2003 polled calves in all herds under milk recording were systematically recorded and the polled phenotype was regularly examined by employees of the Bavarian State Research Institute for Agriculture. At the same time a systematic cooperation with Bavarian herdbook organizations and AI-stations was established. Between 2000 and 2011 in total 193 polled bulls were raised at the Bavarian State Research Institute for Agriculture (LfL), of which 37 entered AI-stations. Currently the dual-purpose population of Fleckvieh comprises 7055 polled cows and 175 polled AI-sires. In 2013 and 2014 approximately 22,000 and 32,000 polled calves were born per year. The analysis of relationships showed that the polled bulls are less related to the horned population and that until now the introgression has caused negligible amounts of additional inbreeding. It is expected that in 2021 the proportion of polled cows in the Fleckvieh dual-purpose population will be at 10.5% of all cows if the progression of polledness continues linearly. However, it can be expected that the progression will accelerate due to the new possibilities offered by genomic preselection of polled AI-bulls. First experiences with genomically preselected polled bulls show a very good acceptance among breeders.
DOI:10.1111/j.1744-7348.2010.00451.xURL [本文引用: 1]
This study was done to evaluate the relationships between some features that affect milk yield in Simmental cattle and was aimed to determine the direct or indirect effects of these features on 305 days milk yield. In this study, the direct and indirect relationships between Simmental cattle's number of lactation (X1), the age of animal (X2), calving season (X3), dry period (X4), age in the fir...
DOI:10.2527/jas.2012-6126URLPMID:23881688 [本文引用: 1]
Stayability to consecutive calvings was selected as a measure of cow longevity in the Canadian Simmental population. Calving performance data on 188,579 cows and culling information from the Total Herd Reporting System were used to determine whether a cow stayed in a herd for her second and later (up to the eighth) calvings, given that she had calved as 2 yr old. Binary records (n = 1,164,319) were analyzed with animal linear and threshold models including fixed effects of year of birth by season of birth by parity number and age of cow at first calving by parity number and random effects of contemporary group (CG) defined as herd of birth within year by season, animal additive genetic effect, and a cow permanent environmental (PE) effect. All random effects were Legendre polynomial regressions of the same order, defined on the scale from second to the eighth calving. Bayesian methods with Gibbs sampling were used to estimate covariance components and genetic parameters for random effects of models and selected variables on the longitudinal scale. Bayes factors and analyses of mean squared error and correlation between observed and predicted observations indicated that the linear model with regressions of order 3 was most plausible for generating the current data compared with a fixed regression and other random regression (both linear and threshold) models of order up to 4. Estimates of variances for all random effects from the best fitting model changed with the calving number. Estimates of heritability decreased in time: from 0.35 (SD = 0.006) for stayability to second calving to 0.13 (SD = 0.004) for stayability to the eighth calving. Variance due to PE effect constituted the largest part of the total variance of stayability for all longitudinal points followed by genetic and CG components. Genetic effects of stayability to different calvings were relatively highly correlated, from 0.62 (SD = 0.011) to 0.99 (SD = 0.001), and correlation decreased with the time span between calvings. Correlations for PE and CG effects showed similar trends. Animal genetic effect seemed to be less variable on the longitudinal scale compared with other random effects of the model. The first 2 principal components explained from 95% (PE effects) to 99% (genetic effect) of the total variance. The overall level of genetic stayability curve correlated well (from 0.87 to 0.99, with SD < 0.006) with genetic stayability to different calvings and therefore could be used as a single criterion in selection for stayability.
DOI:10.2478/aoas-2014-0073URL [本文引用: 1]
The effect of systematic and continuous environmental factors on milk performance traits over standard lactations in 2805 Simmental cows was evaluated using the general linear model. The systematic factors included the effect of farm or breeding area, calving season, year of birth, season of birth, lactation group and their interactions. The continuous factor analysed was the effect of age at first conception. The effect of farm, lactation group and calving season on standard lactation milk performance was found to be highly significant (P<0.01), excepting the effect of calving season on milk fat percent in standard lactations which showed statistical significance (P<0.05). The interactions between year and season of birth, farm and calving season, and farm and lactation group had a highly significant effect (P<0.01) on all performance traits studied. Age at first conception, as a continuous factor, had a highly significant effect (P<0.01) on milk yield and milk fat percent, and a non-significant effect on milk fat yield. The model used to correct the performance traits over standard lactations for the effect of systematic factors was highly significant (P<0.01). The variance of the model accounted for 20.06 and 37.31% of the total variance of milk fat yield and milk fat percent, respectively. The resulting coefficients of determination (R2) ranged from 0.20 for milk fat yield to 0.37 for milk fat percent.
URL [本文引用: 1]
The objective of this study was to compare EBVs, reliability and genetic parameters in random regression models with Legendre polynomials using structures of data sets with different minimum number of test days in lactation. The original data base was edited in order to prepare for subsets by deleting cows that did not have at least 4, 6, 8 or 10 test day (TD) records in lactation. The... [Show full abstract]
DOI:10.2527/jas2017.1865URLPMID:29293732 [本文引用: 1]
react-text: 254 Analysis of whole genome haplotype diversity can characterize the genetic population structure and selection signals. Prior to commencing studies of haplotypes from breed-distinct populations, however, it is important to consider the purity of breeds, which will influence the accuracies of conclusions about haplotype sharing. Here we studied a dataset comprising over 30,000 animals genotyped... /react-text react-text: 255 /react-text [Show full abstract]
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[D]. 乌鲁木齐市: 新疆农业大学,
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DOI:10.3969/j.issn.1007-8614.2013.03.002URL [本文引用: 1]
为了探讨新疆西门塔尔牛的泌乳曲线规律,并为新疆西门塔尔牛制定305d产奶量的校正系数。选用了Wood不完全伽玛函数模型、Nelder逆多项式、多项式回归(六次)、Ali-Schaeffer模型和Wilmink模型分别对西门塔尔牛泌乳曲线进行了拟合,以期选出最优的拟合模型,为新疆西门塔尔牛制定出较为准确的产奶量校正系数。结果表明,多项式回归模型(六次)为新疆呼图壁种牛场西门塔尔牛最佳泌乳曲线模型,对各个胎次泌乳曲线的拟合效果都较为理想,R2均达到0.9以上,应用此模型计算得到了新疆西门塔尔牛305d产奶量的校正系数。
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DOI:10.3969/j.issn.1007-8614.2013.03.002URL [本文引用: 1]
为了探讨新疆西门塔尔牛的泌乳曲线规律,并为新疆西门塔尔牛制定305d产奶量的校正系数。选用了Wood不完全伽玛函数模型、Nelder逆多项式、多项式回归(六次)、Ali-Schaeffer模型和Wilmink模型分别对西门塔尔牛泌乳曲线进行了拟合,以期选出最优的拟合模型,为新疆西门塔尔牛制定出较为准确的产奶量校正系数。结果表明,多项式回归模型(六次)为新疆呼图壁种牛场西门塔尔牛最佳泌乳曲线模型,对各个胎次泌乳曲线的拟合效果都较为理想,R2均达到0.9以上,应用此模型计算得到了新疆西门塔尔牛305d产奶量的校正系数。
DOI:10.1016/S0749-0720(15)30622-8URLPMID:8242460 [本文引用: 1]
Abstract Heredity influences both clinical mastitis and somatic cell score. Intramammary infection is the major cause of elevated somatic cell score. A nationwide program of genetic evaluation of dairy cattle for somatic cell score is being developed. Proper selection of artificial insemination sires, considering their genetic merit for both milk production and somatic cell score, will reduce the genetic increase in mastitis susceptibility that accompanies selection for high production.
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[D]. Urumqi: Xinjiang Agricultural University,
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DOI:10.1111/j.1744-7348.2010.00451.xURL [本文引用: 1]
This study was done to evaluate the relationships between some features that affect milk yield in Simmental cattle and was aimed to determine the direct or indirect effects of these features on 305 days milk yield. In this study, the direct and indirect relationships between Simmental cattle's number of lactation (X1), the age of animal (X2), calving season (X3), dry period (X4), age in the fir...
DOI:10.5713/ajas.16.0588URLPMID:5411826 [本文引用: 1]
Aim of the current comparative study was to evaluate production outputs, reproduction efficiency and functional traits in dual-purpose Fleckvieh and Braunvieh cows, reared under temperate European conditions. A data-set from 414 Fleckvieh and 42 Braunvieh cows and 799 lactations was analysed. ID tag number, milk yield per milking session, number of steps/interval and milk conductivity were recorded and collected daily using AfiMilk 3.076 A-DU software (Afimilk Ltd., Kibbutz, Israel). Production and milk quality data were taken from the results of the official performance recordings and the reproductive outputs of cows were recorded by the research stations veterinarians. Comparisons between the two genotypes were carried out using the one way analysis of variance protocol, with categorical factor being considered the breed of cows. All the statistical inferences were carried out using Statistica software (StatSoft Inc., Tulsa, OK, USA). Fleckvieh cows significantly outperformed (p≤0.05) the Braunvieh herd, with average milk yields of 5,252.1±35.79 kg and 4,897.6±128.94 kg, respectively. Age at first calving was significantly (p≤0.01) influenced by the breed, with Fleckvieh heifers being more precocious (32.8±0.29 mo) compared to those of Braunvieh breed (35.7±0.84 mo). Reproduction efficiency as defined by the number of inseminations per gestation, calving interval, dystocia, days dry and days open, was not influenced by genotype (p>0.05). Incidences of sub-clinical mastitis, clinical mastitis, lameness and abortions were not influenced by the breed factor (p>0.05). Stayability of cows was significantly (p≤0.001) influenced by genotype, with Braunvieh cows having an average age at culling of 117.88±11.78 months compared to 90.88±2.89 months in Fleckvieh. Overall, results have shown that genotype significantly influenced milk yield, age at first calving and longevity.
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DOI:10.1186/1297-9686-44-10URL [本文引用: 1]
The objective of this study was to estimate genetic parameters and environmental effects on somatic cell count in Croatian dairy cows. Data consisted of 861,417 test-day records for Simmental and 656,272 for Holstein cows. For Simmental breed, number of animals in pedigree was 123,199, while pedigree file for Holstein breed included 94,294 animals. A single-trait repeatability fixed regression test-day model was used to estimate genetic parameters. Fixed effects in the model were parity and calving season. Days in milk was fitted using Ali-Schaeffer lactation curve nested within parity. Age at first calving was modelled as quadratic regression. Direct additive genetic effect, herd, herd-test-date, and permanent environmental effect of cow within parity were included in the model as random effects. Variance components were estimated using Residual Maximum Likelihood method as implemented in the VCE-6 program. Estimated heritabilities were 0.21 for Simmental and 0.15 for the Holstein breed. Permanent environmental effect explained 19 % of phenotypic variation in Simmental and 20 % in Holstein breed. Herd and herd-test-date accounted for another 9 % and 5 % of variability for Simmental breed. The effects of herd and herd-test-date explained 10 % and 5 % of phenotypic variance in Holstein breed.
URL [本文引用: 1]
The objective of this study was to compare EBVs, reliability and genetic parameters in random regression models with Legendre polynomials using structures of data sets with different minimum number of test days in lactation. The original data base was edited in order to prepare for subsets by deleting cows that did not have at least 4, 6, 8 or 10 test day (TD) records in lactation. The... [Show full abstract]
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DOI:10.2298/BAH1102127PURL [本文引用: 1]
The basis for selection work is knowledge of the quality of bull sires used for conception, as well as how the major traits are passed on to the progeny. BLUP method (Best Linear Unbiased Prediction) is the basis of the most favourable solution for evaluation of additive gene value in cattle production, and it is implemented in various variants depending on the structure of data used. This research included 2.121 Simmental first cavers under control, with lactations completed within one year. All first calvers were located on holdings of individual agricultural producers on the territory of the Republic of Serbia. Evaluation of the bull breeding value for lactation duration, milk production, milk fat yield, yield of 4% FCM and percentage of milk fat, was carried out by using the mixed model (BLUP), the calculation included random effect of bull sire and fixed effect of the region, year and season of calving. In this study, bull sires which had in two or three regions over 20 daughters - first calvers of Simmental breed. Number of first calving heifers ranged from 22 to 215 animals per bull sire. By using BLUP method in evaluation of breeding value of bulls in terms of yield of milk, milk fat, content of milk fat and 4% FCMI and by ranking, results were obtained showing superiority and inferiority of breeding males.
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[D]. 长春: 吉林农业大学,
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DOI:10.3969/j.issn.1004-4264.2007.08.021URL [本文引用: 1]
为扩大测定群,提高遗传进展,德国早在2000年就开始和奥地利进行弗莱维赫牛联合育种,合并的群体以DEA的形式参与国际种公牛遗传评定.目前DEA弗 莱维赫牛群体主要包括3部分,即德国巴伐利亚、德国巴登威滕堡和奥地利.其中,巴伐利亚的弗莱维赫牛群体最大(约占总群体的80%),生产性能也高于其它 两个群体.
DOI:10.3969/j.issn.1004-4264.2007.08.021URL [本文引用: 1]
为扩大测定群,提高遗传进展,德国早在2000年就开始和奥地利进行弗莱维赫牛联合育种,合并的群体以DEA的形式参与国际种公牛遗传评定.目前DEA弗 莱维赫牛群体主要包括3部分,即德国巴伐利亚、德国巴登威滕堡和奥地利.其中,巴伐利亚的弗莱维赫牛群体最大(约占总群体的80%),生产性能也高于其它 两个群体.
DOI:10.3168/jds.2015-9445URLPMID:26387020 [本文引用: 1]
Abundant evidence from the medical, veterinary, and animal science literature demonstrates that there is substantial room for improvement of the clarity, completeness, and accuracy of reporting of intervention studies. More rigorous reporting guidelines are needed to improve the quality of data available for use in comparisons of outcomes (or meta-analyses) of multiple studies. Because of the diversity of factors that affect reproduction and the complexity of interactions between these, a systematic approach is required to design, conduct, and analyze basic and applied studies of dairy cattle reproduction. Greater consistency, clarity, completeness, and correctness of design and reporting will improve the value of each report and allow for greater depth of evaluation in meta-analyses. Each of these benefits will improve understanding and application of current knowledge and better identify questions that require additional modeling or primary research. The proposed guidelines and checklist will aid in the design, conduct, analysis, and reporting of intervention studies. We propose an adaptation of the REFLECT (Reporting Guidelines for Randomized Controlled Trials for Livestock and Food Safety) statement to provide guidelines and a checklist specific to reporting intervention studies in dairy cattle reproduction. Furthermore, we provide recommendations that will assist investigators to produce studies with greater internal and external validity that can more often be included in systematic reviews and global meta-analyses. Such studies will also assist the development of models to describe the physiology of reproduction.
DOI:10.19305/j.cnki.11-3009/s.2016.07.007URL [本文引用: 1]
总性能指数（TotalPerformanceIndex，TPI）和终身效益指数（LifetimeProfitIndex,LPI）分别是美国和加拿大奶牛育种中对荷斯坦牛进行遗传评估的选择指数。本文主要通过分析TPI和LPI公式各性状指数变化及对美国TPI遗传增量的变化情况，来对北美奶牛育种目标的发展变化及遗传进展情况进行简述，为中国荷斯坦公牛及牧场奶牛育种工作提供一些参考和借鉴。
DOI:10.19305/j.cnki.11-3009/s.2016.07.007URL [本文引用: 1]
总性能指数（TotalPerformanceIndex，TPI）和终身效益指数（LifetimeProfitIndex,LPI）分别是美国和加拿大奶牛育种中对荷斯坦牛进行遗传评估的选择指数。本文主要通过分析TPI和LPI公式各性状指数变化及对美国TPI遗传增量的变化情况，来对北美奶牛育种目标的发展变化及遗传进展情况进行简述，为中国荷斯坦公牛及牧场奶牛育种工作提供一些参考和借鉴。
