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[目的]为了研究荷斯坦牛体型线性性状之间及线性性状与305d产奶量之间的表型相关。[方法]选择40头第三胎健康荷斯坦泌乳牛,按9分制评分方法对15个体型性状进行评分,对功能分之间、功能分与305d校正产奶量之间进行相关性回归分析。[结果]表明：305d校正产奶量与臀宽、胸宽、体深、前房附着、整体评分、乳头长度之间成极显著正相关（P〈0．01）;经自变量的筛选,建立了305d校正产奶量（Y）与胸宽（X2）、体深（X3）、臀宽（X6）、前房附着（X9）、后房高度（X10）、乳头位置（X14）之间的回归方程Y=-5529．945＋59．456X2＋3．024X3—3．069X6＋70．173X9＋19．834X10-8．892X14,R^2=0．9231。[结论]依据上述六个性状可以预测荷斯坦奶牛的产奶量。 相似文献
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奶牛体型线性评定,是对奶牛体况进行无偏见评定的一种方法（储明星等,1996）.1986年,师守堃等将线性鉴定技术引入我国,并于1987年提出了将线性评分转化为功能评定,计算部位评分和整体评分.1995年中国奶牛协会颁发了《中国荷斯坦牛体型线性鉴定实施方案（试行）》.本文将主要按体躯容积、乳用特性、一般外貌、泌乳系统四大特征性状分15个重点性状进行评定分析. 相似文献
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《中国奶牛》2017,(10)
本研究选择了宁夏5个千头以上规模养殖场,依据《中国荷斯坦牛体型鉴定规程》(修订),以9分制对1260头荷斯坦牛进行了体型线性鉴定;采用SPSS11.0软件统计分析了鉴定牛只的五大部位20个描述性状和总体得分性状的表型参数,旨在为宁夏荷斯坦牛体型性状的遗传改良提供基础数据。结果表明:尻角度、尻宽、蹄踵深度、后肢后视、悬韧带、后房高度和后房宽度等性状与理想最佳线性评分差距较大。建议以此鉴定结果为依据,在今后的奶牛遗传选育工作中,对尻部、泌乳系统等部位的性状进行重点改良,选择适合的优秀验证种公牛,制定合理可行的选种选配方案,加快宁夏规模奶牛场高产奶牛遗传改良进展。 相似文献
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体型外貌性状是奶牛重要的选种指标,是奶牛保持高产、稳产、健康长寿的关键所在。本研究的目的在于探寻上海地区荷斯坦牛体型外貌与产奶性状的相互关系。、随机选取上海市28个奶牛场总计871头第二泌乳期荷斯坦母牛作为研究对象,记录并测定其305d产奶量、乳脂率、乳蛋白率3个产奶性状,体型外貌性状采用9分制评分结果．利用相关分析方法确定体型总分及7个体型外貌性状与各产奶性状之间的关系,结果表明,体型总分与305d产奶量、乳脂率呈极显著正相关（P〈O．01）;体躯容量性状和产奶量呈极显著正相关：肢蹄性状与乳脂率、乳蛋白率呈极显著正相关,与产奶量显著正相关（P〈O．05）;尻部性状与乳脂率呈显著正相关．。最终得出肢蹄、体躯容量、尻部性状是影响荷斯坦牛产奶性状的最主要因素,体型外貌鉴定评分对于筛选高产、优质荷斯坦母牛及选种选配工作具有指导意义。 相似文献
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安徽荷斯坦牛的体型线性评定分析 总被引：10，自引：0，他引：10
本文根据 1996年中国奶牛协会颁布的《中国荷斯坦牛体型线性鉴定实施方案 (试行 )》 ,采用线性评定 1～ 5 0分制 ,对安徽荷斯坦牛进行体型线性评定。结果表明 ,在一级线性性状中 ,体高、胸宽、尻宽、后房高度、乳头长度的评分随胎次增加而增加 ,而前房附着、乳房深度、后房高度的评分随胎次增加而减少。安徽荷斯坦牛平均体高段 137～139cm ,尻宽性状有显著的地区差异 (P <0 .0 5 ) ,在后房高度、乳头长度性状上不同地区表现一致且上乘 ,在乳房深度、前房附着性状上的表现存在着明显的地区差异 (P <0 .0 5 ) ,且均未达到奶牛体型的理想结构 相似文献
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旨在估计山东省荷斯坦奶牛体型性状遗传参数,为育种方案制定提供参考。本研究收集了山东省2010—2020年间的144个牛场31 963头头胎中国荷斯坦母牛的20个体型性状记录,其中性状评分由线性分转为功能分,将场、泌乳月、产犊月龄、鉴定员效应为固定效应,以个体的加性遗传效应作为随机效应,利用 DMU 软件,采用AI-REML结合EM算法并配合动物模型进行遗传参数估计。结果表明,体型性状的遗传力属于中等偏低水平,其估计值变化范围为0.049(后肢侧视)到 0.282(棱角性),性状间的遗传相关范围为-0.558(前乳头位置与乳房深度)至0.717(蹄踵深度与蹄角度)。体躯容量各性状间的遗传相关范围为0.118 (体深与体高)至0.461(胸宽与腰强度);尻角度与尻宽的遗传相关为-0.251;肢蹄各性状间的遗传相关范围为-0.035(蹄踵深度与后肢后视)到 0.717(蹄踵深度与蹄角度);泌乳系统各性状间的遗传相关范围为-0.558 (前乳头位置与乳房深度)至0.587(悬韧带与前乳房附着)。另外,体型性状的遗传力估计标准误在查找的系谱世代数为3的情况下为最小,这可能是由于系谱数据完整性的限制导致了该种情况,具体还需要进一步验证。加强对体型性状中遗传力较高且与泌乳系统遗传相关较强性状的选择,有利于奶牛生产性能的提高。另外,在本研究数据中,使用前3代系谱估计的遗传力标准误最小,因此,利用前3代系谱估算遗传参数可能较佳。 相似文献
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Relationships between Longevity and Linear Type Traits in Holstein Cattle Population of Southern Africa 总被引：1，自引：0，他引：1
Relationships between longevity and linear type traits were estimated using data on 34,201 cows with lifetime information and linear type scores. The longevity trait considered was the number of lactations initiated and the linear type traits were rump height, body depth, angularity, rear udder height, fore udder attachment, udder depth, fore teat placement and fore teat length. Fixed effects included in the models were herd year, season of calving and herd-date of classification-classifier and days in milk. Age at first calving and age at classification were included as linear and quadratic covariates. Heritability estimates were low for longevity and moderate for most type traits except rump height and fore teat length. All the phenotypic correlations between longevity and the linear type traits were slightly positive (0.01 to 0.09) except the relationships with rump height and fore teat length which were -0.01 and -0.02, respectively. Genetic correlations between longevity and udder traits as well as angularity were moderate to high and positive (0.22 to 0.48). The only notable negative genetic correlations were longevity with body depth and fore teat length (-0.15 and -0.07, respectively). The genetic correlations suggest that selection for udder traits and angularity should improve longevity in the Holstein cattle population. 相似文献
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Impact of conformation traits on functional longevity of Holstein cattle of Iran assessed by a Weibull proportional hazards model 总被引：1，自引：0，他引：1
M. Dadpasand S.R. Miraei-Ashtiani M. Moradi Shahrebabak R. Vaez Torshizi 《Livestock Science》2008,118(3):204-211
A Weibull proportional hazards model was applied to evaluate the effects of 18 linear type traits on the functional length of productive life in Holstein cattle of Iran. Culling data and classification scores on 44,179 cows with first calving from 1996 to 2004 were used. The data included up to 55% of censored records. Length of productive life was defined as the number of days from first calving until last test day or censoring. The significance of each type trait was tested by a likelihood ratio test comparing the full model (with one particular type trait) with reduced models (without any of the type traits). Analyses were performed for each type trait one at a time which included as a covariate in the model. The strongest relationship between length of productive life and type traits were found for fore udder attachment, udder depth, udder cleft angularity and loin strength. Body traits except angularity had minimal effect on functional longevity. Some traits such as udder depth, rear legs side view and foot angle showed an intermediate optimum with respect to longevity and extreme scores of these traits increased risk of involuntary culling. Results of the present study showed that improvement of conformation traits, which is more associated with functional longevity, is a useful way to increase functional length of productive life. 相似文献
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荷斯坦牛体型线性性状与产奶量的相关性研究 总被引：4，自引：2，他引：2
本研究对新疆荷斯坦奶牛的产奶量与体型线性性状进行了相关、通径分析。结果发现，荷斯坦奶牛的乳房纵沟深、后乳房宽、后乳房高与产奶量呈中等正相关；体高、体长、尻宽、尻长与产奶量呈弱相关；后乳房宽、乳房纵沟深是直接影响产奶量的重要性状。 相似文献
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Y. de Haas L.L.G. Janss & H.N. Kadarmideen 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2007,124(1):12-19
This study presents genetic parameters for conformation traits and their genetic and phenotypic correlations with milk production traits and somatic cell score (SCS) in three Swiss dairy cattle breeds. Data on first lactations from Holstein (67 839), Brown Swiss (173 372) and Red & White breeds (53 784) were available. Analysed conformation traits were stature and heart girth (both in cm), and linear scores of body depth, rump width, dairy character or muscularity, and body condition score (only in Holstein). A sire model, with relationships among sires, was used for all breeds and traits and variance components were estimated using AS‐REML. Heritabilities for stature were high (0.6–0.8), and for the linear type traits ranged from 0.3 to 0.5, for all breeds. Genetic correlations with production traits (milk, fat and protein yield) and SCS differed between the dairy breeds. Most markedly, stronger correlations were found between SCS and some conformation traits in Brown Swiss and Red & White, indicating that a focus on a larger and more ‘dairy’ type in these breeds would lead to increased SCS. Another marked difference was that rump width correlated positively with milk yield traits in Holstein and Red & White, but negative in Brown Swiss. Results indicate that conformation traits generally can be used as predictors for various purposes in dairy cattle breeding, but may require specific adaptation for each breed. 相似文献
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选择蚌埠蚂蚁山奶牛场，随机抽取荷斯坦奶牛220头进行6个乳房线性性状即前房附着、后房高度、后房宽度、悬韧带、乳房深度和乳头长度的线性评定和分析。结果表明：蚂蚁山奶牛场荷斯坦奶牛6个乳房性状线性评分分别是30．0分、46．7分、29．5分、38．3分、18．0分和21．0分；功能分各为80分、92分、80分、88分、68分和72分；奶牛乳房线性性状的总体评定成绩中等偏上，前房附着、后房高度、后房宽度、悬韧带、乳房深度、乳头长度的评定等级分别为佳、优、佳、良、中、中；其中以“后房高度”表现最好。 相似文献
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旨在评估宁夏地区荷斯坦牛乳房性状的遗传水平。本研究使用DMU（v6.0）软件的AI-REML模块结合EM算法并配合多性状动物模型对宁夏地区12 415头荷斯坦牛，包括111 735个观察值的9个乳房性状进行遗传参数估计，运用主成分分析法（PCA）探讨构象性状之间的关系。结果表明，宁夏地区荷斯坦牛乳房性状遗传力处于中等偏低水平，乳房深度遗传力值为0.242，乳房质地为0.080，悬韧带为0.183，前乳房附着为0.230，前乳头位置为0.231，前乳头长度为0.173，后乳房高为0.272，后乳房宽为0.378，后乳头位置为0.169。各性状遗传相关范围为-0.277~0.706，表型相关范围为-0.084~0.316。研究共筛选出特征值≥1的4个主成分，占总方差的64.19%，且9个乳房性状在前3个主成分中已全部体现，荷载系数均在0.4以上。本研究通过对宁夏地区奶牛DHI数据的深入挖掘和遗传参数估计，准确地把握了宁夏奶牛群体的结构特征，对于奶牛的选种选配和育种规划具有重要意义。 相似文献