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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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西门塔尔牛奶产量与其体型线性性状的相关,通径分析 总被引：4，自引：0，他引：4
本文通过对某牛场２０头西门塔尔牛产奶量与其体型线性性状进行相关、通径分析,结果表明：尻长、乳房深、体高、胸围、乳头长与其产奶量呈弱正相关,尻长、尻宽、乳头是影响产奶量的重要性状,且是正向作用;体高、胸围是影响产奶量的重要性状,起负面作用;尻长、尻宽对产奶量的直接作用大。 相似文献
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奶牛难产度与其体型线性性状的相关,通径分析 总被引：2，自引：1，他引：1
本文通过对双桥农场２６２头荷斯坦奶牛难产度与其体型线性性状进行相关，通径分析，结果表明：乳房深与难产度呈正相关，且是影响奶牛难产度的主要性状之一，胸围，尻长，尻宽与难产度呈负相关，且间接起负面影响，体深也是影响奶牛难产度的主要性状。 相似文献
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本文利用北京市双桥农场的成乳牛体型鉴定资料，对１６个体型性状和由它们计算出的体型整体评分进行了通径分析。结果表明，应用乳房悬垂、前房附着、后肢侧视、体强度来直接选择体型整体评分将是有效的；应用乳后视、乳房深度、后房宽度、前房附着、尻角度、蹄角度、体高来间接选择整体评分将是有效的。本文计算了１６个体型性状对体型整体评分不数。结果表明，乳房悬垂、前房附着、后肢侧视、体强度的直接决定系数值最大。 相似文献
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奶牛体型线性性状与其成年奶当量相关与通径分析 总被引：3，自引：0，他引：3
本文对1990—1991年度双桥农场3个奶牛场603头荷斯坦奶牛体型线性性状评分与其成年奶当量进行了相关通径分析，数据采用dBASE Ⅱ进行管理，应用Turo-Basic编程在AST-286进行计算分析。分析表明：奶牛体型线性性状中，乳房深与成年奶当量呈较强负相关r=-0．4266；尻宽与产奶量呈正相关(r=0．2939)；这二者是影响成年奶当量的主要性状。 相似文献
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对甘肃临泽雪莲乳品有限责任公司的奶牛群进行体型线性评定,旨在明确不同胎次奶牛的体型差别,正确评估该牛群质量,不断提高高产奶牛比例,为生产管理及遗传改良提供依据.选择160头1～5胎奶牛,采用50分制奶牛体型线性评定方法,比较不同胎次间各性状测定值及功能分的变化,分析各胎次及全群奶牛的特征性状评分和整体评分差异.胎次对奶牛体高、尻角度和尻宽的测定值及功能分有显著影响(P<0.05).1～4胎内体高、尻角度及尻宽测定值随胎次有增加的趋势:2～5胎牛体高功能分优于第1胎,1～3胎牛尻角度功能分优于第4～5胎,1～4胎牛尻宽的功能分随胎次增加表现更加良好.全群奶牛平均整体评分81分,等级为"佳",体型表现较理想;2～3胎牛的整体评分及四项特征分表现最好;体高、胸宽、体深及尻角度线性分达最佳分段,体躯容积特征性状评分表现优异,但所有极端性状及一般外貌特征性状表现相对较差.不同胎次奶牛在单个性状及特征性状评分方面有一定差异,表明该牛群今后选育中应注重对产奶量影响较大的极端性状、特征性状及整体评分的平衡选择,并提高一般外貌的表现水平. 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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Reproductive data collected from 13 medium‐size goat farms in central Mexico (582 goats), were used to investigate if linear type traits influenced reproductive performance of high‐yielding dairy goats. Data were analysed using multiple stepwise forward logistic regressions. Goats with the higher scores for strength were 1.43 times more likely (p < 0.05) to have larger litters (1.49 vs 1.39) than goats with lower strength. Goats approaching level rump angles were 1.68 times more likely (p < 0.01) to have larger litters, compared with goats with extremely sloped rump angles (1.48 vs 1.37). Goats with rear legs nearly straight (posty) in hock tended (p < 0.08) to presented larger litters than goats with rear legs slightly angled (sickled) in hock (1.49 vs 1.38). Less pronounced rump angle was favourable associated (p < 0.05) with litter weight (4.88 vs 4.53 kg) compared with goats with low pin bones. Goats with poorer udder texture were 1.42 more likely (p < 0.05) to have heavier litters than goats with good udder texture. Goats with faulty mammary system tended (p < 0.07) to have heavier litters than goats with good mammary system. Increasing udder height was associated (p < 0.05) with increasing number of services per conception. Goats with good fore udder attachment and non‐refined heads were at reduced risk (p < 0.05) for stillbirths. Goats with stronger median ligament were 65% less likely (p < 0.05) to lose their foetuses than those with looser udder support. Our findings indicate that a greater litter size and litter weight is expected in goats as rump angle becomes less sloped. This study showed that a relationship exists between strength of goats and litter size, and that some traits linked to high milk yield were antagonist to some reproductive traits. 相似文献
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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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随机抽取荷斯坦奶牛 472头 (1～ 11胎 )进行奶牛隐性乳房炎的检测 ,乳用特征性状 (楞角性、尻宽、尻角度、后肢侧视、蹄角度 )的线性评定 ,以及隐性乳房炎与乳用特征的相关性分析。结果表明 :奶牛隐性乳房炎的乳区阳性率与楞角性、尻宽、尻角度、后肢侧视、蹄角度的相关系数分别为 0 1171、0 10 3 0、0 0 681、0 0 180、-0 12 65 ,其中与楞角性、尻宽分别达到显著水平 (P <0 0 5 )的正相关 ,与蹄角度达极显著 (P <0 0 1)的负相关。奶牛阳性率与楞角性、尻宽、尻角度、后肢侧视、蹄角度的相关系数分别为 0 0 967、0 0 5 61、0 0 2 82、0 0 12 7和 -0 0 670 ,其中除与楞角性为显著水平 (P <0 0 5 )的正相关 (0 0 967)外 ,其余均不显著 (P >0 0 5 )。 相似文献
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奶牛乳房性状与产奶量及排乳性能的关系 总被引：1，自引：0，他引：1
选择胎次相同,泌乳月份相近的经产荷斯坦牛197头,分别测定其后乳房宽度,后乳房深度,后乳房高度,乳房纵沟深,乳头直径,乳头长度等6个高遗传力性状,并与排乳性能及产奶量的相关性进行研究.结果表明:奶牛乳房纵沟深,乳头直径,乳头长度等6个高遗传力性状,并与排乳性能及产奶量的相关性进行研究.结果表明:奶牛乳房纵沟深、后乳房宽度、乳头长、乳头直径与排乳速度有极显著正相关(P＜0.01),后乳房高度与排乳速度呈现中等正相关(P＜0.05),平均排乳时间与后乳房宽度呈现显著正相关(P＜0.05);日产乳量与乳头长度呈中等负相关(P＜0.05),与乳房纵沟深、乳头直径呈显著正相关(P＜0.05),305 d产乳量与乳房纵沟深、后乳房宽度呈极显著强正相关(P＜0.01),与乳头直径呈显著正相关(P＞0.05),与乳头长度有极显著负相关(P＜0.01). 相似文献
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选择安徽淮南乳品公司为试验试点,随机抽取荷斯坦奶牛472头(1~≥6胎)进行隐性乳房炎与乳房性状相关性分析,测定的乳房性状主要包括前房附着、后房高度、后房宽度、悬韧带、乳房深度、乳头位置和乳头长度。结果表明:淮南地区荷斯坦奶牛隐性乳房炎的乳区阳性率和奶牛阳性率分别为25.79%和53.18%;乳房性状前房附着、后房高度、后房宽度、悬韧带、乳房深度、乳头位置、乳头长度的线性评分分别为31.92分、47.02分、29.00分、37.64分、20.02分、39.74分、20.88分。隐性乳房炎的乳区阳性率与前房附着、后房高度、后房宽度、悬韧带、乳房深度、乳头位置、乳头长度的表型相关系数分别是-0.0731、0.0211、0.1003、-0.0369、0.0996、-0.0323及-0.0151,其中与后房宽度、乳房深度为显著(P<0.05)的正相关,其余均未达到显著水平(P>0.05);奶牛阳性率与前房附着、后房高度、后房宽度、悬韧带、乳房深度、乳头位置、乳头长度的表型相关系数分别为-0.0427、0.0680、0.0347-、0.0060、0.1071、-0.0119和0.0223,除与乳房深度为显著(P<0.05)的正相关外其余均不显著(P>0.05)。 相似文献
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奶牛外貌评分与产奶量相关性研究 总被引：1，自引：0，他引：1
某奶牛场随机取30头奶牛,测定其305d产奶量及10个体型外貌评分性状,计算产奶量与体型性状之间的相关系数,求得产奶量的各自通径系数,研究奶牛10个体型性状与生产效率性状之间的关系。结果表明,整体评分与305d产奶量之间存在弱正相关（P〉0．05）;10个评分性状中,后乳房高度和宽度与305d产奶量呈极显著相关（P〈0．01）。乳房中隔和乳房深度与305d产奶量呈显著相关（P〈0．05）。整体外貌评分、后乳房宽度、乳房中隔越高则产奶量也越高,后乳房高度和乳房中隔是对产奶量起主要作用的性状。 相似文献
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H. Uribe L. R. Schaeffer J. Jamrozik T. J. Lawlor 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2000,117(4):247-259
Random regression models were applied to eight conformation traits (i.e. stature, rump angle, thurl width, rear leg set, rear udder width, rear udder height, udder depth, and fore udder attachment) of Holstein cows from the northeastern United States. Covariates for fixed and random regressions included age and age‐squared for six of the traits, and two additional covariates were included for rear udder width and rear udder height. Other effects in the model were herd—year‐classifier and months in milk. Fixed covariates were nested within year of birth of the cow. Variance components were estimated using Bayesian theory and Gibbs sampling procedure. Estimated breeding values from the random regression models were compared to two single trait models. The first model utilized only the first classification record of the cow in first lactation, and the second model utilized all classifications of the cow in a simple repeatability model. Additive genetic merit for conformation traits changed with the age of the animal. Some traits were affected by age more than others. The single trait, single record model and the simple repeatability model were not appropriate in predicting breeding values at mature ages for rear udder width and rear udder height. 相似文献