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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
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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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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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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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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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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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Genetic trends for fertility,udder health and protein yield in Swedish red cattle estimated with different models 
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下载免费PDF全文 S. Eriksson K. Johansson H. Hansen Axelsson W.F. Fikse 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2017,134(4):308-321
The aim of this study was to estimate and compare genetic trends in Swedish Red cattle using a full multiple-trait (MT) model and trait-group-wise models for female fertility, udder health and protein yield. Field data for maiden heifers from 1989 and cows with a first and second lactation between 1990 and 2007 were included. (Co)variance components were estimated prior to prediction of breeding values. The estimated genetic trends were clearly favourable for protein yield and udder conformation, and in most cases neutral to favourable for clinical mastitis and calving to first insemination. In maiden heifers, the trends were neutral for number of inseminations per service period. Unfavourable genetic trends were estimated for number of inseminations in the first two lactations, but the trends seemed less unfavourable from evaluations within trait groups compared with when using the full MT model. Excluding maiden heifer data affected genetic trends less than using trait-group-wise analyses instead of a full MT model. Unfavourable genetic trends in functional traits may be missed unless the traits are evaluated in a MT model including traits under strong selection. 相似文献
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淮南地区荷斯坦奶牛泌乳系统性状的线性评定及分析 总被引：1，自引：0，他引：1
以安徽淮南乳品公司为试验试点．随机抽取荷斯坦奶牛493头(1～11胎)，进行奶牛体型线性评定中泌乳系统性状即前房附着、后房高度、后房宽度、悬韧带、乳房深度、乳头位置和乳头长度的线性选择评定及分析。结果表明：淮南地区荷斯坦奶牛泌乳系统性状的表现中等偏好．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是31．95、46．98、29，09、37．47、15．08、39．74和20．82分．评定等级各为佳、优、好、良、中、良、中。同时，后房高度、后房宽度、乳头位置的线性评分随胎次变化而变化很小且无规律可循，各胎次几乎相同；乳头长度、悬韧带的线性评分随胎次升高而增加，但后者幅度很小；前房附着、乳房深度的线性评分均表现随胎次的升高而降低的趋势。 相似文献
11.
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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C. D. U. Magnabosco M. Ojala A.
De Los Reyes R. D. Sainz A. Fernandes T. R. Famula 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2002,119(4):221-228
A Derivative Free Restricted Maximum Likelihood (DFREML) algorithm was used with single trait and two traits animal models to estimate the variance and covariance components and thus, heritabilities and phenotypic, genetic and environmental correlations among nine different body measurements and weights of Brahman cattle raised in Mexico. The following measurements were considered: hip width, pin width, hip‐pin width, anterior height, posterior height, body length, thorax perimeter, scrotal circumference and weight. The analysis was based on a total of 1018 animals, born between 1992 and 1995, from 17 herds in the Mexican States of Chiapas, San Luis Potosi, Tabasco, Tamaulipas and Veracruz. The model included the following fixed effects: herd, year‐season of birth, sex, age of the animal and feed management. The only random effect was the direct additive genetic contribution of each animal. All fixed effects in the model were significant for all traits (p < 0.05). Estimated heritabilities for the traits were: hip width 0.57, pin width 0.32, hip‐pin width 0.41, anterior height 0.56, posterior height 0.54, body length 0.32, thorax perimeter 0.49, scrotal circumference 0.02 and weight 0.66. The magnitude of the heritabilities was medium to high, with the exception of scrotal circumference. The genetic correlations among all body measurements were consistently positive and high, ranging from 0.64 to 1.00. Although other measures showed higher genetic correlations with weight, thorax perimeter combines a high value (0.70) with ease and repeatability, making it a useful field measurement to estimate body weight when scales are not available. 相似文献
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E. Gernand D.A. Döhne S. König 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2013,130(6):435-444
Random regression threshold animal models were applied to binary longitudinal claw disorder data for studying genetic parameters of all claw disorders (ACD), as well as to claw disorders divided into different categories: non‐purulent claw disorders (NPCD), purulent claw disorders (PCD), dermatitis digitalis (DD), sole ulcer (SU), phlegmona (PH), laminitis (LAM) and interdigital hyperplasia (IH) in the course of lactation. Claw disorder data were obtained from 26 651 Holstein cows kept in 15 large‐scale contract herds in the region of Thuringia over a period of 5 years from 2007 to 2012. If a cow had one or more entries of the same disorder, for example, sole ulcer, within an interval of 30 days, she was scored with a ‘1’, and otherwise, she received a score of ‘0’ for healthy. Heritabilities for the same disorder were relatively stable between DIM 50 and DIM 300, but they tended to increase in early and late lactation. Highest heritabilities in the range from 0.20 to 0.34 were estimated for IH, and lowest heritabilities were realized for LAM (~ 0.05). Genetic correlations for same traits between different DIMs were high for adjacent test days, but close to zero for distant test days. The relationship between the sire EBVs for claw disorders and official sire EBVs for the type traits ‘foot angle’ was slightly antagonistic with correlation coefficients in the range from 0.05 (DD) to 0.33 (PH). Correlations between lactation EBVs for hock quality, rear leg rear view and the feet and leg index with EBVs for claw disorders were slightly favourable and ranged between ?0.01 (rear leg rear view correlated with SU) and ?0.43 (hock quality correlated with PH). Regarding daily EBVs for claw disorders, the strongest correlation coefficient was of value ?0.46 (LAM early in lactation correlated with the feet and leg index). Genetic parameters from the random regression model were verified by applying a single‐trait repeatability model. Correlation coefficients between lactation EBVs from the random regression model and lactation EBVs from the repeatability model for the same claw disorder were close to 1. Correlations were lower between EBVs from single test days and lactation EBVs from the repeatability models, with a minimal value of 0.58 for PCD measured at day 20. 相似文献
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西门塔尔牛14项线性体型评分的正态分布检验 总被引：1，自引：1，他引：0
１４项线性体型性状引入到包括蒙贝利亚和弗列克维两个类群７０头成年母牛的西门塔尔牛群。体高，强壮度，乳用性，尻宽，前乳房附着，后乳房宽度，乳头位置和乳房静脉８个性状附合正态分布。而后腿侧观，尻宽，后乳房高度，乳房支撑和乳房匀度的评分具有偏崎，乳房深度偏崎十分明显。１３项评分性状是呈陡峰现象，只有乳房静脉一项不是；呈现陡峰现象的原因可能是分值取自于数个评分员的平均值所致。 相似文献
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本研究以1986年中国自主培育兼用牛新品种--三河牛,在内蒙古海拉尔谢尔塔拉种牛场核心群5 257头1998-2012年20 949条繁殖记录为研究材料,以青年牛首次妊娠日龄、青年牛首次产犊日龄、成母牛妊娠期、成母牛空怀期、产犊间隔为研究对象,用SAS 9.13、DMU软件对数据进行处理,采用AI-REML结合EM算法并配合多性状动物模型对各性状影响因素方差组分进行估计,估算出各性状遗传力,并利用各性状育种值分析其遗传趋势.结果显示,青年牛首次妊娠日龄、青年牛首次产犊日龄、成母牛妊娠期、成母牛空怀期、产犊间隔遗传力分别为0.0552、0.0638、0.0527、0.1096、0.0844,繁殖性状除成母牛空怀期遗传力为0.1096外,其余均小于0.1,属于低遗传力性状.青年牛首次妊娠日龄、青年牛首次产犊日龄、成母牛妊娠期、成母牛空怀期、产犊间隔育种值遗传趋势总体上无明显下降趋势,三河牛繁殖性能保持良好.该试验结果为三河牛优化育种方案、提高选种准确性提供重要理论依据. 相似文献
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DONG Gang-hui ZHANG Xu WANG Ya-chun WU Hong-jun LIU Ai-rong ZHANG Yi WANG Dong-sheng CUI Jiu-hui 《中国畜牧兽医》2015,42(6):1547-1552
This study was conducted on 20 949 reproductive records from 1998 to 2012 of 5 257 Sanhe cattle in Xiertala cattle farm,Inner Mongolia,which was a synthetic breed formed in China in 1986.Age at first pregnancy in heifer (AFPH),age at first calving in heifer (AFCH),gestation length in cow (GLC),days open in cow (DOC),and calving interval in cow (CIC) were considered for genetic evaluation.SAS 9.13 and DMU software were used for data processing,and AI-REML combined EM algorithm based on multiple traits animal model was employed for estimating variance components.The heritability for each trait were then calculated,and breeding value was used to analyze the genetic trends.The results showed that the estimated heritabilities of age at first pregnancy in heifer,age at first calving in heifer,gestation length in cow,days open in cow,calving interval in cow were 0.0552,0.0638,0.0527,0.1096 and 0.0844,respectively.The heritabilities were all less than 0.1 except days open (0.1096),indicating these were low inheritable traits.In general,trends of EBVs for each trait didn't show any defined progresses and indicating good reproductive performance maintained in Sanhe cattle.These results lay a theoretical foundation for optimizing breeding programs and improving the accuracy of selection in Sanhe cattle. 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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Breakeven prices for recording of indicator traits to reduce the environmental impact of milk production 下载免费PDF全文
下载免费PDF全文 H. Hansen Axelsson J.R. Thomasen A.C. Sørensen L. Rydhmer M. Kargo K. Johansson W.F. Fikse 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2015,132(1):30-41
A breeding scheme using genomic selection and an indicator trait for environmental impact (EI) was studied to find the most effective recording strategy in terms of annual monetary genetic gain and breakeven price for the recording of indicator traits. The breakeven price shows the investment space for developing a recording system for an indicator trait. The breeding goal consisted of three traits – milk production, functional trait and environmental impact – with economic values of €83, €82 and €?83, respectively. The first scenario included only breeding goal traits and no indicator traits (NoIT). The other scenarios included all three breeding goal traits and one indicator trait (IT) for EI. The indicator traits were recorded on a large scale (stayability after first lactation and stature), medium scale (live weight and greenhouse gases (GHG) measured in the breath of the cow during milking) or small scale (residual feed intake and total enteric methane measured in a respiration chamber). In the scenario with stayability, the genetic gain in EI was over 11% higher than it was in NoIT. The breakeven price of recording stayability was €8 per record. Stayability is easy to record in the national milk recording system, and its use as an indicator trait for EI would not generate any additional recording costs. Therefore, stayability would be a good indicator trait to use to mitigate EI. The highest genetic gain in EI (23% higher compared to NoIT) was achieved when the GHG measured in the breath of the cow was used as indicator trait. The breakeven price for this indicator trait was €29 per record in the reference population. Ideally the recording of a specific indicator trait for EI would take place when: (i) the genetic correlation between the IT and EI is high; and (ii) the number of phenotypic records for the indicator trait is high enough to achieve a moderately high reliability of direct genomic values. 相似文献
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Gerson Antonio Oliveira Júnior Joanir Pereira Eler Johanna Ramírez-Díaz José Bento Sterman Ferraz Mário Luiz Santana Jr. 《Tropical animal health and production》2014,46(6):1031-1036
The objective of this study was to evaluate the impact of including weaning management group (WMG) as an uncorrelated random effect in the genetic evaluation of postweaning traits. Data from 186,507 Nellore animals' sons to 1,734 sires and 75,016 cows were analyzed. Three single-trait models were studied. These models included the contemporary group (CG) as a fixed effect and age of animal at measurement and age of dam at calving as covariates, in addition to the direct additive breeding value as random effect. The CGs for postweaning traits varied between models which included or not WMG as part of the concatenation of fixed effects. In the model in which WMG was not part of the CG, the trait was included as an uncorrelated random effect. The results suggest that although no significant effects were observed on genetic parameter estimates or animal ranking, the inclusion of WMG as an uncorrelated random effect increased the number of observations per CG and contributed to maintaining animals in the analysis that would be discarded because they were in a CG with a small number of observations. This model could therefore be recommended for the genetic evaluation of this Nellore population. 相似文献