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凉山半细毛羊初生到断奶的5个生产性状（羔羊初生重、羔羊断奶重、初生-断奶日增重、断奶毛长度、断奶毛细度）预测成年羊毛（2．5年）的3个生产性状（成年剪毛量、成年毛长度、成年毛细度）,用Matlab6．5软件构建广义回归神经网络预测模型,并通过预测结果和实测结果的统计分析验证本研究所构建的广义回归神经网络预测模型的有效性。预测结果和实测结果的统计分析结果显示该预测模型具有较高的准确性,基于广义回归神经网络构建的预测模型在凉山半细毛羊成年羊毛3个性状上的预测被证明是有效的。 相似文献
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本文根据大柳种羊场1988年126头母羊的周岁鉴定资料,分析了单双羔羊之间的差异性。结果表明,二者在初生重(x_1)、断奶重(x_3)、周岁体重(y_1)、周岁毛长(y_2)和周岁剪毛量(y_3)5个性状之间存在着显著差异;而断奶日龄的差异不显著。进而分析了上述性状之间的相关性,结果显示断奶重与周岁体重以及周岁剪毛量之间有显著相关,为生产实践中以断奶重作为早期选择的主要指标提供了理论基础。 相似文献
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对青海省柴达木地区青海高原毛肉兼用半细毛羊9个主要经济性状进行了遗传力估测。结果表明,初生重、断奶重、周岁剪毛量、羊毛细度、毛长、剪毛前体重、剪毛量都是高遗传力性状,也是青海高原毛肉兼用半细毛羊育种过程中的主要选择依据;断奶重、周岁剪毛量、剪毛前体重与剪毛量之间呈强正遗传相关,断奶重可作为对剪毛量进行早期选择的参数;断奶重与羊毛细度之间呈负遗传相关。 相似文献
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青海细毛羊主要经济性状遗传参数估计 总被引：3，自引：0，他引：3
估测了三角城种羊场青海细毛羊１３个性状的遗传力，表型相关和遗传相关估测结果表明，初生重，断奶重，周岁剪毛量，羊毛细度，毛长，剪毛前体型，剪毛量都是高遗传力性状，通过个体选择可取得良好效果。断奶重，周岁剪毛量，剪毛前体重与剪毛量之间呈强正遗传相关，断奶重可作为早期性状对剪毛量进行早期选择；因断奶重与羊毛细度之间呈负遗传相关，因此要注意细度的变化。 相似文献
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本研究在对山西自然生态条件下影响考力代、夏洛莱及其杂种绵羊的生长、繁殖、剪毛性状的主要系统环境效应进行分析的基础上,对生长性状和产毛性状进行相关分析。通过分析表明,随年龄增大,体尺性状、毛丛长度、剪毛量、剪毛后体重均呈增长趋势(毛丛长度、剪毛量达到一定年龄呈下降趋势);性别对体尺性状、毛丛长度、剪毛量、剪毛后体重均有影响;不同群体,体尺性状、毛丛长度、羔羊初生重均不同;品种因其生产方向不同,各性状也不相同;羔羊出生年份、出生类型对羔羊初生重也有影响。体长、体高和胸围之间有较高的正相关;毛丛长度与体高、胸围、管围,胸围和管围之间均 具有较高正相关;体长与管围呈负相关;剪毛量和剪毛后体重呈较 高的正相关。 相似文献
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青海毛肉兼用半细毛羊生产性能遗传力估测 总被引：1，自引：0，他引：1
通过对青海省柴达木地区青海半细毛羊9个主要生产性能进行,调查研究分析。结果表明：初生重、断奶重、周岁剪毛量、羊毛细度、毛长、剪毛前体重、剪毛量都是高遗传力的生产性能,也是青海半细毛羊育种过程中鉴定选种、组群的主要选择依据;断奶重、周岁剪毛量、剪毛前体重与剪毛量之间呈强正遗传相关,断奶重可作为对剪毛量进行早期选择的生产性能指标;断奶重与羊毛细度之间呈负遗传相关。 相似文献
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本文估测了青海省湖东种羊场细毛羊数量性状中的六个主要表型参数及部分性状间的表型相关，结果表明：青海细毛羊初生重，断奶重，断奶毛长，周岁体重和周岁毛长的变异系数分别为11．33，14．93，17．49，9．25和12．53，变异程度较小，而两周岁剪毛变异系数为27．34％，变异程度较大，初生重与断奶重，初生重与周岁体重，断奶毛长与周岁毛长，断奶重与周岁体重和周岁剪毛率之间的表型相关系数分别咪0．1782，0．2298，0．2724，0．5014和0．4994（P≤0．01）。因此初生重，断奶重与断奶毛长在数量性状的早期选择中可做为辅助选择的参考依据。 相似文献
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兴羔肉羊生长发育规律及遗传评估研究 《畜牧与饲料科学》2022,43(6):72-76
[目的]探究兴羔肉羊的生长发育特征及遗传特性。[方法]对2018—2019年出生的1 054只兴羔肉羊羔羊的初生重、断奶重、6月龄体重、12月龄体重数据进行统计分析,并采集部分羊只6月龄、12月龄、24月龄的体高、体长及胸围数据。详细记录每只羔羊的出生类型及系谱档案,利用WOMBAT软件对其初生重、断奶重进行遗传评估。[结果]兴羔肉羊羔羊初生重和断奶重的遗传力分别为0.980和0.885,表型相关为0.321,遗传相关为0.396;6月龄时,公羊体重占成年体重的44.21%、母羊体重占成年体重的60.33%,公羊和母羊的体尺数据都达到成年体尺数据的80%以上。[结论]兴羔肉羊的初生重和断奶重具有高遗传力,且符合肉用品种羊早期生长发育快的遗传特性。 相似文献
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Estimates of genetic parameters and genetic change for reproduction,weight, and wool characteristics of Columbia sheep 总被引：3，自引：0，他引：3
Genetic parameters from both single-trait and bivariate analyses for prolificacy, weight and wool traits were estimated using REML with animal models for Columbia sheep from data collected from 1950 to 1998 at the U.S. Sheep Experiment Station (USSES), Dubois, ID. Breeding values from both single-trait and seven-trait analyses calculated using the parameters estimated from the single-trait and bivariate analyses were compared with respect to genetic trends. Number of observations were 31,401 for litter size at birth and litter size at weaning, 24,741 for birth weight, 23,903 for weaning weight, 29,572 for fleece weight and fleece grade, and 2,449 for staple length. Direct heritability estimates from single-trait analyses were 0.09 for litter size at birth, 0.06 for litter size at weaning, 0.27 for birth weight, 0.16 for weaning weight, 0.53 for fleece weight, 0.41 for fleece grade, and 0.55 for staple length. Estimate of direct genetic correlation between littersize at birth and weaning was 0.84 and between birth and weaning weights was 0.56. Estimate of genetic correlation between fleece weight and staple length was positive (0.55) but negative between fleece weight and fleece grade (-0.47) and between staple length and fleece grade (-0.70). Estimates of genetic correlations were positive but small between birth weight and litter size traits and moderate and positive between weaning weight and litter size traits. Fleece weight was lowly and negatively correlated with both litter size traits. Fleece grade was lowly and positively correlated with both litter size traits, while staple length was lowly and negatively correlated with the litter size traits. Estimates of correlations between weight traits and fleece weight were positive and low to moderate. Estimates of correlations between weight traits and fleece grade were negative and small. Estimates of correlations between staple length and birth weight (0.05) and weaning weight were small (-0.04). Estimated breeding values averaged by year of birth from both the single-trait and multiple-trait analyses for the prolificacy and weight traits increased over time, but were unchanged for the wool traits. Estimated changes in breeding values over time did not differ substantially for single-trait and multiple-trait analyses, except for traits highly correlated with another trait that was responding to selection. 相似文献
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Estimates of genetic parameters and genetic change for reproduction,weight, and wool characteristics of Targhee sheep 总被引：2，自引：0，他引：2
Genetic parameters from both single-trait and bivariate analyses for prolificacy, weight, and wool traits were estimated using REML with animal models for Targhee sheep from data collected from 1950 to 1998 at the U.S. Sheep Experiment Station, Dubois, ID. Breeding values from both single-trait and seven-trait analyses calculated with the parameters estimated from the single-trait and bivariate analyses were compared across years of birth with respect to genetic trends. The numbers of observations were 38,625 for litter size at birth and litter size at weaning, 33,994 for birth weight, 32,715 for weaning weight, 36,807 for fleece weight and fleece grade, and 3,341 for staple length. Direct heritability estimates from single-trait analyses were 0.10 for litter size at birth, 0.07 for litter size at weaning, 0.25 for birth weight, 0.22 for weaning weight, 0.54 for fleece weight, 0.41 for fleece grade, and 0.65 for staple length. Estimate of direct genetic correlation between litter size at birth and weaning was 0.77 and between birth and weaning weights was 0.52. The estimate of genetic correlation between fleece weight and staple length was positive (0.54), but was negative between fleece weight and fleece grade (-0.47) and between staple length and fleece grade (-0.69). Estimates of genetic correlations were near zero between birth weight and litter size traits and small and positive between weaning weight and litter size traits. Fleece weight was slightly and negatively correlated with both litter size traits. Fleece grade was slightly and positively correlated with both litter size traits. Estimates of correlations between staple length and litter size at birth (-0.14) and litter size at weaning (0.05) were small. Estimates of correlations between weight traits and fleece weight were positive and low to moderate. Estimates of correlations between weight traits and fleece grade were negative and small, whereas estimates between weight traits and staple length were positive and small. Estimated breeding values averaged by year of birth from both the single- and seven-trait analyses for the prolificacy and weight traits increased over time, whereas those for fleece weight decreased slightly and those for the other wool traits were unchanged. Estimated changes in breeding values over time did not differ substantially for the single-trait and seven-trait analyses, except for traits highly correlated with another trait that was responding to selection. 相似文献
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Genetic parameters among weight, prolificacy, and wool traits of Columbia, Polypay, Rambouillet, and Targhee sheep 总被引：2，自引：0，他引：2
Genetic parameters for Columbia, Polypay, Rambouillet, and Targhee sheep were estimated using REML with animal models for prolificacy, weight, and wool traits. All bivariate analyses included a covariance between additive genetic effects for the two traits plus appropriate additional covariances. Number of observations by breed ranged from 5,140 to 7,095 for prolificacy traits, from 7,750 to 9,530 for weight traits, and from 4,603 to 34,746 for wool traits. Heritability estimates ranged from .03 to .11 for prolificacy traits (litter size at birth and litter size at weaning), from .09 to .26 for weight traits (birth weight and average daily gain), and from .25 to .53 for wool traits (fleece weight, fleece grade and staple length). Estimates of direct genetic correlations among prolificacy and among weight traits were positive and ranged from .58 to 1.00 and .18 to 1.00, respectively. Estimates of direct genetic correlation between fleece weight and staple length were positive (.50 to .70) but were negative between fleece weight and fleece grade (-.60 to -.34) and between staple length and fleece grade (-.72 and -.40). Prolificacy and wool traits were essentially uncorrelated. Weight and prolificacy traits were slightly positively correlated. Weight traits had a moderate positive direct genetic correlation with fleece weight and staple length, but were uncorrelated with fleece grade. These estimates of genetic parameters between prolificacy, weight, and wool traits can be used to construct multiple-trait selection indexes for dual-purpose sheep. 相似文献
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利用19只公羊和5群母羊来测定初生、断奶和周岁时的杂交优势水平。公羊的基因型包括:纯种新疆细毛羊(XX)、纯种澳州美利奴(AA)和它们的一代杂种(F_1):母羊的基因型只有两个,即(XX)和(F_1)。试验于1987—1989年在新疆维吾尔自治区南山种羊场进行,试验设计了一个不同基因型之间的随机交配,以便估计性状的遗传参数和杂交优势水平。 用计算机分析了552个后代的记录。初生重、断奶重、周岁体重、断奶毛长、周岁毛长和周岁剪毛量的杂交优势分别是4.0％、2％、11.55％、0.4％、6.05％和3.49％。生长发育性状的杂交优势水平明显地高于羊毛生长性状的杂交优势水平。 相似文献
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为探索非遗传因素对中国美利奴羊（新疆型）主要经济性状的影响,试验对拜城种羊场1992-2010年共19年周岁母羊鉴定记录进行统计分析,利用最小二乘方差分析法研究出生年份、群别及出生月份3个非遗传因素对周岁母羊鉴定记录的6个主观鉴定性状（头毛评分、毛密度评分、毛弯曲评分、毛细度评分、体型外貌评分、品种等级评分）和4个客观测定性状（毛长度、鉴定时体重、剪毛后体重、剪毛量）共10个经济性状的影响。结果表明,出生年份和群别对10个性状均有极显著影响（P<0.01）;出生月份对除毛密度评分、毛细度评分、品种等级评分外的其他7个性状均有极显著影响（P<0.01）。从毛细度、毛长度和剪毛量3个最主要的性状来看,2008年毛细度评分最高,显著高于2006、2007和2010年（P<0.05）;1996年毛长度最长,显著高于1994、2002、2004、2006、2007、2008和2010年（P<0.05）,与1995、2003和2009年差异不显著（P>0.05）;1995年剪毛量最多,显著高于1994和2009年（P<0.05）,与1992年差异不显著（P>0.05）;除此之外,其他年份的毛细度评分、毛长度和剪毛量均极显著低于最高值（P<0.01）。除2号群外,不同群别各有优势。1、2月份出生的羊较3、4月份好。由此可见,出生年份、群别和出生月份非遗传因素对中国美利奴羊（新疆型）的主要经济性状存在显著影响,因此,在遗传参数估计和遗传评定时应该综合考虑这些因素,从而为获得更为全面、准确的育种值及制定育种方案提供参考依据。 相似文献
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运用动物模型BLUP法时敖汉细毛羊的早期性状和产毛性状进行分析得出:模型(1)适合估计周岁重、断乳毛长度和断乳毛细度;模型(4)适合估计初生重和断乳重;模型(5)适合估计产毛量、体重和毛长度;模型(7)适合估计毛细度、毛弯曲分、毛密度分和毛油汗分. 相似文献