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采血应激对蛋鸭产蛋性能影响的研究 总被引：3，自引：0，他引：3
为了研究采血应激对蛋鸭产蛋性能的影响程度，本文测定了金定鸭和莆田黑鸭采血前后各10天的产蛋量、蛋重和产蛋率，并用t-检验进行差异性分析。发现采血应激使金定鸭产蛋量下降，（P〈0．05）；蛋重减轻（P〈0．05）；产蛋率下降（P〈0．05）。采血应激使莆田黑鸭产蛋量下降（P〈0．05），但采血后蛋重减轻不明显，（P〉0．05）。 相似文献
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采用多性状动物模型BLUP和非求导约束最大似然法（MTDFREML）估计了引进罗曼蛋鸡纯系配套组合中4个品系9个性状的方差组分和遗传参数,并估计了固定效应的BLUE值和动物个体的加性遗传效应值（育种值）,分析了测定性状的世代间遗传趋势和表型趋势。结果表明,4个系各性状的遗传力基本一致,体重、蛋重以及不同周期的产蛋量之间存在显著的正相关。蛋重与产蛋量存在较强的遗传负相关。六个世代选育后,各品系蛋重、产蛋量的平均育种值均有提高,表明对产蛋量和蛋重的选择是有效的。 相似文献
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采用多性状动物模型BLUP和非求导约束最大似然法（MTDFREML）估计了引进罗曼蛋鸡纯系配套组合中4个品系9个性状的方差组分和遗传参数,并估计了固定效应的BLUE值和动物个体的加性遗传效应值（育种值）,分析了测定性状的世代间遗传趋势和表型趋势。结果表明,4个系各性状的遗传力基本一致,体重、蛋重以及不同周期的产蛋量之间存在显著的正相关。蛋重与产蛋量存在较强的遗传负相关。六个世代选育后,各品系蛋重、产蛋量的平均育种值均有提高,表明对产蛋量和蛋重的选择是有效的。 相似文献
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采用山麻鸭高产系与绍鸭青壳系，通过正交、反交等试验，测试其生长发育、产蛋性能、饲料报酬等生产水平，得出绍×山杂交鸭300～500日龄体重1．51—1．54kg，开产日龄124d，500日龄产蛋量达309．32枚，产蛋重21．02kg，料蛋比3．16：1。绍×山杂交鸭500日龄产蛋量、产蛋重、料蛋比比山麻鸭高产系提高1．89％、2．28％和0．32％，比绍鸭青壳系提高8．88％、8．12％和7．6％，杂种优势力分别达到5．02％、5．09％和4．09％，杂种优势显著。山×绍组合500日龄产蛋量300．08枚、产蛋重20．50kg、料蛋比3．3：1，与亲本山麻鸭高产系比差异不显著（P〉0．05）。 相似文献
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肉用北京种鸭产蛋期的饲养管理，主要是以提高种鸭的产蛋量，受精率，蛋重，减少破损蛋，节省饲料，降低死亡率和淘汰率为目的。肉用北京种鸭产蛋期的饲养管理，主要是以提高种鸭的产蛋量、受精率、蛋重、减少破损蛋、节省饲料、降低死亡率和淘汰率为目的。为实现上述任务，现将北京肉用种鸭在产蛋期的饲养管理技术介绍如下： 相似文献
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麻阳白鹅数量性状的遗传方差估计与产蛋量选择 总被引：2，自引：0，他引：2
利用最小方差二次无偏估计（ＭＩＶＱＵＥ）法计算了麻阳白鹅三个产蛋性状和二个体重性状的遗传力，结果表明，开产日龄、蛋重、成年体重为中等到高遗传力性状（０．３６—０．６４），初生重的遗传力较低（０．１６），产蛋量的遗传力估值（０．３４—０．４０）高于有关报道。相关系数估计的结果表明上选第一生物年产蛋量对于后继年度产蛋量的改良可能不会产生显著效果。 相似文献
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单冠变异与鸡产蛋性能关系的研究 总被引：1，自引：0，他引：1
利用新扬州鸡探讨了单冠变异－冠尖数目变异，冠的大小变异，冠直立和倒向一侧的变异，对产蛋量，蛋重，开产日龄，开产体重的影响。结果表明，单冠侧向一侧母鸡的开产日龄显著早于单冠直立的母鸡，单冠冠尖数为４、５、６的母鸡比冠尖数为３的母鸡有显著或极显著大的蛋重和较高的产蛋量，冠厚与产蛋量呈极显著的负的表型相关（ｒ为－０．３２）。冠高与开产体重显著的正的表型相关（ｒ为０．１９８），冠长与开产日龄，开产体重，产 相似文献
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通过分析丝羽乌骨鸡白羽母系(BM)选育第六、七世代开产后20周内周平均产蛋量、300日龄产蛋量(EGN)、开产日龄(AFE)、开产体重(BWT)、开产蛋重(EWT),描绘两世代产蛋曲线300日龄产蛋量、开产日龄、开产体重、开产蛋重之间相关分析和两世代产蛋性能的均数差异显著性检验.结果表明,开产日龄与300日龄产蛋量成负相关(-0.00456),开产体重与300日龄产蛋量成正相关(0.00244),开产体重与开产蛋重成正相关(0.21078),开产蛋重与300日龄产蛋量成负相关(-0.10614),开产蛋重与开产日龄成正相关(0.32942),两世代产蛋性能有显著差异. 相似文献
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蛋鸡产蛋量遗传规律及对育种选择的启示 总被引：7，自引：1，他引：6
产蛋量性状的遗传力随产蛋周龄的增加表现出前高中低后回升的变化趋势。不同定义的遗传力其遗传规律及生物学意义也不同。前期产蛋量与６０周龄产蛋量的遗传相关随周龄增大而增大，一般在３６—４０周龄后均具有育种意义。３６周龄的体重和蛋重与总蛋重间为强正遗传相关。从选择效率来看，选择总蛋重比选择产蛋数更为有利 相似文献
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为研究麻旺鸭产蛋性状、体尺性状对蛋重的影响,对89只成年麻旺鸭蛋壳重、纵径、横径和体重、体尺性状与蛋重的相关性进行分析。结果表明,麻旺鸭蛋重与蛋壳重、纵径、横径、体重极显著相关（P〈0．01）,相关系数分别为0．654、0．556、0．95、0．654。蛋的横径对蛋重的直接影响达到极显著水平,通径系数为0．8221,纵径对蛋重的直接影响达到显著水平,通径系数为0．1973。蛋的横径对蛋重的决定程度为67．59％,体重对蛋重的决定程度为24．99／5。研究结果提示,可以利用蛋的横径辅之体重进行蛋重的选择。 相似文献
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Heritabilities and genetic correlations of laying performance in Muscovy ducks selected in Taiwan 总被引：1，自引：0，他引：1
1. Genetic parameters in the base population of a closed experimental strain of Muscovy ducks, selected for body weight at 10 weeks of age, were estimated from data in 8 successive generations, for the following traits: age at first egg (AGE1EGG), total number of eggs laid at 40 and 52 weeks of age (NEGG40 and NEGG52), number of eggs laid during 15 and 22 weeks in the first laying cycle (NEGG15W and NEGG22W), and their Box-Cox transformed data. 2. The method of multi-trait restricted maximum likelihood with an animal model was used to estimate genetic parameters. Only the results obtained with non-transformed data are shown. 3. Heritability estimates for laying performance showed moderate values, increasing little with age: 0.20+/-0.03 (AGE1EGG), 0.23+/-0.03 (NEGG40), 0.27+/-0.03 (NEGG52), 0.20+/-0.03 (NEGG15W), and 0.22+/-0.03 (NEGG22W). 4. Genetic correlations between laying traits were high. Genetic correlation between AGE1EGG and egg number was negative, it was positive between total numbers of eggs at 40 and 52 weeks and egg numbers in the first laying cycle. 5. Body weight at 10 weeks of age exhibited positive genetic correlations (0.46+/-0.06) with age at first egg and negative with egg production traits (-0.28+/-0.06 to -0.41+/-0.06). 6. The cumulated predicted genetic gains, after 7 generations of selection, expressed per genetic standard deviation unit (sigma(g)) were 0.06 sigma(g), 0.07 sigma(g), 0.17 sigma(g), 0.23 sigma(g), and 0.25 sigma(g) for AGE1EGG, NEGG40, NEGG52, NEGG15W, and NEGG22W, respectively. 7. Selecting Muscovy ducks to improve laying in Taiwanese climatic conditions would be possible using the number of eggs laid up to 52 weeks of age as the selection criterion. Because unintended selection effects for laying traits were present, the selection experiment for body weight at 10 weeks of age was not antagonistic with laying traits. 相似文献
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1. The objective of this study was to investigate the strength of the genetic association between growth and reproduction traits in turkeys selected for body weight, conformation and egg production. 2. Two distinct populations but derived from the same heavy turkey female line and situated in different locations (UK and USA), were used to estimate genetic parameters using multivariate REML for the following traits: body weight at 14 (BW14), 19 (BW19) and 24 (BW24) weeks of age and total egg number (EGG). 3. A Box-Cox transformation was applied to egg production data to reduce the impact of non-normality. 4. The heritability estimates for each trait for the UK and USA populations, respectively, were: BW14 0.37 and 0.48; BW19 0.34 and 0.43; BW24 0.28 and 0.43; EGG 0.22 and 0.34. 5. The genetic correlation between the body weight at all ages and the total egg production was strongly negative, reaching a value of -0.75 for the UK and -0.55 for the USA population. 6. The comparison of our results with published estimates in turkeys suggests that the genetic correlation may get stronger in magnitude following selection for increased body weight. 7. This could arise from fixation during selection of genes favouring larger weights but with minimal effect on egg production, leaving the segregating genetic variation dominated by pleiotropic loci with antagonistic effects on the traits. 8. Thus, in order to avoid continued selection for body weight reducing egg production to a point where natural selection offsets selection gains, alternative selection strategies should be considered. 相似文献
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Effect of daidzein on egg-laying performance in Shaoxing duck breeders during different stages of the egg production cycle 总被引：1，自引：0，他引：1
The effect of a phyto-oestrogen, daidzein, on the laying performance of Shaoxing female ducks was examined in three experiments performed at different stages of the egg production cycle. Egg-laying rate, egg weight, egg composition, feed conversion ratio, hatchability characteristics of eggs and body weight, ovary and oviduct weight, as well as changes in serum concentrations of T3, T4 and E2 were recorded as response criteria. In the first experiment, 68 young ducks, 100 d of age, were given a basal diet (maize-soybean meal) with or without 3 mg of daidzein/kg diet for 42 d. Daidzein did not affect the onset of lay but apparently decreased egg-laying rate and mean egg weight as well as the feed conversion ratio. In the second experiment, 240 breeding ducks, 402 d of age, were allotted at random to three groups and given the basal diet containing daidzein at 0 (control), 3 (Da1) and 5mg/kg (Da2) for 35d. Egg-laying rate, mean egg weight and feed conversion ratio increased in both Da1 and Da2 groups. However, an adverse effect of daidzein on fertility and hatchability was observed. In the third experiment, 320 breeding ducks, 415 d of age, were fed on the basal diet with or without 5mg of daidzein/kg diet for 63 d. Egg-laying rate increased by 7.7%, average egg weight tended to increase, whereas yolk/albumen ratio decreased. Daidzein-treated ducks had higher body weight and oviduct weight compared with their controls. Elevated plasma T4 and E2 concentrations accompanied these phenotypic changes, but serum T3 was not affected. It is suggested that daidzein exerts divergent effects on the egg-laying performance of Shaoxing ducks under different physiological conditions and this action is dose-dependent. The changes in circulating E2 imply possible participation of endogenous oestrogen in the mechanism of daidzein action. 相似文献
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本实验旨在探讨绍兴鸭剩余采食量(RFI)与生产性能及蛋品质之间的关系。测定300只绍兴鸭410~470日龄的采食量、体重、平均蛋重、蛋品质,计算出剩余采食量与料蛋比,并分析剩余采食量与生产性能及蛋品质的相关性。结果显示:绍兴鸭平均采食量、平均蛋重、体重、体增重、料蛋比、剩余采食量分别为198.8 g/d、73.0 g、1500.9 g、2.5 g/d、2.7、3.5 g/d;低剩余采食量组的剩余采食量、采食量以及料蛋比极显著低于高剩余采食量组;相关性分析表明,剩余采食量与采食量和料蛋比呈极显著正相关(P<0.01);采食量与平均蛋重、体重呈极显著正相关(P<0.01),与料蛋比呈极显著负相关(P<0.01),与体增重呈显著正相关性(P<0.05);蛋品质分析结果表明,高剩余采食量组仅蛋黄色泽水平显著高于低剩余采食量组;相关性分析表明,剩余采食量与蛋品质各指标间均无显著相关性。本试验结果表明,以剩余采食量为蛋鸭选育指标是可行的,且选育低剩余采食量的鸭子能显著降低采食量,提高饲料效率,且不改变产蛋重及蛋品质。 相似文献
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利用PCR—RFLP技术对高邮鸭催乳素（Prolactin，PRL）基因内含子1进行了SNP检测和测序分析，并对该基因与高邮鸭产蛋性状的相关性进行了研究。结果表明：PRL基因内含子1存在两个Dra Ⅰ酶切位点，其中1个位点具有DraⅠ多态性。该位点由于在1326位点发生了T→C的碱基突变，产生了AA、AB和BB3种基因型。基因型BB和等位基因B的频率最高；BB基因型个体30周龄蛋重极显著高于AB基因型个体（P〈0．01）；AB基因型个体的双黄率显著高于BB基因型个体（P〈0．05）；3种基因型间产蛋数、最长连产天数和开产体重无显著差异。 相似文献
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【目的】 试验旨在研究鸭产生螺纹蛋程度的遗传力及其与蛋品质相关性状的遗传相关性。【方法】 选择A系母鸭600只，收集产蛋期所产种蛋，并根据螺纹在鸭蛋表面的覆盖面积，将螺纹等级划分为0、1、2、3、4级。观察测定产生螺纹蛋的等级和其他蛋品质相关性状，使用限制性最大似然估计法并结合线性混合模型进行遗传力及相关性状遗传参数估计。【结果】 试验期间，600只母鸭中有418只母鸭产蛋，共收集到1 171枚种蛋，其中，0、1、2、3和4级螺纹蛋分别有742、135、161、93和40枚，分别占总数的63%、12%、14%、8%和3%；产生0、1、2、3和4级螺纹蛋母鸭分别为228、55、69、46和20只；螺纹蛋等级、平均蛋重、平均蛋型指数和开产体重的遗传力分别为0.30、0.29、0.52和0.72，属于较高遗传力，产蛋总数的遗传力为0.15，为中等遗传力。螺纹蛋等级与产蛋总数具有较高的遗传正相关（0.34）和较低的表型正相关（0.12）。【结论】 螺纹蛋等级、平均蛋重、平均蛋型指数和开产体重均具有较高的遗传力，对某些产生螺纹蛋等级较高的母鸭进行选择淘汰，可以降低鸭产生螺纹蛋的比例。本研究对鸭产生螺纹蛋的等级进行划分，可以精确的区分螺纹蛋之间的差别，为后续的相关研究提供分类标准，为产蛋性能的遗传改良提供依据和参考。 相似文献
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1. The performance of indigenous ducks (ID), Khaki Campbell (KC) and their reciprocal crossbred layers was studied from 19 to 58 weeks of age. For each genotype, 4 x 18 ducks (3 males + 15 females) were reared under a semi-intensive system (SIS) and an intensive system (IS) with standard management, and 4 x 50 ducks (8 males + 42 females) were reared in an extensive system (ES) with traditional management. 2. In comparison to KC, ID were superior in terms of age at first egg, age at 50% egg production, egg weight, hatchability, eggshell thickness with higher egg shape index. KC ducks were superior to ID in body weight, egg production and feed/kg eggs. Egg quality was similar among the genotypes. Crosses were superior to their parent breeds in age at first egg, egg production and feed/kg eggs. They were also superior to KC in egg weight and egg-shell thickness with a higher egg shape index. 3. The performance of genotypes in the SIS and the IS was similar and superior to the ES except for fertility and yolk colour. 4. Significant heterotic effects were recorded for age at first egg, age at 50% egg production, egg production per duck-day, feed efficiency and egg weight in crosses. Performance was similar in the reciprocal crosses, but superior to their parent breeds. 相似文献