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1.
以雅发褐壳蛋鸡为素材,应用血浆极低密度脂蛋白(VLDL)浓度在零世代和一世代双向选择的基础上,测定二世代蛋鸡高、低脂系40,50及60周龄的血浆VLDL浓度,估计了其遗传参数。结果表明,二世代蛋鸡中后期血浆VLDL浓度随着鸡周龄的增加而增加。同时,各时期血浆VLDL浓度间呈极显著的表型相关(P<0.01)和较高的正遗传相关。各时期高、低脂系血浆VLDL浓度有向两个方向分化的趋势,但同一时期差异不显著(P>0.05),血浆VLDL浓度的遗传力较低。为了扩大选择进展,应采用家系选择为主的方法进行。 相似文献
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以一世代和二世代高、低脂系肉鸡为素材,测定了42,45和49日龄肉鸡血浆极低密度脂蛋白（VLD）浓度和体重,并于二世代时屠宰72只49日龄肉鸡（公、母各半）,测定其肥度性状。结果：血浆VLDL浓度和肥度性状变异大,变异系数分别为34％～60％和21％～27％;血浆VLDL浓度为中等遗传力,因此对血浆VLDL浓度选择宜采用家系和个体选择结合的方法;血浆VLDL浓度和腹脂重（率）呈显著正表型相关,其遗传相关为中等至较高水平;血浆VLDL浓度与体重表型相关很弱,而遗传相关为中等,公、母鸡腹脂重与体重呈显著正表型相关。腹脂率与体重表型相关均不显著。表明对血浆VLDL浓度低向选择,在降低腹脂的同时,体重也将下降。为防止体重的下降,应对血浆VLDL浓度和体重同时进行选择。 相似文献
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本试验以血浆VLDL浓度双向选择的三世代高、低脂系肉鸡作为父系,以商用艾维茵父母代肉鸡为母系,分别组建高脂系×艾维茵(FAV)、低脂系×艾维茵(LAV)两个杂交组合试验群体,于49日龄抽样测定了试验群体的体重、屠体肥度性状和VLDL值,并与艾维茵×艾维茵(AVAV)、高、低脂纯繁系(FF和LL)进行了比较,结果各试验群体肥度性状由高到底的排列顺序为FF＞FAV＞AVAV＞LAV＞LL,反映了经过双向选择后建立的高低脂系的肥度性状在遗传基础上已经分离并能将之稳定遗传,一定程度上证明了双向选择的有效性和实用性. 相似文献
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以父母代肉种鸡为材料，以血浆极低密度脂蛋白（very low density lipoprotein，VLDL）质量浓度为选择指标建立肉鸡高脂系和低脂系，个体测定一世代高、低脂系母鸡产蛋性能、种蛋受精率、孵化率、二世代6周龄体质量，观察血浆VLDL质量浓度选择效应。结果显示，一世代低脂系比高脂系早开产6．7d，低脂系40周龄和54周龄产蛋量显著高于高脂系零世代，一世代低脂系种蛋受精率、受精蛋孵化率、入孵蛋孵化率均优于高脂系；二世代高、低脂系6周龄体质量差异不显著。结果表明，对血浆VLDL质量浓度的低向选择使种鸡产蛋性能、种蛋受精率、孵化率产生了有益的间接反应，但对早期体质量没有影响。 相似文献
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高、低脂系肉鸡肌肉品质的比较 总被引：1，自引：0，他引：1
本文旨在比较分析高、低脂系肉鸡肌肉品质的差异。以东北农业大学培育的高、低脂系第20世代肉鸡为试验动物,采用常规肉品质检测方法,测定肌肉的物理性状、化学性状、组织学特性以及风味物质,并比较这些性状在两系间的差异。结果表明:1)物理性状方面,高脂系肉鸡胸肌的蒸煮损失和滴水损失显著或极显著高于低脂系肉鸡(P0.05或P0.01),而胸肌的肉色亮度值(45 min)和黄度值(45 min和24 h)、pH_(24 h)、失水率和剪切力显著或极显著低于低脂系肉鸡(P0.05或P0.01);高脂系肉鸡腿肌的pH_(24 h)、滴水损失、蒸煮损失和剪切力极显著高于低脂系肉鸡(P0.01),而腿肌的肉色亮度值(45 min)和黄度值(45 min和24 h)、pH_(45 min)和失水率显著或极显著低于低脂系肉鸡(P0.05或P0.01)。2)化学性状方面,高脂系肉鸡胸肌和腿肌的水分和粗蛋白质含量显著或极显著高于低脂系肉鸡(P0.05或P0.01),而粗脂肪含量极显著低于低脂系肉鸡(P0.01)。3)组织学特性方面,高脂系肉鸡胸肌的肌纤维直径显著高于低脂系肉鸡(P0.05),腿肌的肌纤维密度极显著高于低脂系肉鸡(P0.01)。4)风味物质方面,高脂系肉鸡胸肌的甜鲜味氨基酸、必需氨基酸和总氨基酸含量显著或极显著高于低脂系肉鸡(P0.05或P0.01);高脂系肉鸡胸肌和腿肌的多不饱和脂肪酸和必需脂肪酸含量极显著低于低脂系肉鸡(P0.01)。总体而言,高、低脂系肉鸡肌肉的理化性状、组织学特性和风味物质含量差异显著,说明长期对腹脂性状的双向选择会在一定程度上影响肉鸡的肌肉品质。 相似文献
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肉鸡血浆VLDL浓度与肥度性状和体重的相关研究 总被引：1，自引：1，他引：0
以一世代和二世代高、低脂系肉鸡为素材，测定了４２，４５和４９日龄肉鸡血浆极低密度脂蛋白（ＶＬＤＬ）浓度和体重，并于二世代时暑宰７只４９日龄肉鸡（公、母各半）、测定其肥度性状。结果：血浆ＶＬＤＬ浓度和肥度性状变异大，变异系数分别为３４％～６０％和２１％～２７％；血浆ＶＬＤＬ浓度为中等遗传力，因此对血浆ＶＬＤＬ浓度选择宜采用家系和个体选择结合的方法；血浆ＶＬＤＬ浓度和腹脂重（率）呈显著正表型相关，其遗 相似文献
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《黑龙江畜牧兽医》2014,(23)
为了探讨高邮鸭血浆极低密度脂蛋白(VLDL)、总三酰甘油(TG)与体重、体尺性状之间的关系,试验测定了8周龄高邮鸭公母鸭血浆极低密度脂蛋白、TG浓度及体重、体尺性状。结果表明:8周龄高邮鸭公母鸭之间血浆VLDL浓度和TG浓度均差异不显著(P0.05);公鸭胫长、体斜长、半潜水长、胸宽极显著高于母鸭(P0.01),公鸭胫围、龙骨长显著高于母鸭(P0.05),公母鸭体重差异不显著(P0.05);血浆VLDL浓度与体重、胫围、龙骨长及半潜水长呈一定程度的正相关趋势(P0.05);血浆TG浓度与体重、胫围、龙骨长呈一定程度的正相关趋势(P0.05),与胫长、体斜长呈一定程度的负相关趋势(P0.05)。 相似文献
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以父线代肉种鸡为材料,用比浊法测定血浆ＶＬＤＬ浓度,分别以１６周龄,６周龄血浆ＶＬＤＬ浓度为选择指标建立零世代,一世代肉鸡高脂系和低脂系地肉鸡体重和血浆ＶＬＤＬ浓度的选择反应。结果：１．零世代,一世代肉鸡血浆ＶＬＤＬ浓度变异很大,变异系数分别为４３．６％－７４．６％和３８．７％－７９．９％,二个世代选择后,血浆ＶＬＤＬ浓度变异系数在高,低脂质中分别为３７％－５２％和３１％－４６％,表明对血浆ＶＬＤ 相似文献
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对零世代８周龄血浆极低密度脂蛋白（ＶＬＤＬ）浓度进行降低腹脂的间接选择，一世代取得了明显效果：腹脂和肝脂向两极分化，其中肌胃脂和肝脂选择反应较大。低血浆ＶＬＤＬ的选择使腹脂降低，肝脂增加，对产肉性状未产生不利影响。９周龄腹脂率、板油率和肌胃脂率在高ＶＬＤＬ系分别高于低ＶＬＤＬ系２１％，１６％和５１％；肌胃脂率品系间差异极显著（Ｐ＜０．００１）。品系与性别互作对肌胃脂率有明显影响（Ｐ＜０．０５）。腹脂、肌胃脂存在性别差异，腹脂率雌性略高于雄性，而肌胃脂率雄性高于雌性。９周龄肝脂率，高ＶＬＤＬ系显著低于低ＶＬＤＬ系（Ｐ＜０．０１），雌性高于雄性。一世代８周龄血浆ＶＬＤＬ产生了直接选择反应，血浆ＶＬＤＬ浓度，高ＶＬＤＬ系高于低ＶＬＤＬ系。血浆ＶＬＤＬ存在性别差异，雄性高于雌性。一世代高、低ＶＬＤＬ系血浆ＶＬＤＬ和腹脂的变异系数仍然很大，继续对其选择仍然有效。由于血浆ＶＬＤＬ属中等遗传力，并且家系间差异显著，因此，在世代选育中应采取家系结合个体选择法 相似文献
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肉鸡血浆极低密度脂蛋白浓度与屠体肥度性状的相关研究 总被引：8，自引：0，他引：8
以白羽肉仔鸡为研究材料，４９日龄采血，用此法浊法测定血浆极低密度脂蛋白浓度。试验结果表明，血浆ＶＬＤＬ浓度的变异系数为５５％，其与腹脂重，腹脂率呈显著的正表型相关。体重和屠体重与腹膜重呈极显著的正表型相关，对血浆ＶＬＤＬ浓度的低向选择将间接低体重。为防止肉仔鸡上市体重的下降，应该同时考虑对血浆ＶＬＤＬ浓度和体重的选择。对血浆ＶＬＤＬ浓度的低向选择将降低腹膜重，腹脂率，肝脂含量和肝脂重而对胸肌脂肪含 相似文献
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以褐壳蛋鸡祖代母本种鸡为研究材料，用比浊法测定血浆极低密度脂蛋白浓度。试验结果表明，母鸡８１周龄腹脂重，腹脂率，鲜肝脂肪含量的变异系数分别高达４７％，３９％，４７％。表明这些性状在鸡群中未做过选择。血浆ＶＬＤＬ浓度与腹脂重，腹脂度，肝重，肝脂含量均呈正表型相关趋势。 相似文献
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1. Male and female broilers of a pure line were selected over three generations on the basis of high or low plasma very low density lipoprotein (VLDL) concentration at 7 weeks of age. 2. Heritability of plasma VLDL was high (h 2 = 0·50 ± 0·08) and by the third generation mean values in the two lines differed by a factor of 2·5. 3. Correlated responses to selection for low plasma VLDL included a relative decrease in abdominal fat and total body lipid and an increase in body protein, together with improvements in the conversion efficiences of food and dietary protein. 4. There was no difference between the lines in 7‐week body weight. 相似文献
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1. Plasma lipoprotein metabolism and body composition in lines of chicken selected for high- and low-plasma very low density lipoprotein (VLDL) concentrations were compared to the commercial broiler (meat-type) line from which they were derived. 2. Selection for low-plasma VLDL concentration for 10 generations has reduced the rate of VLDL secretion by at least 50% in males whereas selection for high-VLDL concentration has increased the rate of VLDL secretion over 2-fold. 3. Body fat content was highly correlated with rate of secretion of plasma triglyceride-rich (TGR) lipoproteins (r = 0.88 over the three lines). However, extrapolation of the data suggests that birds secreting no TGR-lipoproteins into the plasma would still have substantial amounts of body fat. 4. Selection for high VLDL has increased the proportion of circulating VLDL-triglyceride taken up by the abdominal fat pad by over 2-fold but there was no difference between high- and low-VLDL lines in the proportion of VLDL-triglyceride taken up by tissues and oxidised to [14C]-carbon dioxide. 5. The results confirm the importance of plasma lipoprotein metabolism in determining body composition in the chicken but suggest there are limits to further reduction in body fat content by manipulation of plasma lipoprotein metabolism. 相似文献
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C. C. Whitehead 《British poultry science》1990,31(2):293-305
1. Male and female broilers from a male grandparent line have been selected over 8 generations on the basis of low or high plasma very low density lipoprotein (VLDL) concentration. This has given lines of lean and fat broilers.
2. Plasma VLDL concentration in the two lines has diverged steadily and showed a 7‐fold difference in the 8th generation.
3. Divergence of other traits, including abdominal and total body fat, body protein and conversion efficiencies of food and dietary protein has continued but body weight has not changed with selection.
4. Divergence of body composition and nutrient conversion relative to a commercially selected control line derived from the same origin as the experimental lines has been slightly greater for the fat line.
5. In the lean line, females have been more responsive to selection with the result that body compositions of lean line males and females at 7 weeks have become quite similar.
6. Plasma VLDL concentration decreased little in the lean line over the later generations and showed a lower phenotypic correlation with abdominal fatness than in the fat line in the 8th generation. A limit to selection for body fatness using this criterion may be approaching in the lean, but not in the fat, line. 相似文献
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Contribution of lipoprotein lipase to differences in fatness between broiler and layer-strain chickens 总被引：3，自引：0，他引：3
The growth of abdominal fat in chickens from broiler and layer-strains up to 10 weeks of age was measured and compared with changes in plasma very low density lipoprotein (VLDL) concentration and tissue lipoprotein lipase activities. The growth of abdominal fat in broilers was much more rapid than in layer-strain chickens. Plasma VLDL concentrations in the two strains were similar up to 5 weeks of age but thereafter concentrations tended to be higher in broilers. Plasma VLDL concentrations in both strains were much lower than those necessary for maximum lipoprotein lipase activity. The lipoprotein lipase activity of abdominal fat increased much more rapidly in broilers than in layer-strain chickens. In both strains the pattern of its increase relative to body weight was similar to that of abdominal fat. Differences in the lipoprotein lipase activity of abdominal fat between strains were attributed to differences in both activity/adipocyte and number of adipocytes. They were reduced or abolished if activity was expressed relative to tissue weight, or to its content of DNA or protein. The results strongly suggest that the greater lipoprotein lipase activity of the abdominal fat pad in broilers is an important factor in its rapid growth. 相似文献
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鸡肌内脂肪双向选择对脂肪性状及相关基因mRNA表达的影响 总被引：2，自引：0，他引：2
本试验旨在研究鸡肌内脂肪（IMF）双向选择对脂肪性状及相关基因mRNA表达的影响。试验采用北京油鸡肌内脂肪双向选育系和对照系雏鸡,饲养至56和120 d时,每个系分别屠宰30只母鸡,测定胸肌和腿肌IMF含量、腹脂重、腹脂率及LPL、H-FABP和A-FABP基因mRNA表达量,比较双选系各性状差异,分析IMF遗传选择效果。结果表明,上选系肌肉IMF含量和肉色亮度值（L^＊）显著大于下选系（P〈0.05）,胸肉终pH（pHu）显著低于下选系（P〈0.05）。LPL基因在120日龄上选系腹脂中的mRNA表达量显著高于下选系（P〈0.05）,下选系胸肌中H-FABP基因mRNA的表达显著高于上选系（P〈0.05）。结果表明IMF的双向选择是有效的,该双选系可以作为未来基因定位和基因互作效应研究的宝贵资源群体。 相似文献