血浆VLDL浓度双向选择对蛋鸡生产性能的影响

以雅发褐壳蛋鸡为供试材料 ,在零世代和一世代双向选择的基础上 ,应用血浆极低密度脂蛋白(VLDL)浓度对体腹脂性状继续进行双向选择 ,比较了高低脂系的生产性能 ,并研究了二世代母鸡中后期血浆VLDL浓度与上述性状的相关程度 ,进一步探讨了血浆VLDL浓度的双向选择效应。研究结果表明 ,二世代前期(19～ 4 3周 )产蛋量高脂系较高 (P <0 .0 5 ) ,在中后期 (44～ 6 2周 )低脂系产蛋量较高 (P <0 .0 5 ) ,全期 (19～ 6 2周 )产蛋量高、低脂系间差异不显著 (P >0 .0 5 ) ;二世代母鸡血浆VLDL与前期 (19～ 4 3周 )产蛋量呈显著的正表型相关 (P <0 .0 5 )和中等程度的正遗传相关 ,与中后期 (44～ 6 2周 )产蛋量呈显著的负表型相关 (P <0 .0 5 )和中等程度的负遗传相关 ,与全期产蛋量呈极低的正表型相关 (P >0 .0 5 )和正遗传相关。二世代母鸡蛋重低脂系较高 ,但两系间差异不显著 (P >0 .0 5 )。血浆VLDL浓度与蛋重呈较低的负表型相关和中等程度的负遗传相关 ,表明对血浆VLDL浓度的低向选择有可能使中后期蛋重提高。     

肉鸡血浆VLDL浓度的选择效应——对产蛋性能的影响

以零世代和一世代高、低脂系肉鸡为素材 ,个体记录高、低脂系母鸡产蛋性能 ,屠宰测定零世代 54周龄母鸡腹脂重 (率 ) ,探讨肥度性状与产蛋性能的关系 ,并研究零世代、一世代高、低脂系产蛋性能选择效应。结果表明 :在限饲条件下 ,腹脂重 (率 )与开产日龄、产蛋量表型相关很弱。腹脂重 (率 )与蛋重呈负表型相关趋势 ;零世代高、低脂系产蛋性能差异不显著。一世代低脂系比高脂系早开产 6.7d,低脂系 4 0周龄和 54周龄产蛋量显著高于高脂系 ,表明对血浆 VLDL浓度的选择使产蛋性能产生了有益的间接反应     

肉鸡血浆VLDL浓度的选择效应——对产蛋性能的影响

以零世代和一世代高,低脂系肉鸡为素材,个体记录高,低脂系母鸡产蛋性能,屠宰测定零世代５４周期母鸡腹脂重（率）,探讨肥度性状与产蛋性能的关系,并研究零世代,一世代高,低脂系产蛋性能选择效应。结果表明：在限饲条件下,腹脂重（率）＿与开产日龄、产蛋量表型相关很弱。腹脂重（率）与蛋重呈负表型相关趋势,零世代高、低脂系产蛋性能差异不显著。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     

肉种鸡血浆VLDL浓度与肥度性状的相关研究

以肉种鸡为试验素材，分别测定其16周龄、54周龄血浆VLDL浓度和54周龄腹脂重（率），探讨肉种鸡血浆VLDL浓度与肥度性状和体重的关系。结果表明：16周龄公、母鸡血浆VLDL浓度差异不显著，54周龄母鸡血浆VLDL浓度显著高于公鸡；54周龄母鸡血浆VLDL浓度显著高于16周龄母鸡，54周龄公鸡血浆VLDL浓度小于16周龄公鸡；54周龄公鸡腹部无脂肪沉积，母鸡腹脂重为120.9g，腹脂率为3.22%；16周龄血浆VLDL浓度与54周龄体重呈显著相关，而与54周龄腹脂重（率）相关不显著，54周龄血浆VLDL浓度与体重、腹脂重（率）相关不显著。     

肉种鸡血浆VLDL浓度与肥度性状的相关研究

以肉种鸡为试验素材 ,分别测定其 16周龄、5 4周龄血浆VLDL浓度和 5 4周龄腹脂重 (率 ) ,探讨肉种鸡血浆VLDL浓度与肥度性状和体重的关系。结果表明 :16周龄公、母鸡血浆VLDL浓度差异不显著 ,5 4周龄母鸡血浆VLDL浓度显著高于公鸡 ;5 4周龄母鸡血浆VLDL浓度显著高于 16周龄母鸡 ,5 4周龄公鸡血浆VLDL浓度小于 16周龄公鸡 ;5 4周龄公鸡腹部无脂肪沉积 ,母鸡腹脂重为 12 0 .9g ,腹脂率为 3 .2 2 % ;16周龄血浆VLDL浓度与 5 4周龄体重呈显著相关 ,而与 5 4周龄腹脂重 (率 )相关不显著 ,5 4周龄血浆VLDL浓度与体重、腹脂重 (率 )相关不显著     

蛋鸡血浆极低密度脂蛋白浓度的变化规律及其选择效应研究

以雅发祖代种鸡为研究材料．用比浊法测定鸡血浆极低密度脂蛋白（ＶＬＤＬ）浓度．试验结果表明，母鸡血浆ＶＬＤＬ浓度随鸡周龄的增大而持续增加．产蛋期个体间血浆ＶＬＤＬ浓度的变异系数为１５％～６９％，２９周龄母鸡血浆ＶＤＬ浓度的遗传力为０．２４．血浆ＶＬＤＬ浓度与腹脂重、腹胀率、肝脂含量均呈正表型相关趋势．２９周龄血浆ＶＬＤＬ浓度与产蛋前期产蛋量、１８周龄体重、开产日龄、蛋黄重、蛋黄比例、蛋黄蛋白比例的遗传相关系数分别是０．２７，０．３８，－０．３３，０．２３，０．２５，０．２２．     

ACOX3基因多态性对鸡体脂沉积的影响

文章通过分析酰基辅酶A氧化酶（Acyl-Coenzyme A Oxidases 3,ACOX3）基因单核苷酸多态性与鸡脂肪性状的关系,旨在了解该基因对鸡体脂沉积的影响。以东北农业大学高、低脂双向选择品系肉鸡为材料,采用PCR-RFLP方法检测ACOX3基因的多态性,并分析该基因多态性与鸡脂肪性状的关系。结果表明,ACOX3基因c.-228C>T突变位点在肉鸡高、低脂双向选择品系第10、11世代混合群体中,对腹脂重、腹脂率和血浆VLDL浓度有显著影响（P<0.05）;c.-442A>C突变位点在第8-11世代混合群体低脂系中,对腹脂重有显著影响（P<0.05）;c.27035A>G突变位点在第10、11世代混合群体低脂系中,对血浆VLDL浓度有显著影响（P<0.05）;c.16802C>T突变位点在第11世代低脂系中,对腹脂重、腹脂率有显著影响（P<0.05）。结果显示,ACOX3基因对鸡的体脂沉积有重要影响。ACOX3基因c.-228C>T突变位点对鸡脂肪性状有显著影响,可以尝试作为遗传标记对脂肪性状进行分子标记辅助选择。     

限饲对肉种母鸡产蛋期产蛋性能和蛋品质的影响

试验为2×2的两因子试验设计。选用23周龄高低脂系肉种母鸡各384羽,分为4个处理组,每组12个重复,每个重复16只。当产蛋率达到5%时,进行日粮处理,高低脂系母鸡分别饲喂中国鸡饲养标准(NY/T33-2004)推荐的需要量和75%的需要量。试验持续到54周龄。结果表明,饲料采食量与品系在产蛋量、蛋重上存在显著的交互作用(P0.05)。不同品系对产蛋量和破蛋率有着显著的影响(P0.05)。高脂系母鸡的产蛋量显著高于低脂系,破蛋率显著低于低脂系(P0.05)。采食量限饲显著降低了蛋重,显著提高了蛋形指数和产蛋量(P0.05)。不同品系在产蛋量、蛋重、破蛋率、蛋黄颜色上表现出不同的母体效应(P0.05)。     

肉鸡高、低脂系体脂性状和血清生化指标的比较分析

以东北农业大学肉鸡高、低腹脂双向选择品系为试验材料,分析第11、12世代肉鸡体重、体脂性状和血清生化指标在两系间的差异。结果表明,在体重和体脂性状方面,肉鸡高脂系的腹脂重、腹脂率、肝脏重极显著高于低脂系肉鸡的相应性状(P<0.01),而肝脏内脂肪含量性状差异则只达到显著水平(P<0.05);对于胸肌和腿肌内脂肪含量等性状,高脂系则极显著低于低脂系肉鸡(P<0.01);与此同时,高、低脂系间7周龄体重则无显著性差异(P>0.05)。在血清生化指标方面,高脂系肉鸡血清中HDL-C、VLDL、FFA、apoB和胰岛素(Insulin)水平高于低脂系肉鸡的相应指标(P<0.01);相反Glu和LDL-C低于低脂系的相应指标(P<0.01);高、低脂系间TG、TC的水平则无显著差异(P>0.05)。上述结果表明,对肉鸡腹脂率的持续定向选择对血液中脂质代谢各项生化指标具有显著的影响。有助于理解肉鸡血脂代谢与体脂沉积的关系,对低脂肉鸡的进一步选育具有积极的指导意义。     

蛋鸡周龄对蛋质量和蛋黄占蛋白比例的影响

为了了解蛋鸡周龄对鸡蛋质量及其各成分含量的影响,以同一批次90只新杨褐蛋鸡为试验对象,在相同的饲养条件下,从20周龄开始,每4周集蛋一次分析周龄对蛋质量和蛋黄占蛋白比例的影响。结果表明,随周龄的增加,蛋质量及其各成分质量、蛋黄质量占蛋质量的比例、蛋黄占蛋白的比例等逐渐增加;蛋白质量、蛋壳质量占蛋质量的比例下降。不同周龄蛋质量与蛋黄占蛋白的比例之间具有负相关关系,且不同周龄相关程度不同。由不同周龄蛋质量及蛋黄、蛋白占全蛋比例的回归分析得知,在同一周龄,随蛋质量的增加,蛋黄占全蛋的比例下降,蛋白占全蛋的比例增加,且以36周时的变化幅度最大。蛋质量相同时,20周时蛋黄占蛋质量的比例最小,而56周时蛋黄占蛋质量的比例最大。周龄对蛋质量及蛋黄占蛋白的比例有显著的影响,随周龄的增加蛋质量及蛋黄占蛋白的比例增大。     

Study on the Relationship between Plasma very Low Density Lipoprotein Concentration and Egg Composition Traits in Layer Type Chickens

The chickens used in this study were from a pure line of brown shell egg-type(YAFA) female grandparents of 17-week-old.Plasma very low density lipoprotein(VLDL) concentration was measured with turbidimetrie assay ,The experimental results showed that there was a close rela-tionship between plasma VLDL concentration and egg composition traits,and a positive phenotypic correlation trend was found betewwn 29-week plasma VLDL concentration and 44-week yolk weght,and the genetic correlation coefficient was 0.234, Both the phenotypic and genetic correlations betewwn 29-week plasma VLD concentration and albumen weight were neg-ative,Significant positive phcnotypie correlations ,were,however,observed between yolk ratio or the yolk/albumen ratio and 29-week plasma VLD concentration and their genetic correlation coeffieients were 0.250 and 0.223,respectively.     

The Influence of Selection for Plasma very Low Density Lipoprotein Concentration upon Production Performance in Layer Type Chickens

The chickens studied were from a pure line of brown shell egg-type(YAFA) female grandparents of 17-week-old.Plasima very low denstiy lipoprotein(VLDL) concentration was measured with turbidimetric assay.The experiment results showed that the phenotypic correla-tions between 29-week or 50-week plasma VLDL concentration and egg production (EP) were positive in the early stage of laying period,but those in the latter stage were negative,Selection for low plasma VLD concentration will decrease the EP in the early stage of laying period but in-crease the one in the latter stage,There was a significant negative phenotypic correlaiton between the atge at first egg (AFE) and 18-week body weight(BW),The phenotypic correlation between 29-week plasma VLDL concentration and the AFE was negative,AFE was influenced by BW and body fatness as well.There was significant positive phenotypic correlation between plasima VLDL concentration and body weights(BWs) at the same stage in laying period and the phenotypic correlation was aslo positive between 29-week plasma VLDL concentration and the BW at middle stage of laying period,indicating that selection for low plasma VLDL concentration would reduce BWs at various stages to different degree.     

The Change of Plasma very Low Density Lipoprotein Concentration Pre-orPost-Feeding and in Conrrelation with Body Fatness Traits in Broiler Chickens

Blood samples were taken from birds,from a commercial line of broiler chicken,being in a fully fed state and in fasting state for 2,4,6 hours respectively at 49d of age and plasma very low density lipoprotein (VLDL) concentration was measured with turbidimetric assay.The experiment results showed that the variation coefficients of plasma VLDL concentration mersured at four different times were 58.11%,74.39%,69.70%,47.83%,respectively for male broilers,and 41.82%,60.87%,59.26%,50.0% for female broilers respectively.Plasma VLDL concentration decreased with the fasting time.There was a significant positive phenotypic correlation between abdominal fat weight,percentage of abdominal fat and plasma VLDL concentration for the birds being in fully feeding state,and the correlation decreased or no longer existed for the bired being in fasting state.The conclusion was that for practically application of plasma VLDL content selected in broiler chicken breeding,blood samples should be collected from birds being in feeding state.     

孵化期间蛋内组成成分变化规律的研究

通过测定鸡蛋蛋白、蛋黄及胚胎中钙、粗蛋白和粗脂肪含量,探讨孵化期间蛋内组成成分的变化规律.结果表明: 胚胎发育过程中蛋白提供20.2%的钙,蛋黄提供10.0%的钙,蛋白和蛋黄钙含量的变化具有一定的互补性;胚胎中钙含量不断增加.蛋白中粗蛋白含量高,粗脂肪含量低,粗蛋白与粗脂肪含量变化趋势基本相反.除12胚龄外,蛋黄中粗脂肪含量不断降低; 18～21胚龄是脂肪代谢旺盛期.胚胎粗蛋白含量不断降低,粗脂肪含量不断增加,两者呈负相关.     

Effects of One Generation Divergent Selection for Plasma very Low Density Lipoprotein Concentration

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浙江省主要蛋鸭品种蛋品质测定和遗传力估计

测定了浙江省2个地方鸭品种共6个品系各50个蛋的蛋形指数、蛋壳强度、蛋壳厚度、蛋比重、哈氏单位、蛋白高度、蛋黄重和蛋黄比率等8项蛋品质指标,进行了品种和品系间的多重比较和各性状的遗传力估计。结果表明：品种间比较显示,绍兴鸭的蛋壳质量显著高于缙云麻鸭,缙云麻鸭蛋白和蛋黄品质优于绍兴鸭;品系间比较显示,绍兴鸭带圈白翼梢系和绍兴鸭青壳系蛋壳质量最好,优于其他品系,缙云麻鸭3个品系的蛋白和蛋黄品质差异较小;蛋品质各性状的遗传力估计结果显示蛋比重和蛋壳厚度遗传力较高,分别为0.72和0.47,而哈氏单位性状最低（0.06）。结果提示,浙江省2个地方鸭种的蛋比重和蛋壳厚度两项指标可通过遗传选育进行改良,而蛋白高度、蛋黄比率和哈氏单位应通过环境控制来提高。     

产蛋母鸡血浆肝及蛋铁硒含量的研究

将 2 78日龄罗曼蛋鸡随机分成 3组 ,以含 2 5mgFe ,含 0 .2mgSe/kg日粮 (对照组 ) ,5 2 5mgFe,1.2mgSe/kg日粮(试验Ⅰ组 ) ,10 2 5mgFe,2 .2mgSe/kg日粮 (试验Ⅱ组 )饲喂 8周 ,结果表明 ,与对照组比较 ,试验组血浆铁硒含量、蛋黄铁硒含量、蛋白硒含量、肝铁硒含量均有大幅度提高。相关性检验表明 ,日粮铁与血浆铁、蛋黄铁 ,血浆铁与蛋黄铁 ,日粮硒与血浆硒、蛋黄硒及蛋白硒 ,血浆硒与蛋黄硒及蛋白硒 ,均呈强正相关 ,P <0 .0 1。这些结果提示 ,通过高铁高日粮可以大幅度提高蛋中铁硒含量 ,产蛋母鸡是日粮中铁硒向蛋中转运的良好载体