淮南麻黄鸡生长曲线拟合及开产性状相关分析

采用Gompertz、Logistic和von Bertalanffy 3种模型对淮南麻黄鸡1～16周龄生长曲线进行了拟合研究,同时对20周龄体重、开产日龄以及开产蛋重等性状进行了相关分析。结果表明,在3种生长曲线模型中,von Bertalanffy模型在拟合度和预测淮南麻黄鸡1～16周龄体重效果相对较好,公、母鸡的拟合度(R2)分别为0.994和0.996,极限体重分别为2 200 g和1 333 g。淮南麻黄鸡20周龄体重、开产日龄与开产蛋重均呈正相关(P<0.01)。     

油麻鸡F2代产蛋性能表现

利用拜城油鸡公鸡与良凤花母鸡进行杂交得到油麻鸡F1代,再利用油麻鸡F1代母鸡与拜城油鸡公鸡回交得到油麻鸡F2代,在圈养环境下将油麻鸡F2代与父母代良凤花鸡产蛋性能进行比较,结果表明油麻鸡F2代18周龄(120日龄)开产,最高产蛋率为87.94%,70%以上产蛋率维持16周,35周龄蛋平均重为53g,到44周龄每只平均产蛋量为119.48枚,F2代母鸡平均体重为2183g,公鸡平均体重为2935g;父母代良凤花鸡26周龄(182日龄)开产,最高产蛋率为79.01%,70%以上产蛋率维持4周;35周龄蛋平均重为59g,到44周龄每只平均产蛋量为78.29枚,母鸡平均体重为3 394g。通过比较可知,油麻鸡F2代除蛋重和体重比父母代良凤花鸡轻外,其他性能均高于父母代良凤花鸡,同时将油麻鸡F2代产蛋性能与纯种拜城油鸡产蛋性能比较,油麻鸡F2代比纯种拜城油鸡体重、产蛋性能均高。     

如皋黄鸡产蛋性能与遗传参数分析

研究以如皋黄鸡第4世代的15个家系351只母鸡为实验素材,测定开产日龄、开产体重、开产蛋重和40周龄产蛋数,统计各周龄群体产蛋率,估算开产性状和40周龄产蛋数的遗传参数。结果表明:如皋黄鸡开产日龄为(153.9±13.13)d,开产体重为(1 366.5±135.51)g,开产蛋重为(32.8±3.17)g,40周龄产蛋数为(101.0±8.94)个;高峰产蛋率为82.1%,70%以上产蛋率维持16周;开产日龄、开产体重、开产蛋重和40周龄产蛋数均为中等遗传力0.177~0.320;开产日龄、开产体重和开产蛋重间两两呈遗传正相关0.736~0.971,40周龄产蛋数与开产日龄、开产体重、开产蛋重间均呈遗传负相关-0.832~-0.639;性状间的表型相关性质和遗传相关一致,且均达到极显著的程度。     

三个地方鸡种产蛋性状配合力测定

以文昌鸡、如皋黄鸡、仙居鸡为素材,采用完全双列杂交测定配合力,统计各周龄体重、开产蛋重、产蛋高峰期蛋重、开产至40周龄料蛋比、开产至40周龄平均产蛋率,计算一般配合力和特殊配合力效应值.结果表明:父本对开产至40周龄平均产蛋率及入舍母鸡产蛋数贡献较大,母本对蛋重影响较大;文昌鸡♂×仙居鸡♀组合开产至40周龄料蛋比最低、40周龄产蛋数最高,为最佳配套组合,可在生产中配套使用.     

信宜怀乡鸡A品系第三世代产蛋性能测定与分析

笔者通过对怀乡鸡第三世代A品系产蛋性能的测定及分析,为信宜怀乡鸡的育种和保种利用提供了科学参考。对637只23周龄~52周龄母鸡的产蛋率、产蛋量、只均产蛋数、蛋重、种蛋合格率等产蛋性能进行统计分析,结果表明:怀乡鸡从开始产蛋到43周龄和52周龄,只均产蛋量分别为89.3枚和120.4枚;产蛋高峰为28周龄,产蛋率69.14%,55%以上的产蛋率能维持17周,60%以上的可维持13周;蛋重随着周龄的增加而增大,43周龄和52周龄蛋重分别为47.68 g和48.28 g。     

开产前体重对开产前体重对“京粉1号”父母代蛋种鸡生产性能的影响

为研究开产前不同体重水平对"京粉1号"父母代蛋种鸡生产性能的影响,试验自标准化蛋鸡舍15 616只20周龄"京粉1号"父母代蛋种鸡中,选取大于平均体重110%和介于平均体重105%~110%、100%~105%、95%~100%、90%~95%之间,以及小于平均体重90%的鸡各96只,共576只,依次分为1、2、3、4、5、6组。对6组鸡群提供相同的饲养环境、饲料配方和饲养管理,比较各组鸡群的开产日龄和达产蛋高峰日龄以及20~56周龄死淘率、产蛋率、蛋重、不合格种蛋率、入舍鸡单产、入舍鸡合格单产、不合格种蛋等8项指标。结果显示:开产前体重越大,鸡群开产越早,达产蛋高峰的日龄越早,全程产蛋率越高;体重与鸡群的蛋重相关性高,对部分不合格蛋的比例也有影响,但对鸡群的死淘率无影响,因而对入舍鸡单产及入舍鸡合格单产水平无影响。试验表明:"京粉1号"父母代蛋种鸡产前体重是后备鸡的培育关键,在后备期的饲养管理中,需促进鸡群适度增重,从而提高鸡群产蛋全程的生产性能。     

淮南麻黄鸡CRBP4基因多态性与早期产蛋性状和蛋品质的相关性

旨在探索CRBP4基因与淮南麻黄鸡产蛋性状和蛋品质的相关性,寻找可作为淮南麻黄鸡产蛋性状的重要分子标记.本研究利用PCR-SSCP技术和DNA测序技术对308只淮南麻黄鸡CRBP4基因遗传多态性进行检测及基因型分析,并对CRBP4基因的多态位点与早期产蛋性状和30周龄蛋品质进行相关分析.结果表明,在CRBP4基因exon2和exon3上存在3个突变位点,即C826T、C1240T和A1241G,其中C826T和A1241G导致了49 Se→4 9Leu和97 Ile→97Val突变,这3个突变位点都属于中度多态,基因型分布都处于Hardy-Weinberg平衡状态(P＞0.05).C826T位点与母鸡的开产蛋重呈显著相关,CC基因型有利于提高开产蛋重;构建的单倍型对开产蛋重的影响达到显著水平(P＜0.05).结果提示,CRBP4基因不同基因型和单倍型组合与淮南麻黄鸡开产蛋重存在相关性.     

如皋黄鸡的品种选育与利用

如皋黄鸡史书记载已有200多年历史,是江苏省优良地方家禽品种之一,2005年1月经江苏省畜禽品种管理委员会审定,定名—如皋黄鸡。如皋市畜牧科技人员从1976年起,对其进行了长达30年的品种选育、开发与推广应用工作,取得了良好的经济和社会效益。该鸡18周龄体重:公鸡1.5~1.75kg,母鸡1.25~1.45kg,开产日龄20周龄,50%产蛋率24周龄,入舍母鸡72周龄产蛋数192个,平均蛋重46~52g,料蛋比3.0~3.2:1,种蛋受精率93%~95%,入孵蛋孵化率86%~89%。以其为母本,三元杂交黄羽肉鸡43日龄体重1.2~1.5kg,料重比1.9~2.0:1,成活率98%以上。     

科普园地

品种推荐1 海兰褐蛋鸡品种简介 由美国海兰国际公司培育。该鸡具有抗病力强、产蛋率高、蛋品质好的优点。 其生产性能如下: 0 ～18 周龄成活率96%～98%。 22 周龄产蛋率达50% 。 高峰期产蛋率91%～96%。 80 周龄入舍鸡产蛋枚数323 枚。 平均蛋重63.3 g。 料蛋比2.3 ～2.5∶12 罗斯褐蛋鸡品种简介 为英国罗斯公司育成的Ⅳ系配套褐壳蛋鸡。可通过羽速和羽色自别雌雄。其商品代生产性能如下 18 周龄体重1.38 kg。 76 周龄体重2.2 kg。 0 ～18 周龄耗料7 kg。 19 ～76 周龄耗料45 kg。 开产周龄为18 ～20。 产蛋高峰期为25 ～27周龄。 76 周龄…     

育成后期体重对“罗曼褐”祖代D系鸡产蛋早期种用性能的影响

作者旨在探讨罗曼褐祖代D系母鸡育成后期体重对其开产后早期种用性能的影响。从18周龄的大群“罗曼褐”祖代鸡D系中选择90只作为试验鸡。用台秤逐只称重，按体重分为3组：大体重组30只（平均体重1.65 kg，大于标准体重），中体重组30只（平均体重1.45 kg,略高于标准体重1.382 kg），小体重组30只（平均体重1.25 kg,低于标准体重）。均按照“罗曼褐”祖代鸡的营养标准和饲养管理要求进行饲喂，测定育成后期体重与开产早期产蛋性能的关系，试验期10周。试验结果表明，中体重组在试验期内产蛋率曲线变化更符合该品种的标准，大体重组开产早，但是产蛋率下降也早。在试验期内各组的种蛋合格率变化趋势与产蛋率变化相似。在蛋用育成鸡的培育过程中要使其后期体重达到标准体重或略高于标准体重能够获得良好的生产效果。     

基于连接酶检测反应的PRL基因多态与清远麻鸡繁殖性能的相关性研究

旨在建立一个基于聚合酶链反应-连接酶检测反应的基因多态性并行检测系统,探讨鸡催乳素(PRL)基因的多态性,并分析其对优良地方鸡种——清远麻鸡繁殖性能的遗传效应。本研究应用PCR-LDR方法检测PRL8052T/C和PRL8113G/C基因型,并使用SAS软件进行最小二乘分析。结果,在8052T/C位点上,CT基因型个体的52周产蛋数显著高于TT型个体;在8113G/C位点上,CG基因型个体的开产日龄显著低于GG型个体,而其52周龄产蛋数却显著高于GG型个体。2个位点的单倍型对开产日龄和52周产蛋数也存在显著的效应,CTCG型个体具有较早的开产日龄和最高的52周龄产蛋数。结果表明,PRL基因多态性与清远麻鸡繁殖性状有相关关系,PRL 8052T/C和PRL 8113G/C杂合基因型可能是提高鸡繁殖性能的分子标记,利用单倍型进行标记辅助选择可能会获得更大的遗传进展。     

A comparison of the effects of feeding treatments and lighting on age at first egg and subsequent laying performance and carcase composition of broiler breeder hens

The effects of the growth curve from 15 to 20 weeks, age at photostimulation and pattern of photostimulus on sexual maturity, egg production and egg weight were evaluated in two trials with broiler breeder females to 56 and 34 weeks of age (housed in litter pens and individually caged, respectively). Carcase composition and reproductive morphology of hens varying in laying efficiency were measured in the second trial. Trial 1: Four growth curves were applied from 15 to 20 weeks to pullets housed in litter pens. Birds were transferred from 8- to 10-h photoperiods at 20 or 24 weeks of age, followed by weekly increments of one hour to reach a 16-h final photoperiod. Lower-than-recommended body weights at 20 weeks significantly delayed sexual maturity, reduced peak rate of lay, total eggs and mean egg weight. However, double-yolked egg production was lower, resulting in non-significant differences in settable egg numbers between body weight treatments. Birds reared to the heaviest body weight exhibited a significantly advanced sexual maturity, but total egg numbers, peak rate of lay and mean egg weight were not significantly affected. However, the laying of more double-yolked eggs resulted in a decrease in the number of settable eggs. Delaying photostimulation to 24 weeks significantly retarded sexual maturity, reduced total and settable egg numbers, and increased mean egg weight. A tendency for fewer double-yolked eggs was observed. Trial 2: At 19 weeks, birds were selected from the 4 body weight categories in Trial 1 and moved to individual cages in 8 rooms. Five lighting programmes were applied. The pattern of photostimulation applied did not affect any of the production traits measured. At 34 weeks, 24 birds were selected for the analysis of reproductive morphology, presence of internal or multiple ovulations, and carcase composition. Eight hens showing an early age at first egg and regular egg production records, 8 birds showing erratic laying performance and 8 non-layers were killed for this purpose. There were no differences in carcase composition or reproductive morphology between these groups. No internal ovulations or double or multiple ovarian hierarchies were observed. The results presented confirm that broiler breeders do not require a lighting stimulus in order to initiate ovarian activity and that, where no lighting stimulus is given, body weight or feeding level plays a critical role in stimulating the birds to attain sexual maturity. However, when a lighting stimulus is given, factors such as body weight and body composition become relatively less important in regulating the age at sexual maturity.     

Sequential studies of skeletal calcium reserves and structural bone volume in a commercial layer flock.

1. Production-induced osteoporosis in caged laying hens is thought to represent a major constraint to continued genetic development. 2. The relationship between body weight, egg production, skeletal abnormalities characteristic of osteoporosis, femur calcium and bone histology was examined in a flock of ISA Brown layers from 16 to 68 weeks of age. 3. Experiment 2 examined a flock of Lohmann browns for skeletal abnormalities characteristic of osteoporosis at 45 weeks of age and the severity of abnormalities was then related to body weight and production between 18 and 45 weeks of age. 4. Average body weight declined in the ISA flock between 35 and 45 weeks of age, which correlated with a loss of skeletal calcium reserves (15% to 20%) and with the induction of osteoporosis. Between 42 and 68 weeks of age, birds were able to replenish femur calcium levels. 5. Birds in the Lohmann flock showing severe skeletal abnormalities at 45 weeks of age experienced weight loss between 27 and 31 weeks of age, which was associated with a decrease in egg production of 18%. After 35 weeks of age, egg production of these birds recovered to similar levels as unaffected or mildly affected birds. 6. It seems likely that better standardisation of the equilibrium between growth, skeletal reserves, food intake and egg production can reduce osteoporosis, as well as improving the productive potential of modern laying strains.     

Heritabilities and genetic correlations of laying performance in Muscovy ducks selected in Taiwan

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.     

蛋鸡约束指数的初步研究

利用我场一个家系3个世代24只公鸡,192只母鸡。486个儿女资料,计算了包括开产日龄,开产体重,280日龄产蛋量,36周蛋重的约束指数,把约束指数应用于父系选育,结果表明约束选择有一定作用,并对其应用作了初步探讨。     

饲粮不同能量水平对产蛋初期肉种鸡产蛋性能、蛋品质和蛋组分的影响

本研究旨在研究饲粮不同能量水平对爱拔益加（ＡＡ）肉种鸡产蛋初期产蛋性能、蛋品质以及蛋组分的影响。试验采用单因子试验设计,选用 ２０周龄体重相近的 ＡＡ肉种母鸡 ３００羽,随机分为 ３组,每组 ５个重复,每个重复 ２０羽。在产蛋率达 ５％（２６周龄）后开始正式试验（２７～４０周龄）,对照组饲喂玉米 －豆粕型基础饲粮,高能组、低能组饲喂能量水平分别为基础饲粮能量 １２０％和 ８０％的饲粮,各组均限饲,且饲喂量相同,试验期为 ９８ｄ。结果表明：１）与对照组相比,高能组和低能组的产蛋率、蛋重显著降低（Ｐ＜０．０５）,低能组合格率显著高于对照组和高能组（Ｐ＜０．０５）,且随着饲粮能量水平降低,破蛋率显著降低（Ｐ＜０．０５）。２）与对照组相比,高能组肉种鸡 ３５、４０周龄的蛋黄颜色有显著提高（Ｐ＜０．０５）,低能组无显著变化（Ｐ＞０．０５）,且能量水平对其他蛋品质指标无显著影响（Ｐ＞０．０５）。３）与对照组相比,在 ３５周龄时,高能组的蛋黄相对重和蛋黄粗脂肪、蛋黄总胆固醇含量显著升高（Ｐ＜０．０５）,蛋黄粗蛋白质、蛋清粗蛋白质、蛋清粗脂肪含量显著降低（Ｐ＜０．０５）;低能组的蛋清相对重、蛋黄总胆固醇含量显著升高（Ｐ＜０．０５）,蛋清粗蛋白质含量显著降低（Ｐ＜０．０５）,各组蛋壳相对重和蛋清干物质、蛋黄干物质含量均无显著差异（Ｐ＞０．０５）。在 ４０周龄时,高能组的蛋清相对重、蛋壳相对重、蛋黄粗脂肪含量显著升高（Ｐ＜０．０５）,蛋黄相对重、蛋黄粗蛋白质含量显著降低（Ｐ＜０．０５）;低能组的蛋清相对重显著升高（Ｐ＜０．０５）,蛋黄相对重显著降低（Ｐ＜０．０５）;各组蛋清干物质、蛋黄干物质、蛋清粗蛋白质、蛋清粗脂肪、蛋黄总胆固醇含量均无显著差异（Ｐ＞０．０５）。上述结果表明,在肉种鸡产蛋初期,高能组较高的饲粮成本却导致了肉种鸡较差的产蛋性能,低能组的产蛋率虽然低于对照组,但合格率却有明显的优势,而且蛋品质及蛋组分不受影响。因此,低能量饲粮可能更有利于生产实践。     

Sodium bentonite as a component in layer diets

1. Two hundred and forty Amber-link pullets were individually caged in a naturally-ventilated laying house and fed one of four isoenergetic, isonitrogenous diets containing 0, 20, 40 or 80 sodium bentonite/kg for 44 weeks. 2. No significant dietary effects were observed between treatments with regard to body weight at 20 or 64 weeks, age at first egg, egg weight, Haugh score or egg shell thickness. 3. Significant positive linear responses were observed with live weight at first egg (P less than 0.01), food consumed/hen d (P less than 0.05) and faecal moisture percentage (P less than 0.01). Significant negative linear (P less than 0.01) responses were observed with bacterial counts in the proximal and distal ends of the intestine. 4. A significant negative quadratic (P less than 0.05) response was noticed with egg production per hen. 5. A significant negative cubic (P less than 0.01) response was found with food conversion ratio (g food/g eggs).     

Optimum isoleucine requirement of laying hens and the effect of age

1. Medium weight laying hens were used for an assay to determine their isoleucine requirement between 26 and 36 weeks of age and again between 46 and 56 weeks of age. 2. Two isoleucine-limiting mixtures were formulated with similar amino acid profiles, one containing 198 g and the other 110 g crude protein per kg diet. These mixtures were blended to give a series of 11 diets with isoleucine contents ranging from 7.6 to 3.8 g/kg. The lowest protein diet was also fed with a supplement of L-isoleucine. Each of the 12 diets was given to 5 groups of 24 laying hens. 3. The daily isoleucine requirement of individual laying hens was estimated to be 9.48 mg/g egg output plus 44.47 mg/kg body weight per day for the 1st period and 12.11 mg/g egg output plus 6.86 mg/kg body weight per day for the 2nd period. Calculated optimum intakes of isoleucine for various ratios of cost of input to value of output are tabulated. For example, for a flock of medium weight hens producing an average of 50 g daily egg mass, the optimum isoleucine intake (mg/hen d) varied between 760 and 890 varying for ratios of costs to egg prices. 4. It is concluded that the isoleucine required per day does not decrease during the first laying year despite a decrease in rate of egg output.     

Effect of enzyme preparation containing xylanase and beta-glucanase on performance of laying hens fed wheat/barley- or maize/soybean meal-based diets

1. A commercial enzyme preparation (Quatrazyme HP) containing xylanase and beta-glucanase was examined in two laying hen experiments with wheat/barley- or maize-based diets. The activities of other enzymes were measured also. Starch, cell wall contents and effects of Quatrazyme HP on in vitro viscosity of wheat, barley, maize and soybean meal were determined. 2. In the first experiment, 90 ISA Brown laying hens at 28 weeks of age were given a wheat/barley basal diet with or without 20mg of Quatrazyme HP, which provided 560 and 2,800 IU of xylanase and beta-glucanase/kg diet. In the second experiment, 66 ISA Brown laying hens at 45 weeks of age were given a maize/soybean meal basal diet with or without 20 mg of Quatrazyme HP/kg diet for 9 weeks. Egg production, egg weight, egg mass, feed conversion ratio and change in body weight were recorded as response criteria. 3. There was a significant improvement in feed conversion ratio with enzyme supplementation. Birds given an enzyme-supplemented diet gained 86 g while those fed on the unsupplemented diet lost 103 g of their body weight by the end of the experiment. 4. The enzyme preparation did not affect either egg production, egg weight or egg mass of birds fed on the maize/soybean meal diet. However, a significant improvement in feed conversion ratio was detected. Birds on either the supplemented or unsupplemented diet exhibited an increase in their body weight at the end of the experiment. 5. Addition of xylanase and beta-glucanase decreased in vitro viscosity of wheat, barley, maize and soybean meal. This effect was greater for wheat and barley than for maize and soybean meal. 6. It was concluded that the beneficial effect of using an enzyme preparation containing xylanase and beta-glucanase is not limited to wheat/barley-based diets but also occurs with maize/soybean meal-based diets.