正反反复选择下近交对褐壳蛋鸡饲料利用率和繁殖性状的影响

本文估计了褐壳蛋鸡洛岛红(AA)和浅花苏赛克斯(BB)在正反反复选择(RRS)下的近交系数,分析了近交对选择标准饲料利用率及其相关性状和繁殖性状的影响。试验群体由两纯种及其正反交组合和相应的对照组组成。经过7个世代的RRS和近交试验,试验组AA和BB(括弧里为对照组1AA和1BB)用系谱材料计算出的平均累积近交系数分别为2.58％和3.23％(9.33和8.17%)或每代为0.43%(1.35%),用有效群体含量估计出的AA与BB的相应数值为2.91％与2.83％(5.84%与5.92％)或每代为0.42％(0.86％)。1％近交系数导致的孵化率和饲料利用率的近交衰退较严重(0.5％和0.4％),其次是产蛋性状(约0.3％),而体重和蛋重只有0.1％左右。在本研究中,通过连续7代的RRS与合适的留种率等措施,成功地将闭锁群体的近交系数控制在3%以下的低水平,消除或减轻了近交对饲料利用率等重要经济性状的不利影响。     

蛋鸡不同杂交组合主要经济性状的杂种优势的研究

通过对蛋鸡５个纯系和纯系间５个杂交组合的一个产蛋周期的生产性能测定，研究不同经济性状的杂种优势情况，以及不同杂交组合的杂种优势率。研究表明，极限性状受精率和孵化率在纯系水平较一般的情况下可以产生较大的杂种优势，而在纯系水平较高的情况下，由于受极限的限制，不可能表现明显的杂种优势；产蛋率和开产日龄的杂种优势率较高，料蛋比、成活率和７２周龄产蛋重的杂种优势略低一些，体重具有较强的杂种劣势，日耗料和蛋重的杂种优势（或劣势）率很低；遗传距离较远的品种（系）之间杂交产生杂种优势的可能性和程度较大，因此推荐用白来航和褐壳蛋鸡杂交生产商品蛋鸡。     

用铝硅酸钠提高肉鸡饲料转化率

最近美国一州立大学试验证明,喂给肉鸡人工合成的铝硅酸钠(sodium aluminosilicate)水合物后,饲料消耗量下降,但鸡的体重、蛋的大小和蛋的孵化率保持不变。 1320只试验鸡其中一半鸡喂不加铝硅酸钠的饲料,另一半喂给含1.5％铝硅酸钠的日粮。试验期间每周称重,按体重配给饲料量。试验结果表明,32周龄开始直到60周龄,试验组饲料消耗量明显低于对照组,而产蛋量     

笼养蛋鸡疲劳症的发生及防治

笼养蛋鸡疲劳症又称笼养蛋鸡骨质疏松症，是笼养产蛋鸡的一种全身性骨骼疾病。几乎发生在所有笼养产蛋鸡群中，产蛋期发病率为1％～10％。常发生于产蛋高峰期。1病因　　笼养蛋鸡疲劳症主要由于严重缺钙而引起。高产蛋鸡体重轻、采食量小、饲料利用率高和性成熟早，钙源无法满足蛋壳形成及维持骨骼强度所需，导致钙负平衡；过度粉碎的石灰石粉钙的利用率较低；炎热季节蛋鸡采食量减少而饲料中钙水平未相应增加；长期持续高产需要较多的钙，等等，都可能导致笼养鸡疲劳症。此外，饲料中磷含量在临界值(总磷0.5％)以下，容易在初产蛋鸡群中诱…     

伊莎B-380褐壳蛋鸡不同世代种蛋受精率和孵化率的比较

用伊莎Ｂ—３８０褐壳蛋鸡祖代Ａ、Ｂ、Ｃ、Ｄ四个品系,按Ａ×Ｂ、Ｃ×Ｄ和ＡＢ×ＣＤ的杂交方式分别生产父母代和商品代。通过比较分析,伊莎Ｂ—３８０褐壳蛋鸡父母代与商品代种蛋的受精率分别为８３．９２％和８６．１９％,受精蛋孵化率分别为５７．２１％和７５．４１％,入孵蛋孵化率分别为４７．９８％和６４．９９％。经检验,父母代与商品代间的种蛋受精率无显著性差异（Ｐ＞０．０５）,入孵蛋孵化率与受精蛋孵化率差异极显著（Ｐ＜０．０１）,表明受精率的杂种优势,四元杂交与二元杂交无差异;孵化率的杂种优势,四元杂交比二元杂交更明显。     

新杨绿壳蛋鸡和白来航鸡快慢羽品系产蛋性能比较

本试验就新杨绿壳蛋鸡、白来航鸡快羽和慢羽品系的部分产蛋性能进行比较研究。结果表明:白来航鸡快羽品系的25~45周龄总产蛋数、49周龄蛋重、母鸡体重和蛋壳颜色均显著高于新杨绿壳蛋鸡(P0.01),且优于白来航慢羽品系的同类性状;25~45周龄总产蛋数与49周龄蛋重、母鸡体重和蛋壳颜色呈极显著正相关(P0.01);49周龄蛋重与体重和蛋壳颜色呈极显著正相关(P0.01);49周龄母鸡体重和蛋壳颜色呈极显著正相关(P0.01)。总体来看,白来航鸡快羽和慢羽品系的性状变异系数小于新杨绿壳蛋鸡,其变异系数均小于10%。新杨绿壳蛋鸡的性状变异系数稳定性差,平均变异系数超过10%,仅蛋重和蛋壳颜色的变异系数略低于10%,这说明在规模化生产时,新杨绿壳蛋鸡的选育还有待加强,从而使产蛋性状更加稳定。     

产蛋鸡体重均匀度对产蛋高峰期的影响

在蛋鸡的生产和培育过程中,鸡群的体重均匀度往往未引起足够的重视,而体重均匀度是影响蛋鸡产蛋性能和产蛋高峰期的重要因素之一。为进一步探讨体重均匀度对产蛋高峰期的影响,我们做了如下试验。一、材料与方法1.实验饲料自配产蛋鸡全价料。2.实验鸡群罗曼蛋鸡(凤台大兴鸡场)。     

蛋比重对孵化率的影响

<正>影响种蛋孵化率的因素很多,其中蛋比重是影响种蛋孵化率的因素之一。一般认为蛋比重在1.080级以上的种蛋,都可获得较好的孵化率。为了进一步验证蛋比重对种蛋孵化率的影响,我们利用来航蛋鸡(白壳蛋系)和星杂579蛋鸡(褐壳蛋系)的种蛋进行了本试验。现将试验情况报道如下: 材料与方法 1.种蛋来源:试验种蛋来自红兴隆科研所种鸡场自行培育42周龄来航蛋鸡1500只和由北京市第二种鸡场引进星杂579蛋种鸡1500只,连续采种蛋3天。     

钙源颗粒大小可影响产蛋鸡骨质性能

加拿大阿尔伯特大学、亚特兰大家禽研究所和新斯科舍省农业大学进行了一项联合研究，他们针对3个地方石灰岩作为蛋鸡饲料潜在钙源的可行性进行了试验。对石灰岩的体外溶解性进行了估测。以2种颗粒大小（磨碎型：100％／小颗粒；混合型：67％小颗粒＋33％大颗粒）进行添加。他们检测了试验鸡只的产蛋量、采食量、体重和蛋品质，并在产蛋结束后检测蛋鸡的骨密度、断裂强度、灰分和钙含量。结果显示，饲喂不同钙源饲料的蛋鸡采食量、体重、产蛋量、蛋重和蛋比重没有差异。与饲喂磨碎型钙源的鸡只相比，饲喂混合型颗粒大小钙源的试验鸡在27-70周龄采食量较高，其骨矿化作用也较好。研究者认为，这3种石灰岩可被用于蛋鸡的商业钙源。另外，大颗粒的钙能提高骨密度。     

饲粮缬氨酸水平对蛋鸡生产性能、蛋品质及血清生化指标的影响

本文旨在研究饲粮不同缬氨酸水平对蛋鸡生产性能、蛋品质及血清生化指标的影响,并探讨蛋鸡饲粮中缬氨酸的最适添加量.试验选用720只体重相近的40周龄的海兰褐壳蛋鸡,随机分成5组,每组4个重复,每个重复36只鸡,分别饲喂缬氨酸水平为0.6％、0.7％、0.8％、0.9％、1.0％的饲粮,试验期为56 d.结果表明:1)0.8％水平组料蛋比和1.0％水平组平均日采食量分别最低,与其他各组均差异显著(P＜0.05);各组产蛋率、平均蛋重和日产蛋均重均无显著差异(P＞0.05).2)0.8％水平组蛋壳强度最大,1.0％水平组蛋清蛋白质含量最低,与其他各组均差异显著(P＜0.05)或有显著的趋势(P＜0.10);各组蛋壳厚度、哈夫单位、蛋黄颜色、蛋白高度、蛋黄和蛋清相对重均无显著差异(P＞0.05).3)0.8％水平组血清葡萄糖含量最高,显著高于其他各组(P＜0.05);0.8％水平组血清尿素氮和尿酸含量最低,总氨基酸含量最高,与其他各组均有差异显著的趋势(P＜0.10).4)二次曲线分析表明:当饲粮代谢能为11.31 MJ/kg、粗蛋白质水平为15.81％、赖氨酸水平为0.77％时,以料蛋比为评价指标,产蛋高峰期蛋鸡缬氨酸需要量为0.78％,以蛋壳强度和血清白蛋白含量为评价指标,缬氨酸需要量分别为0.81％和0.75％.由此可知,基础饲粮中添加一定量的缬氨酸可降低产蛋高峰期蛋鸡料蛋比,增强蛋壳强度和提高血清葡萄糖含量.     

Performance of indigenous, Khaki Campbell and their reciprocal crossbred layer ducks under different management systems

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.     

Effect of intensity of eggshell pigment and illuminated incubation on hatchability of brown eggs

The effects of intensity of brown eggshell pigment (light (LBP), medium (MBP) and dark (DBP)) and light intensity during incubation (low and high, 900 to 1380 and 1430 to 2080 lux, respectively) on eggshell characteristics, embryonic growth, hatchability traits, chick hatching weight and hatching time were investigated using eggs from a meat-type breeder (Hybro) flock at 32, 36 and 41 weeks of age in three trials. With eggs of similar weights the intensity of brown pigment was not associated with eggshell weight and thickness, and did not influence embryo weight and egg weight loss during incubation. The shade of brown pigment of eggs laid by young hens influenced the percentage hatchability (HP) of eggs incubated under light. Illuminated incubation improved HP of LBP eggs (compared with MBP and DBP eggs) from 32- and 36-week-old hens, but had no significant effect on HP of eggs from 41-week-old hens. Light intensity during incubation did not influence egg weight loss. High intensity of light during incubation reduced HP and increased early death percentage (EDP) in the LBP and MBP groups, and did not influence HP and EDP in the DBP group. Brown eggshell pigment and intensity of light during incubation did not influence hatching time. It is concluded that the shade of brown pigment, intensity of light during incubation and age of the breeder hens influenced the hatchability performance of embryos from brown eggs. Light during incubation improved the hatchability of embryos in light brown eggs laid by young hens and the shade of brown pigment of eggs laid by older hens did not influence hatchability under illuminated incubation. High intensity of light during incubation reduced hatchability of light and medium brown eggs, but not the dark brown eggs.     

The Impact of Yeast Culture Residue on the Suppression of Dietary Aflatoxin on the Performance of Broiler Breeder Hens

A study was conducted to examine the effect of yeast culture residue (YCR) on the suppression of aflatoxicosis in broiler breeder hens. One hundred twenty, 35-wk-old, Cobb broiler breeder hens of the same cross were fed diets supplemented with aflatoxin (AF) (0 or 3 mg/kg) and YCR (0 or 2 lb/ton) singly and combined in a 2 × 2 factorial designed experiment. The birds were randomly assigned to pens with 3 replicates of 10 females and 1 male per treatment. Eggs laid by the hens were collected daily, stored at room temperature, and incubated every 7 d for 3 wk. Response variables analyzed were mean percentage of fertility, hatchability, hen-day egg production, egg weight, chick weight at hatch, and embryonic mortality over the 3-wk treatment period. At the end of 3-wk treatment, blood was collected from the hens and analyzed for total protein, globulin, and albumin. Aflatoxin did not negatively affect fertility. However, hen-day egg production (57.6%), percentage of hatchability (67.6%), embryonic mortality (24%), serum total protein, globulin, and albumin were significantly (P < 0.05) affected by AF. Hatch of fertile eggs from the AF-fed hens was significantly lower than the control (67.6 vs. 78.5%). The inclusion of YCR in the AF-treated diet raised the level of hatchability (74.9 vs. 67.6%), egg production (65.83 vs. 57.26%), and lowered embryonic mortality (16.8 vs. 24%). Serum globulin and albumin were lowered in the AF-fed hens but was partially restored with the addition of YCR. The data demonstrated that YCR may enhance the performance of broiler breeder hens that are provided feed contaminated with AF.     

Long-term egg production and heterosis in quail lines after within-line or reciprocal recurrent selection for high early egg production

1. Four Japanese quail lines were developed using 13 generations of reciprocal recurrent (lines AA and BB) or within-line selection (lines DD and EE) for high egg number until 98 d of age. In these lines and their reciprocal crosses, egg production, egg weight and mortality were monitored for up to 21 months to evaluate the impact of selection method and line origin on long-term production and heterosis. 2. Both hen-housed total egg number (EN) and hen-day egg laying rate (ELR) were consistently lower in recurrent lines than in lines under within-line selection: after 13 months of test, the difference was -47.1 eggs for EN and -20% for ELR%, whereas mortality was similar at around 20%. 3. Line EE was the best pure line for early egg production (55.2 eggs at 98 d of age) and also gave eggs which were consistently about 2 g larger than those from line DD but it had the highest overall mortality (78.5%) of all lines. On average, line DD laid 399 eggs (EN) over the whole experiment, 84 more than Line EE. 4. Crossbreds from the 2 types of pure lines and line DD had similar patterns and rates of egg production during the whole experiment, as indicated by the similarity of the curves adjusted for those lines by using the monomolecular model for EN and the modified compartmental model for ELR. 5. However, heterosis was higher from recurrent selection lines and it increased more with time than did heterosis from within-line selection lines.     

Self-selection of dietary protein and energy by turkey breeder hens

1. An experiment was conducted to determine the effects of self-selection of dietary protein and energy by turkey hens on reproductive performance in a warm environment. 2. Dietary self-selection had no significant effect on egg production, egg weight, or body weight of turkey hens. 3. Fertility and hatchability of eggs produced by self-selecting hens were significantly reduced compared to eggs from control hens fed on a complete diet. 4. Protein intake was significantly reduced among self-selecting hens when compared to control hens fed on a complete diet (P less than or equal to 0.001). 5. Food and energy intake decreased as the ambient temperature increased. Nevertheless, protein intake of self-selecting hens increased over the course of egg production despite decreasing food intake. Therefore, self-selecting hens preferred a diet with a greater protein content (g protein/kg diet) in the last 10 weeks of egg production than during the first 10 weeks of egg production.     

Inbreeding and heterosis effects on quantitative traits in a White Leghorn population under long-term reciprocal recurrent selection

1. Inbreeding and heterosis effects for quantitative traits were estimated in two White Leghorn lines selected with reciprocal recurrent selection (RRS) since 1950. 2. Pedigreed progeny were produced from full-sib, half-sib and unrelated pure line as well as reciprocal cross line matings to estimate inbreeding and heterosis effects "within sires". 3. Inbreeding effects estimated as linear regressions agreed well with estimates considering inbreeding as fixed effect. The inbreeding depression per 10% inbreeding was highest for hatchability (6-7%), intermediate for production-related traits (3%), and about 1% for shell quality, body weight and egg weight. 4. Heterosis effects were estimated by comparing pure line and cross line progeny of the same sires. 5. Results indicate considerably less heterosis for egg production than found earlier, which is interpreted as a consequence of pure line selection.     

人参提取物对蛋鸡产蛋性能、蛋品质、血清生化指标及经济效益的影响

文章旨在评估日粮添加不同水平人参提取物对蛋鸡产蛋性能、蛋品质及血清生化指标的影响。试验选择产蛋性能一致的450只海兰褐壳蛋鸡,随机分为3组,每组5个重复,每个重复30只。对照组饲喂基础日粮,处理组分别在基础日粮中添加0.04%和0.08%人参提取物,试验共进行6周。结果：与对照组相比,0.04%和0.08%人参提取物组产蛋率分别显著提高10.21%和8.77%（P＜0.05）,平均蛋重分别显著提高11.68%和9.07%（P＜0.05）。0.04%人参提取物组料蛋比较对照组显著降低6.51%（P＜0.05）,蛋壳颜色较对照组显著提高26.50%（P＜0.05）。对照组血清胆固醇浓度较处理组分别显著提高52.02%和58.32%（P＜0.05）。0.04%人参提取物组血清超氧化物歧化酶活性较对照组显著提高30.50%（P＜0.05）。0.04%和0.08%人参提取物组血清IgG和IgM浓度较对照组分别显著提高53.47%、60.72%和36.44%、42.43%（P＜0.05）。与对照组相比,0.04%和0.08%人参提取物组盲肠乳酸杆菌含量分别显著提高15.13%和12.82%（P＜0.05）。结论：在本试验条件下,日粮添加0.4?g/kg人参提取物可以提高蛋鸡饲料效率和蛋壳颜色。 [关键词]人参提取物|蛋鸡|产蛋性能|蛋品质|血清生化     

Influence of hormonal extracts on hens producing eggs with non-calcified or partially calcified shells and factors associated with this condition.

1. Daily injection of hypothalameal extract (HE) and adenohypophyseal extract (AE) into hens aged 56 or 67 weeks for 14 d did not significantly influence the production of shell-less (SL) or ultra-thin-shell (UTS) eggs. 2. The injection of HE significantly increased hard-shell (HS) egg production in the younger hens. 3. Neither AE nor HE affected egg weight, serum calcium, gain in body weight or food consumption. 4. In a third experiment hens selected for poor egg production laid at a rate of 58% of which 36% were SL, 29% UTS and 35% HS eggs. Whereas the production rate of the good layers was 65% of which 1-4% were SL and 1-4% were UTS eggs. 5. Specific gravity of HS eggs, serum calcium, weight of ovary, oviduct, or adenohypophysis did not differ between good and poor layers. 6. Since SL and UTS eggs are easily overlooked the decrease in egg production with age may be as great as indicated by normal production records; the problem may be concerned more with the mechanism of shell formation.     

肉种鸡血浆极低密度脂蛋白质量浓度双向选择的效应

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。