Zelleke G, Moudgal R P, Asmare A
Andasa Livestock Research Center, ARARI, Bahir Dar, Ethiopia.
Br Poult Sci. 2005 Feb;46(1):119-23. doi: 10.1080/00071660400023961.
(1) Four breeding groups of Rhode Island Red and White Leghorn domestic fowl (RIR (female) x RIR (male), RIR (female) x WL (male), WL (female) x RIR (male) and WL (female) x WL (male)) were compared for fertility, hatchability, and their post-insemination sustainability, egg weight loss during incubation and uncovered yolk in abdominal cavity of dead in shell in order to understand the problems associated with the RIR breed in these respects. (2) Crossing RIR (female) with WL (male) or in reverse sex combinations did not improve fertility in comparison to pure RIR chickens and all these groups were less fertile than the pure WL. (3) Unlike fertility, hatchability in RIR improved with the change to either sex partner of the WL breed but the WL (female) x RIR (male) combination was similar to the pure WL (97.72 and 97.12%, respectively). In contrast, crossing RIR (female) with WL (male) resulted in an improvement (86.67%) as compared to pure RIR (76.67%) but still lower than the pure WL and WL (female) x RIR (male) cross. (4) Egg weight loss during incubation was more (20.16%) in pure RIR as compared to RIR (female) x WL (male) (17.13%), followed by WL (female) x RIR (male) (10.28%) and pure WL (9.57%). (5) There were more dead-in-shell embryos with yolks outside their abdominal cavity in pure RIR and their crosses as compared to pure WL breeds. (6) Fertility was sustained for longer in WL than other combinations with post-artificial insemination using constant number of spermatozoa. Fertility after a week of insemination tended to decrease more rapidly than hatchability on a fertile egg basis. (7) It is concluded that both sexes are responsible for the poor fertility in RIR but the female is responsible for poor hatchability and this poor performance is mainly due to greater egg weight loss during incubation.
(1) 比较了四组罗德岛红鸡和白来航鸡的繁殖情况（罗德岛红鸡（雌）×罗德岛红鸡（雄）、罗德岛红鸡（雌）×白来航鸡（雄）、白来航鸡（雌）×罗德岛红鸡（雄）以及白来航鸡（雌）×白来航鸡（雄）），涉及受精率、孵化率及其授精后的可持续性、孵化期间的蛋重损失以及死在壳内鸡胚腹腔中未覆盖的蛋黄情况，以便了解罗德岛红鸡品种在这些方面存在的问题。(2) 与纯罗德岛红鸡相比，将罗德岛红鸡（雌）与白来航鸡（雄）杂交或进行反性别组合并没有提高受精率，并且所有这些组的受精率都低于纯白来航鸡。(3) 与受精率不同，罗德岛红鸡的孵化率随着与白来航鸡品种的任何一方性伴侣的改变而提高，但白来航鸡（雌）×罗德岛红鸡（雄）组合与纯白来航鸡相似（分别为97.72%和97.12%）。相比之下，将罗德岛红鸡（雌）与白来航鸡（雄）杂交，与纯罗德岛红鸡（76.67%）相比有提高（86.67%），但仍低于纯白来航鸡和白来航鸡（雌）×罗德岛红鸡（雄）的杂交组合。(4) 与罗德岛红鸡（雌）×白来航鸡（雄）（17.13%）相比，纯罗德岛红鸡在孵化期间的蛋重损失更多（20.16%），其次是白来航鸡（雌）×罗德岛红鸡（雄）（10.28%）和纯白来航鸡（9.57%）。(5) 与纯白来航鸡品种相比，纯罗德岛红鸡及其杂交组合中死在壳内且蛋黄在腹腔外的胚胎更多。(6) 使用恒定数量的精子进行人工授精后，白来航鸡的受精率比其他组合维持的时间更长。在受精蛋的基础上，授精一周后的受精率下降速度往往比孵化率更快。(7) 得出的结论是，罗德岛红鸡受精率低两性都有责任，但孵化率低是雌性的责任，而这种不佳表现主要是由于孵化期间蛋重损失更大。
