Roque L, Soares M C
Instituto Superior de Agronomia, Lisboa, Portugal.
Poult Sci. 1994 Dec;73(12):1838-45. doi: 10.3382/ps.0731838.
The effects of eggshell quality and breeder age were assessed on egg weight loss during incubation, fertility, hatchability, and embryonic mortality. The trials involved hatching eggs from three commercial broiler breeder flocks of the same strain but of different ages. The eggs were divided according to specific gravity into two groups, thin-shelled (< or = 1.080) and thick-shelled (> 1.080). Thin-shelled eggs displayed a greater increase in weight with breeder age and greater weight loss during incubation. Thick-shelled eggs showed an increased hatchability as a result of greater fertility and lower intermediate and late embryonic mortalities. Percentage of culls, pips, and rots were not related to shell thickness. Eggs from the younger flock had a higher weight loss during incubation irrespective of shell thickness. Hatchability and viability (hatchability of fertile eggs) were lower in the younger flock due to increased early and late embryonic mortalities. Fertility, culls, and pips were not affected by breeder age. The data may indicate the extent to which recent innovations in breeder management and in incubation technology have changed patterns of fertility and embryonic mortality.
评估了蛋壳质量和种鸡年龄对孵化期间蛋重损失、受精率、孵化率和胚胎死亡率的影响。试验涉及来自同一品系但不同年龄的三个商业肉鸡种鸡群的种蛋。根据比重将蛋分为两组，薄壳蛋（≤1.080）和厚壳蛋（>1.080）。薄壳蛋随着种鸡年龄增长重量增加幅度更大，且孵化期间重量损失更大。厚壳蛋由于受精率更高以及中期和后期胚胎死亡率更低，孵化率有所提高。淘汰蛋、啄壳蛋和腐坏蛋的比例与蛋壳厚度无关。无论蛋壳厚度如何，来自较年轻鸡群的蛋在孵化期间重量损失更高。由于早期和后期胚胎死亡率增加，较年轻鸡群的孵化率和存活力（受精蛋的孵化率）较低。受精率、淘汰蛋和啄壳蛋不受种鸡年龄影响。这些数据可能表明种鸡管理和孵化技术方面的最新创新在多大程度上改变了受精率和胚胎死亡率模式。
