This study aimed to assess the effects of breeder age on egg quality and amino acid and mineral transfer to the egg yolk and yolk sac of newly hatched chicks. Three ages (32, 42 and 52 weeks) of the same commercial flock of Hubbard breeders were studied. A total of 465 eggs were used for each age, with 60 being used for determining egg quality and amino acid and mineral content of yolk, and 405 for incubation period to obtain and evaluate the yolk sac of chicks. Breeders aged 52 weeks had heavier eggs and a higher percentage of yolk (p < 0.05), whereas 32-week-old breeders had higher eggshell percentage and thickness (p < 0.05). The percentage of protein deposited in egg yolk for 52-week-old breeders was higher than that for 32- and 42-week-old breeders (p < 0.05). Percentages of methionine, cysteine, met + cysteine, lysine, threonine, tryptophan, arginine and isoleucine in egg yolk for 32-week-old breeders were higher than that for 42- and 52-week-old breeders (p < 0.05). The transfer from breeder of phosphorus, potassium, calcium, magnesium, copper, iron, manganese and zinc to the yolk of eggs from 32-week-old breeders was greater than that for eggs from 42- and 52-week-old breeders (p < 0.05). Chicks from 32-week-old breeders had greater deposition of phosphorus and calcium in the yolk sac (p < 0.05). Breeder age did not affect the deposition of potassium, magnesium, copper, iron, manganese and zinc in the yolk sac of newly hatch chicks (p > 0.05). It can, however, be concluded that younger breeders deposit more amino acids and minerals in egg yolk, while embryos of older breeders seem to use the nutrients present in the yolk more efficiently during embryonic development.

中文翻译：

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氨基酸和矿物质向蛋黄及其后代卵黄囊的转移受种鸡年龄的影响

本研究旨在评估种鸡年龄对鸡蛋质量以及氨基酸和矿物质向新孵化雏鸡蛋黄和蛋黄囊转移的影响。对同一商业哈伯德种鸡群的三个年龄（32、42 和 52 周）进行了研究。每个年龄总共使用465个鸡蛋，其中60个用于确定鸡蛋质量和蛋黄的氨基酸和矿物质含量，405个用于孵化期以获得和评估雏鸡的卵黄囊。52 周龄种鸡的鸡蛋更重，蛋黄百分比更高（p  < 0.05），而 32 周龄种鸡的蛋壳百分比和厚度更高（p  < 0.05）。52 周龄种鸡的蛋黄中沉积蛋白质的百分比高于 32 周龄和 42 周龄种鸡（p < 0.05)。32周龄种鸡蛋黄中蛋氨酸、半胱氨酸、met+半胱氨酸、赖氨酸、苏氨酸、色氨酸、精氨酸和异亮氨酸的百分比高于42周龄和52周龄种鸡（p  < 0.05）。磷、钾、钙、镁、铜、铁、锰和锌从种鸡到 32 周龄种鸡蛋黄的转移大于 42 周龄和 52 周龄种鸡的蛋黄（p  < 0.05)。32 周龄种鸡的雏鸡卵黄囊中磷和钙沉积较多（p  < 0.05）。种鸡年龄不影响初孵雏鸡卵黄囊中钾、镁、铜、铁、锰和锌的沉积（p > 0.05)。然而，可以得出结论，年轻的育种者在蛋黄中沉积更多的氨基酸和矿物质，而年长的育种者的胚胎似乎在胚胎发育过程中更有效地利用了蛋黄中的营养物质。