小型蛋鸡及其杂交种蛋高海拔孵化性能研究

【目的】观察小型蛋鸡及其与藏鸡杂交种蛋在西藏不同海拔地区的孵化性能，分析高海拔胚胎死亡率、种蛋失水率和孵化率。【方法】在海拔2 900m（西藏林芝）和3 650m（西藏拉萨）分别对小型蛋鸡（M）、西藏饲养的小型蛋鸡（MT）、藏鸡×小型蛋鸡（TM）和藏鸡（T）种蛋进行孵化。【结果】在2 900m海拔时M孵化率可达49.44%；MT蛋孵化失水率比M未减少，但孵化率略有提高；TM孵化率高达74.69%；在3 650m海拔，各组胚胎死亡率增加、孵化率下降、雏鸡重/蛋重比值减小；T孵化率也只有30.70%，M孵化率更低，只有10%左右。【结论】小型蛋鸡在高海拔孵化时，种蛋失水率高，孵化率低，但藏鸡与小型蛋鸡杂交种蛋孵化性能表现明显的杂种优势。

Hatchability of Miniature Laying Chicken and Its Hybrids at High Altitude

【Objective】The hatchability of Miniature Layers and hybrids was investigated and the differences of embryonic, mortality, the ratio of egg water loss, and hatchability at different altitudes were analyzed.【Method】Eggs from four groups of chickens, Miniature Layers (M), Miniature Layers fed in Tibet (MT), Tibetan × Miniature Layers (TM), and Tibetan (T), were incubated at 2 900 m an altitude of 2 900 m (Linzhi, Tibet) and an altitude of 3650 m (Lhasa, Tibet), and their embryonic mortality, water loss and hatchability were measured. 【Result】The hatchability of M and TM at an altitude of 2 900 m was 49.44% and 74.69%, respectively. Although it was fed in high altitude environment, MT did not decrease in water loss, and increased a little in hatchability, as compared with M. At 3 650 m an altitude of 3 650 m the embryonic mortalities of all groups increased, and the hatchabilities and ratios of hatch weight to egg weight decreased; and the hatchability of T was 30.70% while that of M was about 10%. 【Conclusion】The results indicated that the water loss was high, and the hatchability of Miniature Layer was low at high altitude, but the heterosis of hatchability of crosbred of T×M was significant.