Faculty of Veterinary Medicine, Department of Hygiene and Preventive Medicine, Kafr El-Sheikh University, Kafr El-Sheikh, Egypt.
Vet Q. 2011 Dec;31(4):165-71. doi: 10.1080/01652176.2011.642533. Epub 2011 Dec 12.
Rabbit production in Egypt exhibits a seasonal pattern with much higher yields from September to May. This variation might be explained by reproductive performance as controlled by annual photoperiodicity.
HYPOTHESIS/OBJECTIVES: The aim of this study was to investigate whether the reproductive performance of rabbits can be improved by either increasing the photoperiod or by administering melatonin supplement.
In total 78 White New Zealand rabbits (60 does and 18 bucks) were used during September and October reared in a private Rabbitary in Menuofia Governorate, Egypt. The animals were randomly assigned to six treatment groups of 10 does and three bucks each (8, 10, 12, 14, and 16 h light and melatonin (1 mg/kg BW/day orally for two weeks). Ejaculate traits, sexual activity of bucks, sexual receptivity and reproductive performance of does were recorded.
The results revealed that exposure of rabbits to long photoperiods (14 and 16 h light) or treatment with melatonin improved the quantity and quality of ejaculate traits and buck sexual activity as well as doe's sexual receptivity, feed intake, litter size, weight at birth and time-to-weaning. On the other hand, gestation period and pre-weaning mortality percentage decreased.
Application of long photoperiods is beneficial to rabbit producers and 14 h light combined with 10 h dark is optimal for satisfying the physiological requirements of the rabbits. Finally, from an economic point of view, the light schedules are cheap and easy to apply and can be used as biostimulation instead of melatonin.
埃及的家兔生产具有季节性模式，从 9 月到 5 月产量更高。这种变化可能是由年度光周期性控制的繁殖性能解释的。
假设/目的：本研究旨在探讨通过增加光照时间或给予褪黑素补充是否可以提高兔子的繁殖性能。
在 9 月和 10 月期间，总共使用了 78 只新西兰白兔（60 只母兔和 18 只公兔），在埃及 Menuofia 省的一个私人兔舍中饲养。这些动物被随机分配到六个处理组，每组 10 只母兔和 3 只公兔（8、10、12、14 和 16 小时光照和褪黑素（1mg/kgBW/天，口服两周）。记录精液特征、公兔的性行为、母兔的性接受能力和繁殖性能。
结果表明，兔子暴露在长光照时间（14 和 16 小时光照）或褪黑素治疗下，提高了精液特征和公兔性行为的数量和质量，以及母兔的性接受能力、饲料摄入量、窝产仔数、初生体重和断奶时间。另一方面，妊娠期和断奶前死亡率百分比降低。
应用长光照时间对兔生产者有益，14 小时光照结合 10 小时黑暗是满足兔子生理需求的最佳选择。最后，从经济角度来看，光照时间表便宜且易于应用，可以作为生物刺激剂而不是褪黑素使用。
