Yadav Suneeta, Chaturvedi Chandra Mohini
Department of Zoology, Banaras Hindu University, Varanasi 221 005, India.
Physiol Behav. 2015 Aug 1;147:163-8. doi: 10.1016/j.physbeh.2015.04.036. Epub 2015 Apr 23.
An extensive literature is available on the photoperiodic responses of avian species but studies on light colour and wavelength from light emitting diode (LED) sources on reproduction are limited. Hence, an experiment was designed to study the effect of different colours and intensities of light on the reproductive responses of Japanese quail. Three-week old quail were exposed to five different light conditions with a long photoperiod (LD 16:8): WT (white fluorescent light 100 lux as control), W LED (white light emitting diode, 30 lux), B LED (blue LED, 30 lux), G LED (green LED, 30 lux) and R-LED (red LED, 30 lux). The cloacal gland size, an indicator of androgenic activity, was monitored weekly. The results indicated an early initiation of gonadal growth in WT quail which continued and maintained a plateau throughout the period of study. On the other hand, in general low intensity light, there was a decreased amplitude of the reproductive cycle and the quail exposed to different colour lights (green, red and blue lights) used different incubation times to initiate their gonadal growth and exhibited a gonadal cycle of a different duration up to 15.5 weeks. Thereafter, the gonad of quail of all the LED groups started developing again (including the blue LED exposed quail which remained undeveloped until this age) and attained the increased degree of growth until 26.5 weeks of age. During the second cycle, gonads of green and red light exposed quail continued to increase and maintained a plateau of development similar to WT exposed control while white and blue LED exposed quail exhibited spontaneous regression and attained complete sexual quiescence. Based on our study, it is suggested that long term exposure to blue LED light of low intensity may induce gonadal regression even under long-day conditions (LD 16:8), while exposure to green and red lights appears to maintain a constant photosensitivity after one complete gonadal cycle.
关于鸟类的光周期反应已有大量文献，但关于发光二极管（LED）光源的光颜色和波长对繁殖影响的研究却很有限。因此，设计了一项实验来研究不同颜色和强度的光对日本鹌鹑繁殖反应的影响。将三周龄的鹌鹑置于长光周期（LD 16:8）的五种不同光照条件下：WT（白色荧光灯，100勒克斯作为对照）、W LED（白色发光二极管，30勒克斯）、B LED（蓝色发光二极管，30勒克斯）、G LED（绿色发光二极管，30勒克斯）和R - LED（红色发光二极管，30勒克斯）。每周监测泄殖腔腺大小，这是雄激素活性的一个指标。结果表明，WT组鹌鹑性腺生长提前开始，并在整个研究期间持续且维持在一个稳定水平。另一方面，在一般低强度光照下，繁殖周期的幅度减小，暴露于不同颜色光（绿色、红色和蓝色光）下的鹌鹑开始性腺生长的孵化时间不同，并且性腺周期持续时间不同，长达15.5周。此后，所有LED组鹌鹑的性腺再次开始发育（包括直到这个年龄一直未发育的蓝色LED组鹌鹑），并在26.5周龄时达到生长程度增加。在第二个周期中，暴露于绿色和红色光下的鹌鹑性腺持续增大，并维持与暴露于WT组对照相似的发育稳定水平，而暴露于白色和蓝色LED下的鹌鹑则出现自发退化并达到完全性静止。基于我们的研究，建议即使在长日照条件（LD 16:8）下，长期暴露于低强度蓝色LED光可能会诱导性腺退化，而暴露于绿色和红色光下在一个完整的性腺周期后似乎能保持恒定的光敏性。
