Reproductive aspects of Japanese quails (Coturnix cotumix japonica) hatched from eggs incubated under different light colors

The objective of this study was to evaluate the effect of exposure to different colors of light during egg incubation on the reproductive parameters of male and female Japanese quails. A total of 1776 eggs were incubated under four lighting conditions for 24 h a day during the entire incubation period: white LEDs, green LEDs, red LEDs and darkness (control). The experimental design was a randomized block (incubation time) with four treatments of six replicates of two cages each. After hatching, the birds were housed in brood cages with 18 birds each to 35 days of age, when they were sexed and transferred to production cages for evaluation of reproductive parameters. After the onset of laying, the number of eggs in each cage was recorded daily, and the values were used to obtain the age of the females at first egg and at 80% laying. At 35 and 60 days of age, several birds from each cage were euthanized for anatomical and histological evaluation of the gonads. Two females from each cage were weighed every three days until 60 days of age to determine the growth curve. After 60 days, eggs from each cage were collected and assessed for external and internal quality. At 70, 74 and 78 days of age, semen collection was performed and seminal quality was evaluated. Then, the males were transferred to cages containing 9 females for the fertility test. Hatchability was higher (P < 0.05) in eggs incubated in the dark and under the red LED. The age of maximum growth was higher (P < 0.05) in birds from eggs incubated in the dark and under the white LED. There was no difference (P> 0.05) in the anatomical and histological characteristics of the testicles between the groups incubated under different light colors, except for the diameter of the seminiferous tubules, which was greater (P = 0.05) in the dark and in the white LED groups. There was no effect (P > 0.05) of light color during incubation on the productive index or egg quality of adult birds. There was also no effect (P > 0.05) on sperm quality, except for sperm motility, the values of which were higher (P < 0.05) in birds from eggs incubated in different colors of light. However, this difference was not sufficient to significantly (P > 0.05) influence bird fertility. It is concluded that under the studied conditions, the incubation of quail eggs under white, red, and green LED lamps does not influence the reproductive characteristics of the quails. (C) 2021 Elsevier Inc. All rights reserved.