Divergent cloacal gland responses to short days in Japanese quail and short-term related consequences on social behavior and reproduction

DOMINCHIN MF; BUSSO JM; GUZMÁN, DA; KEMBRO JM; MARIN RH

Louisville, Kentucky

Congreso; Poultry science Association 104 th Annual meeting; 2015

Poultry Science Associaion

Exposure to short day photoperiod (SD) in Japanese quail reduced gonadal development, and consequently, their cloacal gland (CG) size, reproductive capacity and aggressive behaviors. Interestingly, not all quail fully responded to SD inhibition with some birds even showing no CG response. In a previous work, quail in SD were arbitrarily classified by their divergent CG development as either responsive (R) or nonresponsive (NR), with NR males showing on average intermediate CG and testosterone values between R and long day photoperiod reared males (LD). Herein we evaluated whether R and NR males differ in social interactions and reproductive potential while under SD. LD males were used as controls with full reproductive capacity. ANOVAs, X2 observed vs. expected and proportion tests were used to detect differences at P less than 0.05. Firstly, during peak photoinhibition (5wk after SP exposure) we assessed male-male aggressive interactions determining winners and losers. Individually-caged R, NR and LD residents received 5-min LD male intruder visits along 4 consecutive days. Next wk, same males received 10-min visits from a LD female partner along 3 days to determine whether those males could fertilize them. Male interactions showed that LD, NR and R residents respectively won 100, 64 and 0% of the fights and were able to fecundate 100, 100 and 17% of the females. Then, male-female encounters were again repeated 4 wk later to assess whether previous social interactions could modulate later reproductive performances during an initial photorefraction stage. Naive R, NR and LD male residents were used as controls. Mounts, CG contacts, and fertility showed an R less than NR = LD pattern. Copulatory efficiency (CE) was found higher in NR compared to R and LP quail. No effects of previous social interactions were detected. Findings suggest that while on SD, NR males are able to breed similarly to their LD counterparts regardless of the outcome of a previous social interaction. Potential differences in the expression of aggression between NR and LD males may underlie the observed differences in CE.