Non-invasive assessment of social interaction effects on the adrenal and gonadal endocrine activity during photorefraction in male Japanese quail exposed to short days

DOMINCHIN MF; PALME R; MARIN RH; BUSSO JM

Berlín

Conferencia; 10th International Conference on Behaviour, Physiology and Genetics of wildlife; 2015

Leibniz Institute for Zoo and Wildlife Research

Temporal dynamic of testicular endocrine activity wasdescribed in Japanese quail when birds exhibit spontaneous cloacal glandrecovery (photorefractoriness) during short days. The observed pattern was alsoassociated with changes in adrenocortical responses. We predicted that quailkept on long day and those non-responsive to short day photoinhibition (LD and SD-NRquail, respectively) will show similar reproductive potential. Indeed, LD andSD-NR showed a similarly higher fertility than their SD-R counterparts after 6weeks exposure to short days. However, it remains unclear whether social cues affectthe dynamic of endocrine adrenal and testicular responses during onset ofphotorefraction. Herein, 54  male quail(10 week of age) exposed to long days were switched to short days (8L:16D).Another group of males was kept under long days as controls (n = 17).After 5 week of SD exposure, quail were classified as either non-responsive (SD-NR;n=21) or responsive (SD-R; n=33) to photoperiod, depending on cloacal glandvolume and foam production (Dominchin et al., 2014). At 15 wk of age, individually-cagedLD, SD-NR and SD-R residents received 5-min of photostimulated male intrudervisits along 4 consecutive days (social treatment). Since 14 wk of age andduring a 6-wk period, droppings were bi-weekly collected to measurecorticosterone (CM) and androgen metabolites (AM). Cloacal gland volume (CGV)was also registered. Repeated measure ANOVA detected an interaction betweenphotoperiod and week of age (P < 0.001) and no effect of social treatment. Asexpected, at 14 wk of age assessment showed LD > SD-NR > SD-R pattern inCM, AM and CGV values. At 16 weeks of age SD-NR and SD-R started showing asignificant increase of CGV, CM and AM values. At this time, SD-NR CM levelsreached the values observed in the LD males. The CM pattern (LD=SD-NR>SD-R) persistedup to the end of the study. AM level reached a similar LD=SD-NR>SD-R patternonly at the end of the study. Results suggest that short and repetitive social encountersare not able to affect spontaneous cloacal gland recovery and endocrineactivities during onset of photorefractoriness. Thus, an opportunistic socialinteraction immediately after peak of photo-inhibition (winter) appeared not enoughto modulate the time of breeding in male Japanese quail.