Divergent cloacal gland photo-responsiveness in male Japanese quail exposed to short days and associated differences in social interactions and reproduction

Abstract

Quail under short d (SD) reduce their gonadal development, and consequently their cloacal gland (CG) size, aggressiveness, sexual behaviors, and reproductive performance. However, some quail appear nonresponsive to SD inhibition. When male quail were arbitrarily classified according to their CG involution during maximum photoinhibition (5 wk after SD exposure) as either nonresponsive (NR-SD) or responsive (R-SD), NR-SD quail showed intermediate CG volume between R-SD quail and the control quail kept on long d (C-LD). Herein, we evaluate whether NR-SD and R-SD male Japanese quail differ in their social interactions and reproductive performance while under SD; C-LD males were used as fully reproductive control. First, we assessed over 4 consecutive d, brief (5-min) home cage encounters between individually housed C-LD, NR-SD, or R-SD males and an unfamiliar C-LD male visitor. To determine male reproductive capacity, the following wk, males received the visit (10-min) of a mature female over 3 consecutive days. C-LD, NR-SD, and R-SD resident males showed higher aggressiveness than their photostimulated male visitors, respectively, in 100, 64, and 0% of the studied cases and were also able to, respectively, fertilize 100, 100, and 15% of their female visitors. Second, male-female encounters were again repeated 4 wk later to further assess reproductive performance and behavior. Naive C-LD, NR-SD, and R-SD males also were evaluated to assess potential consequences of the previous male-male interactions on the later performance. The number of males performing aggressive pecks towards females showed a C-LD>NR-SD>R-SD pattern. While mounts, CG contacts, and reproductive capacity showed a C-LD = NR-SD>R-SD pattern, copulatory efficiency exhibited an NR-SD>C-LD = R-SD pattern. Sexual behaviors were not modulated by previous male-male brief social interactions. Findings suggest that NR-SD males are able to breed similarly to their C-LD counterparts, which could be considered an indicator of a reduced reproductive dependence on seasonal photoperiod cues. Differences in the expression of aggressions between NR-SD and C-LD males may underlie the observed NR-SD improved copulatory efficiency when interacting with females.

The relevance of a right scale for sampling when studying high-resolution behavioral dynamics

“…Herein we show that the 0.5s – 6 min sampling interval used previously to assess the temporal dynamics of behavior in small animals 18 , 27 – 31 including Japanese quail 11 – 13 , 31 , 32 is insufficient to capture the most frequent event durations. Many of the behaviors studied showed that the most probable event durations lied between 60 and 300 ms (Supplementary Tables S2 and S3 ).…”

High-resolution behavioral time series of Japanese quail within their social environment

“…Birds that performed more than 5 aggressiveness behaviors were considered aggressive, and birds that did not perform any aggressive behavior towards the photocastrated opponent were considered non-aggressive 58 . If during the interaction a quail received more than 5 consecutive aggressive pecks, showed a clear and continued escaping (retrieval) behavior, and/or showed any sign of physical damage, the interaction was immediately interrupted 65 . Caliva et al .…”

Dietary ascorbic acid and betaine improve stress responses, testosterone levels and some sexual traits in male Japanese quails during the dry season

“…Cloacal gland is a peculiar anatomical feature of Coturnix quails which is an indication of testicular size and function. Therefore, the assessment of cloacal gland size is referred to as a noninvasive tool to evaluate testicular activity and maturity in Japanese quails (Dominchin et al, 2016(Dominchin et al, , 2017. Momoh et al, (2014) showed that the age of sexual maturity in Japanese quails reared under hot-humid condition is 5-6 weeks old.…”