Environmental factors and annual harderian-pineal-gonadal interrelationship in Indian jungle bush quail, Perdicula asiatica.

A functional link between the Harderian and pineal glands has been suspected because they both are known to respond to changes in photoperiod. Further, the pineal gland is known to influence reproduction by secreting melatonin, and melatonin receptors have been detected in the Harderian gland. Hence, we conducted a study to investigate the annual changes in weight and secretory activity for the pineal gland, Harderian gland, and ovary in jungle bush quail (Perdicula asiatica), a bird indigenous to the tropics in India. Annual changes in weight for the three glands were found. In late May, when weather is favorable, the ovary and Harderian gland reached maximal mass, and the pineal gland had the smallest mass. In general, the annual changes in weight for the three glands were associated with the annual changes in melatonin and 17 beta-estradiol concentrations in the plasma and porphyrin content in the Harderian gland. These results suggest that there is an inverse relationship between pineal gland activity and ovarian and Harderian gland activities.