Abstract
The female reproductive cycle was investigated in the Indian Tree Pie (Dendrocitta vagabunda) by studying the ovary once a month throughout the year. The ovarian activity showed a distinct annual cycle consisting of four phases: nonbreeding (August to January); progressive (February and March); breeding (April and May); and regression (June and July). The weight of the ovary and diameter of the largest follicle were smallest during the nonbreeding phase, partially increased during the progressive phase, peaked during breeding and decreased thereafter. The primordial and small developing follicles were present in the ovary throughout the year but large developing follicles appeared during April, May and June. Yolky and post-ovulatory follicles were found only during the breeding phase. The population of primordial follicles declined, followed by a rise in the population of small and large developing follicles with the appearance of yolky follicles, during the breeding phase as compared to those of other phases of the cycle. Cholesterol and ascorbic acid concentrations were highest during the nonbreeding phase, slightly declined during the progressive phase, became lowest during breeding and began to rise subsequently. But acid phosphatase, alkaline phosphatase, sialic acid, glycogen, RNA and protein levels were reversely altered. The findings indicate that the ovarian folliculogenesis as well as steroidal activity vary simultaneously with a peak in May during the breeding phase of the seasonal sexual cycle of the tree pie.
