Oviductal Function during the Annual Ovarian Cycle of a Wild Avian Species,the Tree Pie Dendrocitta vagabunda

The present investigation was carried out on oviductal activity during the annual ovarian cycle of the Indian tree pie (Dendrocitta vagabunda). The oviductal activity was evaluated by weight, length, histology (gross and quantitative) and peroxidase, acid phosphatase, alkaline phosphatase, sialic acid, glycogen, RNA and protein concentrations of different regions of the oviduct. All these values w ere low during the nonbreeding phase (August to January), increased during the progressive phase (February to March), became maximum during breeding (April to May) and decreased in the regression phase (June to July). The functional change of the oviduct is suggested to be due to fluctuation of ovarian steroid activity in this avian species.