Postnatal development of the oviduct in the Japanese quail (Coturnix coturnix japonica)

Abstract

The structure and postnatal development of the oviduct in quails were investigated using 72 birds aged from day-old to 60 days. The growth, morphology and histology of the oviduct were studied using six birds at each age group.

In the day-old quail chick, the oviduct could seen as a narrow white translucent tube towards the left side of the coelom connected by dorsal and ventral ligaments. The sign of coiling was evident from 25 days of age. In the initial stages, the increase in weight and length of oviduct was in accordance with the growth of the bird. Rapid changes in the development of the organ occurred between 30 and 40 days of age and a sprut in growth was noticed from 40-60 days of age.

In the day-old chick, the cranial regions of the oviduct corresponding to the infundibulum, magnum and isthmus were undifferentiated. Throughout the length of the oviduct, histological appearance was the same. The mucosa was thrown into low primary folds lined by simple columnar epithelium and there was subepithelial connective tissue containing densely packed cells with fine collagen and reticular fibres. The large number of luminal epithelial cells and the increase in height of the mucosal folds indicated entry into a rapid growth phase which started between 30 and 40 days of age.

In the adult bird, the innermost epithelium of the different segments of the oviduct consisted of ciliated columnar cells and secretary goblet cells. Lamina propria was packed with tabular glands except in the funnel of infundibulum, magnum-isthumas junction and vagina. Bundles of collagen and a few elastic and reticular fibres constituted the core of the mucosal folds. Mucosal folds also contained lymphocytes in diffuse form and nodular aggregates. Thickness of the tunica muscularis increased from the anterior to the posterior end of the oviduct. Externally there was a typical serosa.

Mucosal ridges of the thin walled funnel of the infundibulum were narrow and at the bases of these ridges were the glandular grooves. Tunica muscularis consisted of circularly arranged fibres and scattered bundles. Within the neck of the infundibulum, height of the mucosal ridges was more. Lining cells of the tubular glands showed PAS +ve reaction. Magnum was the longest and most coiled component of the oviduct, the wall of which was thicker due to the greatest development of tubular glands. Mucosal ridges of the isthumus were angular in appearance. Apex of the lining epithelium presented glycogen granules. Tunica muscularis consisted of inner circular and outer poorly developed longitudinal smooth muscle separated by loose connective tissue and blood vessels.

Uterus was wider and thinner than the cranial portions in day-old bird itself. Secondary mucosal folds and scattered muscle fibres could be noticed at 15 days of age. In the adult bird, mucosal was thrown into numerous long, flat, discontinuous, spatula – shaped folds lined by alternating spical and basal cells. Lamina propria was loosely packed with tubular glands. Tunica muscularis was better developed with inner circular and irregular bundles and outer longitudinal muscle layer. Ultero – vaginal junction was characterized by the presence of sperm – host glands. In the vagina, mucosal folds were narrow and regular. Lining epithelium was higher . Musculature was thickest in this region. Acid and alkaline phosphatase activities were detected throughout the oviduct, the greatest activity being in the uterine region.