Morphological aspects by light and scanning electron microscopic studies of swamp buffalo endometrium at follicular and mid-luteal phases.

This study was carried out to observe morphological changes of swamp buffalo endometrium at follicular and mid-luteal phases. Uterine horns were collected from female buffaloes at a local abattoir and the selected estrous stages were categorized into the follicular (n = 10) and mid-luteal (n = 10) phases. General histology and histomorphometry were examined under light microscope (LM) whereas a scanning electron microscope (SEM) was used to study surface epithelial changes. The results showed that the height of the endometrial epithelium, the number of superficial endometrial glands and the number of capillaries were significantly greater (p < 0.05) at the follicular phase. By SEM examination, the ciliated and secretory cells with different patterns, i.e. abundant microvilli on the apical part or secretory protrusion in various degrees, distinctly increased at the follicular phase. In the meantime, numerous secretory cells with stubby microvilli were covered throughout the endometrial surface with secretory vesicles on endometrial glandular orifices at the mid-luteal phase in which the ciliated cells were sparsely seen. It was concluded that the swamp buffalo endometrium obviously revealed modifications during the estrous cycle for physiological events, i.e. sperm transport, early embryonic development and implantation.