RESUMEN
This study aimed to investigate the relationship between histomorphological appearance of granulosa cells and oocytes recovered from follicles in relation to the presence of corpora lutea. The ovaries were collected at a local slaughterhouse from 22 buffalo-cows whose reproductive organs showed no macroscopic abnormality. Out of 35 visible follicles [>/10 mm in diameter] dissected, 24 follicles were on ovaries bearing corpora lutea [CLO] and 11 follicles were on ovaries non bearing corpora lutea [NCLO]. The follicular contents were separately aspirated and examined for the quality of oocyte recovered. The follicular walls were dissected and prepared for the light and electron microscopic examination. Fourteen oocytes were recovered from 35 follicles. Only 33.3% of oocytes recovered from follicles on CLO compared with 80% of oocytes recovered from follicles on follicles on NCLO classified as intact oocytes. Light microscopic observations of granulosa cells of these follicles [nineteen follicles on CLO and eight follicles on NCLO] showed that sixteen follicles on CLO and only one follicle on NCLO were atretic. Ultrastructural observation of granulosa cells revealed different degrees of cell affection in granulosa cells of follicles on CLO. This affection included dilatation and fragmentation of the rough endoplasmic reticulum together with the appearance of numerous lysosomes and fat droplets. The nuclei were electron dense, irregular and eccentric. Thus, it was concluded that most of visible follicles [>/ 10 mm in diameter] on ovaries bearing corpora lutea [middle of estrous cycle] showed many degenerative changes and most of oocytes recovered from these follicles were denuded