Abstract
The morphological characters of ovaries were studied in 51 slaughtered pregnant Egyptian buffaloes including the weight and diameter of corpora lutea and the number and size of healthy follicles. Progesterone and estradiol-17 beta concentrations were estimated in both peripheral plasma and feces using enzymimmunoassay. The results revealed a decrease in number of all sized follicles as pregnancy advanced. Plasma and fecal progesterone concentrations increased and plasma estradiol-17 beta levels decreased with the progress of pregnancy. Positive correlation coefficients existed between the ovarian weight and weight of corpora lutea on one hand and between the number of follicles and estradiol-17 beta levels on the other. The correlation coefficients between the weight of corpora lutea and estradiol-17 beta levels were negative. Seasonal differences in ovarian activity occurredn pregnant buffaloes coinciding with the profound effect of season on the progesterone and estradiol-17 beta concentrations in the peripheral plasma.