Quality and quantity of follicular atresia in the ovaries of Indian buffaloes (Bubalus bubalis)

The present investigation was made on 18 ovaries of adult buffaloes to explore the type and number of atretic Graafian follicles. Histomorphological studies revealed that atretic Graafian follicles constituted 71.77% of the total follicular population. Two types (obliterative and cystic) of atresia was observed in this study On the basis of number of pyknotic nuclei present in the granulosa layer or in the liquor folliculi, obliterative atresia was further categorized as atresia of first degree and atresia of second degree. In cystic type of atresia, granulosa layer was completely atrophied and the theca layer may be luteinized or fibrosed or hyalinized type. The quantity of Graafian follicles accounted 91.17% as cystic and 8.83% as obliterative type. Among obliterative atretic follicles 43.40% comprised of atresia of first degree and 56.60% as atresia of second degree. Of the follicles with cystic atresia, 86.84% comprised of fibrosed, 6.40% of luteinized and 6.76% of hyalinized type. The number of obliterative atretic follicles was maximum in follicular phase and minimum in mid-luteal phase and reverse was true with cystic atresia. It is concluded that higher rate of atresia (> 70%) in Graafian follicles of buffalo may be the reason for low reproductive efficiency of these animals.