Abstract: This article was conducted to study the factors of isolation buffalo small antral follicles,so that to establish the effective isolation method of buffalo small antral follicles. The results showed that the method of mechanical combine with enzyme harvested significantly more small antral follicles (5.64) than mechanical method (3.12,P＜0.05). The average number of small antral follicles harvested from ovary was increased as enhancing the digesting time of enzyme,and the groups of 12 min and 15 min were significantly higher than that of digesting for 5 and 10 min(P＜0.05),but when digesting time of enzyme was prolonged to 20 min,the theca of follicles was broken out that could not isolate the intact small antral follicles. Most small antral follicles harvested from ovary which surface had less than 2 mm follicles but no corpora luteum significantly higher than that of ovary which surface had corpora luteum but no follicles(7.50 and 2.25,P＜0.05). These results indicated that selecting the ovary which surface had less than 2 mm follicles but no corpora luteum and adopting the method of mechanical combine with enzyme to digest 12 to 15 min was fit for isolating the buffalo small antral follicles.

Key words: buffalo; small antral follicles; isolation