Effect of sectioning on the number of isolated ovine preantral follicles.

The aim of the present study was to test the effect of the interval of serial sections in the tissue chopper on the number of isolated ovine preantral follicles. Best results were obtained when the ovarian fragments were cut in the tissue chopper at interval of 87.5µm (1592 preantral follicles per treatment). Histochemical analysis showed that the follicular morphology was preserved after mechanical isolation as demonstrated by the normality of oocytes and granulosa cells as well as by preservation of basement membrane. The percentages of isolated primordial, primary and secondary follicles were 92, 6, and 2%, respectively. The follicular sizes varied from 12.5 to 96.3µm in diameter. In conclusion, a greater number of isolated preantral follicles were obtained when the method of isolation used the tissue chopper adjusted at 87.5µm. Besides, this treatment does not affect the follicular integrity after the isolation procedure.