Evaluation of saline and coconut water solutions in the preservation of sheep preantral follicles in situ

Abstract

This efficiency of saline and coconut water solutions in the preservation of sheep preantral follicles in situ at different temperatures and incubation periods was investigated. At the slaughterhouse, each pair of ovaries was divided into 19 fragments. One ovarian fragment was immediately fixed for histology (control time zero). The other 18 ovarian fragments were randomly distributed in tubes containing 2 ml of saline or coconut water solutions at 4, 20 or 39 °C and then stored for 4, 12 or 24 h. Histological analysis showed that the storage of ovarian fragments in saline solution at 20 °C for 12 and 24 h, in coconut water solution at 20 °C for 24 h and in both solutions at 39 °C reduced ( P<0.05) the percentage of morphologically normal preantral follicles (MNPFs) when compared with the control. In contrast, the preservation at 4 °C in all incubation times and at 20 °C for 4 h, in both solutions, kept the percentage of MNPF similar to control values. There was a significant predominance of type 1 (only oocyte degeneration) and type 2 (oocyte and granulosa degeneration) degenerated follicles, respectively, in the fragments stored at 20 and 39 °C in both solutions. In conclusion, this study shows that sheep preantral follicles can be preserved in situ at low temperatures in saline or coconut water solutions.