Effect of oocyte harvesting techniques on in vitro maturation and in vitrofertilization in sheep

Three different methods, viz., puncture, aspiration and slicing were used f or harvesting the oocytes of ovine ovaries. The aim was to determine an eff icient method for oocyte harvesting and its effect on subsequent in vitro m aturation and in vitro fertilization. The average total number of oocytes r ecovered per ovary was significantly higher by puncture (9.5 +/- 0.45) and slicing (9.5 +/- 0.40) than by the aspiration method (6.8 +/- 0.30) (P < 0. 05). However, the percentage of good quality oocytes was higher in the aspi ration method (64.4%), compared to the puncture (54.7%) or slicing (54.3%) methods. The oocytes obtained were matured and fertilized in vitro using th e spermatozoa collected from the epididymus of slaughtered rams. There was no significant difference in the subsequent percentage of oocytes maturing and bring fertilized in vitro between the three methods of oocyte harvestin g. It can be concluded that all the three methods can be used for the colle ction of oocytes in sheep, without any detrimental effect on the subsequent maturation and fertilization rate. Also the spermatozoa collected from the epididymus of dead/slaughtered rams can be used successfully for the in vi tro fertilization of oocytes in sheep. (C) 2000 Published by Elsevier Scien ce B.V. All rights reserved.