Laparoscopic techniques for the recovery and transfer of microinjected goat zygotes

L-OPU in Goat and Sheep-Different Variants of the Oocyte Recovery Method

Simple summary

In this study, minimally invasive laparoscopic methods of recovering oocytes in goat and sheep (L-OPU, laparoscopic ovum pick-up) were developed and improved. Applying the laparoscopic technique allows animal welfare to be significantly improved while still maintaining high effectiveness of the method. The method allows a high number of good quality oocytes to be obtained and additionally reduces the invasiveness of the method and tissue damage which occurs during the operation to a minimum. It requires a short time and allows animals to return to the herd immediately after the operation has been completed. Additionally, it also gives the opportunity for maximum use of the animal’s genetic capability. The limitation of using the L-OPU method in goats is its variable and changing effectiveness. That is why it is crucial to develop an effective and repeatable method. The study compared several variants of the method including varying techniques of conducting the operation, various tools for recovering oocytes, and different plans of hormonal stimulation. As a result, an optimal method of recovering oocytes was developed. The research may be of great importance in improving the welfare of animals and increasing the effectiveness of biotechnological methods used in goat and sheep breeding as well as in the area of research.

Abstract

The laparoscopic method of recovering oocytes in goats and sheep is one of the minimally invasive methods used in the biotechnology of animal reproduction. It allows for good quality oocytes that are suitable for in vitro maturation and fertilization to be recovered. The limitation of using the laparoscopic ovum pick-up (L-OPU) method in goat and sheep is its changing effectiveness and the lack of repeatability of results, as well as the varying effectiveness of different variants of the method. Therefore, it is necessary to develop effective non-invasive techniques allowing for multiple good quality oocyte recovery that would be suitable for in vitro maturation and fertilization. In this study, four different L-OPU variants were described in goats and sheep. Various techniques of recovering oocytes were discussed, including the techniques of conducting the operation, various tools for recovering oocytes, and different plans of hormonal stimulation. Recovery rates were 35% (Variant I), 57% (Variant II), 72% (Variant III), and 67% (Variant IV). After evaluation, 94% (both Variant I and II), 93% (Variant III), and 84% (Variant IV) of the oocytes were qualified for in vitro maturation. The results of the study show that the proposed technique of laparoscopic recovery of oocytes allows a sufficient number of ovarian cells suitable for in vitro culture to be obtained and as a consequence it makes them useful in in vitro maturation/in vitro fertilization (IVM/IVF) programs or cloning. The method allows for a fast and effective conduct of the operation in a living donor with minimal invasiveness while preserving the excellent condition of animals.