Advances in the production and propagation of transgenic goats using laparoscopic ovum pick-up and in vitro embryo production technologies.

Laparoscopic ovum pick-up (LOPU) is a convenient methodology by which oocytes can be recovered and used either for in vitro production of zygotes or as a source of cytoplasts in nuclear transfer (NT) procedures. The pregnancy and transgenesis rates achieved with IVM/IVF of LOPU-sourced oocytes followed by subsequent DNA microinjection of zygotes are similar to the rates obtained when using in vivo-produced oocytes or zygotes. Similarly, pregnancy rates and kids born by using LOPU-sourced and in vitro matured oocytes as recipient cytoplasts in NT programs are comparable with those reported by others using in vivo matured oocytes collected by oviduct flushing. The use of LOPU allows for improved control over the stage of maturation/development of the oocytes and produced zygotes, a less invasive means of recovery, thereby allowing for repeated usage of the oocyte donor animals and the ability to source the oocytes from live animals of known health status. In addition, because of large follicular responses that can be obtained from prepubertal animals, LOPU followed by IVM/IVF has demonstrated great potential for the early propagation of valuable animals, in particular, transgenic animals.