149 LAPAROSCOPIC EMBRYO TRANSFER IN PIGS

Abstract

In an effort to optimize the number of live offspring from cloned and transgenic pig embryos, embryos are surgically transferred into the isthmus region of the oviduct soon after micromanipulation. Surgical embryo transfer in pigs is successful but still an invasive process. Laparoscopic embryo transfer (Besenfelder et al. 1997 Theriogenology 47, 1051–1060) is much less invasive than surgery and is more adaptable to a variety of commercial embryo transfer conditions. Our goal was to develop the use the laparoscope as an alternative method of embryo transfer for micromanipulated embryos. Naturally cycling maternal white line donor and recipient females were used for laparoscopic embryo transfer. Donors were selected to be in estrus 0 to 24 h before recipients. Two- to four-cell embryos were surgically recovered via mid-ventral laparotomy and immediately prepared for laparoscopic transfer into the oviduct through the infundibulum or through puncture of the oviduct into the ampulla. Sixty-nine embryos (range, 13–20) were transferred into the oviduct via the infundibulum of four recipients. Two recipients farrowed (50%), one recipient spontaneously aborted on Day 27, and one returned to estrus on Day 25 of the estrous cycle. Twenty-one pigs were born (10.5 pigs/farrowed sow) resulting in 30% (21/69) of transferred embryos becoming live offspring. Ninety-seven embryos (range, 10-21) were transferred into the ampulla of the oviduct of six recipients. Four recipients farrowed (67%) and 2 returned to estrus on Day 20 and Day 28. Thirty-nine pigs were born (9.5/sow farrowed) resulting in 39% (38/97) of transferred embryos becoming live offspring. Observations indicate that it is much easier to find the oviduct and deliver embryos via puncture into the ampulla than find and insert the transfer catheter into the infundibulum. Using the efficiencies generated from these data, 1.1 more pigs can be expected per transfer by transferring embryos to the oviduct via puncture than into the oviduct via the infundibulum. These data demonstrate the effective use of the laparoscope for oviductal embryo transfer. Further work is needed to determine if the laparoscope improves the production of live offspring compared to surgical embryo transfer.