TUBAL TRANSFER OF BOVINE EMBRYOS - A SIMPLE ENDOSCOPIC METHOD REDUCING LONG-TERM EXPOSURE OF IN-VITRO PRODUCED EMBRYOS

Although numerous trials had shown the need to define a procedure to g et free access to the bovine oviduct, there was no adequate report of a technique which was accepted for the routine transfer of early tubal -stage embryos. We have now report an endoscopically mediated transvag inal method for transferring embryos into the oviduct. The in vitro pr oduced embryos were loaded into a curved glass capillary tube which wa s connected to a perfusor tube plus 1-mL syringe. The capillary tube w as directly inserted via the infundibulum into the ampulla. After firs t having checked the ovaries for the presence of a corpus luteum the e mbryos were deposited under visual guidance in about 20 to 50 mu L med ium. Twenty-four Simmental and Brown Swiss heifers received 26 embryos and 9 animals became pregnant, of which 7 recipients delivered 8 live calves. With practice, the time used for endoscopic transfer was redu ced to less than 10 min. The results demonstrate that the described te chnique is suitable fbr practical application. Especially for the earl y transfer of IVP-derived embryos this technique might be advantageous . In conclusion, this method is also of great potential interest for t he recovery of tubal-stage embryos and for the in vivo culture of embr yos followed by conventional flushing at Day 7. (C) 1998 by Elsevier S cience Inc.