Effects of ethinylestradiol and danazol on embryo survival and implantation in mated beagle bitches.

Eleven mature Beagle bitches were artificially inseminated and then used to determine the effects of ethinylestradiol or danazol on nidation, embryo survival and maintenance of pregnancy. The dogs were grouped so that three were kept as controls, four others were treated with ethinylestradiol and the remaining four were treated with danazol. The compounds were administered orally at varying intervals after insemination. The effects of the compounds were deduced from the condition of the ovaries and uterus examined at laparotomy, and the results of whelping. Ethinylestradiol had minimal effect on embryo development and implantation. Three of four bitches treated with ethinylestradiol whelped. Similarly, danazol treatment had little or no effect on embryonic survival and implantation. It is concluded that, ethinylestradiol or danazol at the dosages and schedules used in this study did not significantly interfere with embryonic survival or implantation in pregnant Beagle bitches.