Clinical Efficacy of Whelping Induction Protocol using Mifepristone in Advanced Pregnant Bitches

An efficient and safe protocol for induction of whelping in dogs is an important emerging option in canine reproduction as an alternative to elective/planned caesarean. The aim of the present study was to assess the efficacy and safety of whelping induction in advanced pregnant bitches with oral administration of mifepristone. The study was conducted in 24 bitches in advanced pregnancy usually considered for a planned elective caesarean. These animals were administered mifepristone at the rate of 2.5-3 mg/kg late pregnancy body weight, orally twice daily, at 8 h interval for a single day. The average time taken for induction of whelping was 23.58 + 2.47 (range 8-67) h in 23 bitches which responded positively to the protocol (95.83 % response rate). Within 24 h of initial dose of mifepristone 17 bitches (70.83 %) whelped and within 36 h five more whelped (91.6 %). It was also found that the expulsion phase length in 23 bitches which whelped averaged 3.82 + 0.47 (range 1-10) h and the percentage of still births was 10.8 per cent. The administration of mifepristone in dogs in advanced pregnancy can be considered as a good alternative to surgical management especially when the foetal heart rates are above critical limits and the foetal head diameter does not pose a threat by way of foeto-maternal disproportion so as to prevent a normal whelping after induction.