Estrus Induction in Female Dogs
The induction of estrus in bitches (female dogs) refers to the artificial stimulation of the reproductive cycle in female dogs.
Monitoring the Bitch
Regardless of the method chosen for estrus induction, vaginal cytology should be obtained on an alternate-day basis.
It is recommended that natural breeding or artificial insemination begin when superficial cells compose 60% or more of the exfoliated vaginal epithelial cells and/or when plasma progesterone concentrations exceed 1 ng/ml.
Insemination should continue on an alternate-day basis until diestrus is confirmed.
Use of PMSG or FSH
PMSG
Bitches ovulated following 9 consecutive days of IM or subcutaneous PMSG, injected at 44 IU/kg /day followed by 500 IU of hCG IM on day 10. Animals exhibited behavioral estrus 10 to 15 days after initiating treatment.
Pregnant mare serum was administered to mature anestrus bitches for 10 consecutive days at subcutaneous does of 500 IU /day. 250 IU/day, or 20 IU/kg/day. This was followed by a subcutaneous injection of 500IU of human chorionic gonadotropin on day 10. Those side effects included thrombocytopenia, uterine disease, and termination of pregnancy.
FSH with or without Estrogen Priming
Diethyl stillbesterol as 5 mg daily for 7 days.
Gondadotropin Releasing Hormone or a GnRH Agonist
A protocol used subcutaneous injections of a GnRH agonist at a dose of 1 pg/kg TID for 11 days and then 0.5 pg/mg TID for 3 days.
Dopamine Agonist Administration
Two dopamine agonist treatments reported to be effective have included:
- Bromocriptine at 0.05.or 0.1 mg/kg, PO, QD. or BID;
- Cabergoline at 5 ug/kg, PO, QD;
Administration is until an induced proestrus is pronounced for 2 days or until the onset of estrus.
