Megestrol acetate for estrus postponement in the bitch.
Megestrol acetate was given orally to 389 bitches in early proestrus, at a dosage of 2.2 mg/kg (1 mg/lb) per day for 8 days. Estrus was suppressed in 357 (92%) of the bitches. Additionally, 119 bitches in anestrus were given the drug at the rate of 0.55 mg/kg (0.25 mg/lb) per day for 32 days. Estrus was suppressed in 115 (98%) of these bitches. Adverse effects were minimal. Pyometra developed in 3 (0.8%) of the 389 bitches treated in early proestrus. The drug also was given to 19 bitches at the rate of 0.55 mg/kg/day for 32 days, regardless of the stage ofting at the 1st posttreatment estrus and 4 after mating at the 2nd posttreatment estrus. Litter size, success in rearing pups, and sex ratios were not significantly different from these factors in 53 litters from untreated bitches.
D000284:Administration, Oral; D000818:Animals; D002369:Castration / Q000662:veterinary; D004283:Dog Diseases / Q000139:chemically induced; D004285:Dogs / Q000502:physiology*; D004716:Endometritis / Q000139:chemically induced / Q000662:veterinary; D004971:Estrus / Q000187:drug effects*; D005260:Female; D005306:Fertilization / Q000187:drug effects; D007044:Hysterectomy / Q000662:veterinary; D008098:Litter Size / Q000187:drug effects; D008535:Megestrol / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D011247:Pregnancy; D011359:Proestrus / Q000187:drug effects; D012744:Sex Ratio
D008535:Megestrol