The Effects of Medroxyprogesterone Acetate and Ethinylestradiol on Hemogram, Prostate, Testes, and Semen Quality in Normal Dogs

Abstract

Three dogs were treated with medroxyprogesterone acetate (MPA) and three were treated with ethinylestradiol. The results indicate that at a dosage of 3-4.8 mg/kg b.w. MPA does not have any detrimental effects on hemogram, testicles or semen quality, whereas ethinylestradiol (2 micrograms/kg b.w./day) can negatively affect both testes and semen quality. Both drugs can cause a decrease in prostatic size in clinically healthy dogs. Measurements of peripheral serum testosterone levels indicate that at the dosages used, testosterone levels are depressed considerably more by ethinylestradiol than by MPA.