The effect of hormone treatments (hCG and cloprostenol) and season on the incidence of hemorrhagic anovulatory follicles in the mare: a field study.
The association between use of hormone treatments to induce estrus and ovulation and the incidence of hemorrhagic anovulatory follicles (HAFs) was studied in a mixed population of mares (Equus caballus) during two breeding seasons in a commercial breeding clinic. Mares treated with cloprostenol (CLO) were more likely to develop HAFs than were mares with spontaneous cycles (P<0.001) or those treated with human chorionic gonadotropin alone (P=0.08). There was no significant effect of season on the incidence of HAFs. The mean (+/-SEM) interval from CLO treatment to beginning of HAF development was 6.1+/-0.5 d. Age of mares with HAF cycles was not different (12+/-1.3 yr; P>0.05) from that of mares with ovulatory cycles (10.5+/-1.5 yr).
Eliza Park Stud, Kerrie, Victoria, Australia. copicuervo@hotmail.com
J
J
Cuervo-Arango
J R
JR
Newcombe
D000818:Animals; D000858:Anovulation / Q000150:complications / Q000453:epidemiology* / Q000209:etiology; D006063:Chorionic Gonadotropin / Q000494:pharmacology / Q000627:therapeutic use*; D003008:Cloprostenol / Q000494:pharmacology / Q000627:therapeutic use*; D005260:Female; D006470:Hemorrhage / Q000150:complications / Q000453:epidemiology* / Q000209:etiology; D006728:Hormones / Q000494:pharmacology / Q000627:therapeutic use; D006734:Horse Diseases / Q000453:epidemiology / Q000209:etiology; D006736:Horses; D015994:Incidence; D008186:Luteolytic Agents / Q000494:pharmacology / Q000627:therapeutic use; D010049:Ovarian Diseases / Q000150:complications / Q000453:epidemiology* / Q000209:etiology; D006080:Ovarian Follicle / Q000473:pathology; D012102:Reproductive Control Agents / Q000494:pharmacology / Q000627:therapeutic use; D012189:Retrospective Studies; D012621:Seasons
D006063:Chorionic Gonadotropin; D006728:Hormones; D008186:Luteolytic Agents; D012102:Reproductive Control Agents; D003008:Cloprostenol