title: Intrafollicular treatment with prostaglandins PGE2 and PGF2α inhibits the formation of luteinised unruptured follicles and restores normal ovulation in mares treated with flunixin-meglumine.
abstract: BACKGROUND
  Haemorrhagic anovulatory follicle is the most common pathological anovulatory condition in the mare, but its cause remains unknown. An experimental model to induce luteinised unruptured follicles (LUF) with flunixin-meglumine (FM) has been developed. Luteinised unruptured follicles share similar morphological and hormonal characteristics with haemorrhagic anovulatory follicles.
  
  
  OBJECTIVE
  To test the effect of intrafollicular administration of prostaglandins PGE2 and PGF2α during the periovulatory period on ovulation and pregnancy in FM-treated mares.
  
  
  METHODS
  In vivo experiment in a crossover design.
  
  
  METHODS
  Five mares were followed during 2 oestrous cycles each. All mares were given FM at 1.7 mg/kg bwt i.v. every 12 h from Hour 0 (Hour 0 = human chorionic gonadotrophin treatment) to Hour 36. In treatment cycles (n = 5), at Hour 32 the preovulatory follicle was punctured and 0.5 ml of a solution containing 500 μg of PGE2 and 125 μg of PGF2α was deposited within the follicle. In control cycles, water for injection was administered into the follicle at the same time. In 3 control and 3 treatment cycles, mares were also inseminated at Hour 24. Diagnosis of ovulation/LUF formation and pregnancy was performed by ultrasound examination between Hours 36 and 72 and 14 days after ovulation/LUF formation, respectively.
  
  
  RESULTS
  During the treatment cycles, all mares ovulated normally (100% ovulation rate) 36-48 h after human chorionic gonadotrophin, while in 4 of 5 control cycles the mares developed an LUF (80%, P<0.05). All 3 inseminated mares became pregnant in the treatment cycles, but not in the control cycles.
  
  
  CONCLUSIONS
  Intrafollicular treatment with PGE2 and PGF2α overcame the anovulatory effect of FM. This sheds new insights into the knowledge on the possible therapeutic options for ovulatory failure in the mare.
authors.affiliation: Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad CEU, Cardenal Herrera, Alfara del Patriarca, Spain.
authors.forename: R
authors.initials: R
authors.lastname: Martínez-Boví
authors.affiliation: Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad CEU, Cardenal Herrera, Alfara del Patriarca, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Cuervo-Arango
mesh_terms: D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000494:pharmacology; D003002:Clonixin / Q000031:analogs & derivatives* / Q000494:pharmacology; D015237:Dinoprost / Q000494:pharmacology*; D015232:Dinoprostone / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006736:Horses; D034461:Luteinization / Q000187:drug effects*; D006080:Ovarian Follicle / Q000187:drug effects*; D010060:Ovulation / Q000187:drug effects*; D011247:Pregnancy
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; C014558:flunixin meglumine; D015237:Dinoprost; D015232:Dinoprostone; D003002:Clonixin
keywords: horse; luteinised unruptured follicle; mare; ovulation; prostaglandin