title: Mare and foal survival and subsequent fertility of mares treated for uterine torsion.
abstract: BACKGROUND
  Previous surveys have reported that mare and foal survival after correction of uterine torsion (UT) varies from 60 to 84% and from 30 to 54%, respectively. Furthermore, resolution via a standing flank laparotomy (SFL) has been associated with better foal, but not mare, survival.
  
  
  OBJECTIVE
  To compare the success of SFL with other correction methods (e.g. midline or flank laparotomy under general anaesthesia; correction per vaginam).
  
  
  METHODS
  Retrospective analysis of clinical records.
  
  
  METHODS
  Data on correction technique, stage of gestation, degree of rotation, survival and subsequent fertility for 189 mares treated for UT at 3 equine referral hospitals in The Netherlands during 1987-2007 were analysed.
  
  
  RESULTS
  Mean stage of gestation at diagnosis was 283 days (range 153-369 days), with the majority of UTs (77.5%) occurring before Day 320 of gestation. After correction of UT, 90.5% of mares and 82.3% of foals survived to hospital discharge, between 3 and 39 days later, and to foaling. Multivariable logistic regression indicated that correction method and stage of gestation at UT affected survival of foals and mares. For foals, survival was 88.7% after SFL compared with 35.0% after other methods (P = 0.001). When UT occurred at <320 days, 90.6% of foals survived, compared with 56.1% at ≥320 days (P = 0.007). For mare survival, an interaction between stage of gestation and correction method was detected (P = 0.02), with higher survival after SFL (97.1%) than other methods (50.0%) at <320 days of gestation (P<0.01). When UT occurred at ≥320 days, mare survival did not differ between techniques (76.0 vs. 68.8%; P = 0.6). Of 123 mares that were bred again, 93.5% became pregnant; fertility did not differ between mares treated by SFL (93.9%) and other techniques (87.5%; P = 0.9).
  
  
  CONCLUSIONS
  Standing flank laparotomy is the surgical technique of choice for resolving uncomplicated equine UT (i.e. with no coexisting gastrointestinal lesions) except when the stage of gestation exceeds 320 days.
authors: Lingehoeve Diergeneeskunde, Lienden, The Netherlands.
authors: T J P
authors: TJ
authors: Spoormakers
authors: Quantitative Veterinary Epidemiology Group, Wageningen Institute of Animal Sciences (WIAS), Wageningen University, Wageningen, The Netherlands.
authors: E A M
authors: EA
authors: Graat
authors: Equine Referral Centre Emmeloord, Emmeloord, The Netherlands.
authors: F
authors: F
authors: ter Braake
authors: Department of Equine Health, Utrecht University, Utrecht, The Netherlands.|Department of Animal Reproduction, University of Pretoria, Pretoria, South Africa.
authors: T A E
authors: TA
authors: Stout
authors: Quantitative Veterinary Epidemiology Group, Wageningen Institute of Animal Sciences (WIAS), Wageningen University, Wageningen, The Netherlands.
authors: H J
authors: HJ
authors: Bergman
mesh_terms: D000818:Animals; D005260:Female; D006734:Horse Diseases / Q000401:mortality / Q000628:therapy*; D006736:Horses; D015999:Multivariate Analysis; D016017:Odds Ratio; D011247:Pregnancy; D011248:Pregnancy Complications / Q000401:mortality / Q000473:pathology / Q000662:veterinary*; D011256:Pregnancy Outcome / Q000662:veterinary*; D012189:Retrospective Studies; D016019:Survival Analysis; D014102:Torsion Abnormality / Q000150:complications / Q000628:therapy / Q000662:veterinary*; D014591:Uterine Diseases / Q000628:therapy / Q000662:veterinary*
keywords: colic; flank laparotomy; horse; standing; uterine torsion