PREVALENCE OF FETAL MALDISPOSITIONS IN EQUINE REFERRAL HOSPITAL DYSTOCIAS

A retrospective investigation was performed to determine the populatio n characteristics of horses presented for dystocia at 2 equine referra l hospitals and the types of fetal maldispositions among these horses, The study population consisted of a similar number of Thoroughbreds ( 25%), Standardbreds (24%) and draft horses (22%). Most of the current literature pertaining to equine obstetrics is based on a predominately draft horse population (63%). The latter population appeared to have more transverse presentations (P = 0.06), possibly because of the high er number of draft mares, In our study, 43% (6/14) of the transverse p resentations occurred in draft breeds, Furthermore, 18% of the draft m are dystocias (6/33) were transverse presentations whereas only 8% (6/ 73) of the 2 major light breeds (Thoroughbred n = 3; Standardbred n = 3) had transverse presentation dystocias, Despite the significant bree d differences between the 2 populations (P < 0.001), the prevalence of all other fetal maldispositions was not different from those previous ly reported, Severe dystocia was often multifactorial, with 86% of cas es involving malposture and over half (58%) of these involving more th an one extremity, Head and/or neck deviation were a major reason for r eferral, In 30% of cases malposition was a factor, and abnormal presen tation was involved in 24% of referrals.