Dystocia in the horse is a life-threatening emergency. Prompt and effective intervention is essential to improve the outcome for both mare and foal. Resolution is possible via assisted vaginal delivery, controlled vaginal delivery, fetotomy or Caesarean section. Guidelines exist but the final choice is influenced by several factors including fetal viability, duration of dystocia, availability of obstetric assistance and financial considerations. The purpose of this study was to report our experience in the management of dystocia in Miniature horses and Shetland ponies. Data were collected from the records of 17 mares treated between 2020 and 2022. According to the clinic's protocol, correction was first attempted by assisted vaginal delivery; in case of failure, fetotomy or Caesarean section was performed. All mares were referred to the clinic after prolonged labor and only 2 (12%) were presented with their foal still alive. In 8/17 mares, the foal was delivered via assisted vaginal delivery. In 6/17 mares, a partial fetotomy was performed. In the 3 remaining cases, a conventional Caesarean section was proposed but not considered due to its financial cost; a field Caesarean section was therefore performed. General anesthesia was maintained using a continuous rate infusion of triple drip consisting of a combination of 250 ml sodium chloride (0.9%), 250 ml guaifenesin (10%), 20 ml ketamine (10%) and 1 ml detomidine (1%).After local anesthesia, a low left flank celiotomy in lateral recumbency was performed. Overall survival rate of the presented mares was 59% (10/17). Mares’ survival rates following assisted vaginal delivery, fetotomy and field Caesarean section were respectively 63% (5/8), 33% (2/6) and 100% (3/3). Both foals alive at arrival survived delivery and one (6%) survived to discharge. While in warmblood horses, fetotomy has been proven rapid and safe (Norton et al. Equine Vet J 2007;39:37-41), in small breeds the feasibility of fetotomy is largely hampered by their body size and is deemed too stressful for the exhausted mares. In addition, complications after dystocia are aggravated in small breeds due to the high risk of hypertriglyceridemia and consequently hyperlipemia. Hypertriglyceridemia was determined in 35% (6/17) of the mares and hyperlipemia was the cause of death in 3 out of these 6 mares. Caesarean section is associated with several complications, such as retained placenta, metritis, laminitis and uterine hemorrhage. Due to a lack of asepsis in a non-optimal setting, peritoneal or incisional infections could be a weak point of the field Caesarean section. Our results, supported by those of others (Gandini et al. Reprod Dom Anim 2013;48:49-51), are promising for considering field Caesarean section as a preferable resolution to dystocia in Miniature horses and Shetland ponies.
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