Obstetrician's view of the physiology of equine parturition and dystocia.

The author reviews 40 years of clinical experience including more than 1000 cases of dystocia in mares of different breeds. The high incidence of stillbirth and perinatal mortality of the foal, severe lesions of the genital tract developing during foaling and in the early post partum period are discussed and suggestions made for their prevention and treatment. The advantages of partial embryotomy to avoid unnecessary caesarean sections are emphasised. Special attention is given to the causes of and approach to cases of prolonged gestation; to dystocia caused by retroversion of preparturient torsion of the uterus; and to transverse presentation developed from bicornual pregnancy, regarded as the most important indication for caesarean section. Recommendations are proposed to improve the results of caesarean section for the mare and foal.