Parturition, dystocia and foal survival: A retrospective study of 1047 births

Abstract

SummaryReason for performing study: An understanding of the normal events of foaling, causes of dystocia and clinical outcomes is important for equine practitioners. Objectives: The goals of the present study were to: 1) evaluate factors that influence gestation length; 2) report duration of Stage II labour; 3) determine the frequency of dystocia and premature placental separation; and 4) determine the relationship between problems at foaling and foal survival. Materials and methods: Foaling records of 1047 mare births were evaluated. Results: The average gestation length was 341 Ϯ 0.3 days, with no effect of mare age or breed observed. Mares carrying male fetuses had a longer gestation (PՅ0.001) than mares carrying female fetuses. A majority (52.8%) of mares foaled at night between 2000 h and 0200 h when the facility was quiet. Dystocia occurred in 10.1% of all births and the incidence rate was higher in Thoroughbred mares than in Quarter Horse mares. The most common cause of dystocia was abnormalities of fetal posture. A delay in foal delivery beyond 40 min of Stage II of labour was associated with a significant increase in foal mortality. In addition, an increase in foal morbidity and mortality was noted when the interval from birth to standing or birth to nursing was prolonged. Conclusion: Early detection and rapid appropriate intervention are critical to foal survival in an equine dystocia. Potential relevance: Equine veterinarians should counsel horse owners that early recognition of a foaling problem and rapid, appropriate intervention are critical to the survival of a foal.

Factors affecting gestational length in the Mangalarga Paulista breed

“…These results differ from the majority of data for different breeds, in which the gestation length for colts was longer than that for fillies (Bos and Van Der Mey, 1980;Davies Morel et al, 2002;Pérez et al, 2003;Valera et al, 2006;Satué et al, 2011a b;Aoki et al, 2012;McCue and Ferris, 2012). Only few publications were not able to detect a significant influence of gender on the length of gestation (Campitelli et al, 1982;Valente et al, 2006), as it was found in our study.…”

“…Allen et al (2002), Davies Morel et al (2002 and Galvin and Corley (2010) obtained a mean of 338 ± 6.9, 344.1 ± 0.49 and 340.03 days of gestation for Thoroughbred mares, respectively, with a minimum of 312 and a maximum of 383 days. McCue and Ferris (2012) found a gestation mean of 341 ± 0.3 days in Thoroughbreds and QHs. Even when comparing the same breeds, a wide variation in gestation length is found, as can be observed in the aforementioned studies.…”

Time of foaling in Arabian mares raised in Tiaret, Algeria

“…It was reported that age of mares significantly influenced length of gestation. Although, a negative correlation between the age of mares and gestation length was reported, young mares have longer gestation than old mares [1] .…”

“…However the maximal incidence was observed between 10 pm and 11 pm. Also a majority (52.8%) of mares foaled at night between 8 pm and 2 am [1] . E-mail: nsvahedi@yahoo.com…”

“…Length of gestation in the mare is highly variable, and the variability in physical signs of imminent parturition makes predicting foaling particularly difficult [1] . Generally, gestation lengths were 320-360 d which was reported by Whittaker et al [2] .…”