Fetal morphological features and abnormalities associated with equine early pregnancy loss.
developmental abnormalities
equine reproduction
fetus
horse
pregnancy outcome
Journal
Equine veterinary journal
ISSN: 2042-3306
Titre abrégé: Equine Vet J
Pays: United States
ID NLM: 0173320
Informations de publication
Date de publication:
May 2021
May 2021
Historique:
revised:
15
07
2020
received:
04
12
2019
accepted:
15
08
2020
pubmed:
2
9
2020
medline:
13
4
2021
entrez:
2
9
2020
Statut:
ppublish
Résumé
Early pregnancy loss (EPL) occurs in approximately 8% of equine pregnancies, although the aetiology is mostly unknown and embryonic/fetal morphological abnormalities associated with EPL are not defined. To compare the morphology of EPL to clinically normal embryos/fetuses and previously described embryonic/fetal developmental milestones. To identify morphological abnormalities associated with equine EPL. Observational case-control study. Embryos/fetuses were obtained from clinically normal Thoroughbred and pony pregnancies (n = 11) and following EPL from Thoroughbred mares (n = 27). The crown-rump length (CRL) of embryos/fetuses was measured and macroscopic morphology and developmental age were determined independently by three blinded examiners. Sagittal sections of EPL (n = 13) and control (n = 6) embryos/fetuses were assessed microscopically. Fisher's exact test was used to determine significance (P < .05) and correlations were expressed by Pearson coefficient. Age and CRL were strongly positively correlated in clinically normal Thoroughbred and reference (n = 15, R = .9 (95% CI: 0.8-1.0), R Autolysis significantly affected 15/27 EPL embryos/fetuses, excluding them from complete assessment. The IUGR reference cut-off values were based on a small number of controls. Morphological features associated with equine EPL were a mismatch between embryonic/fetal size and age, and alterations of the developing neural tissue and localised subcutaneous haemorrhage. Failed neural tube closure was confirmed as a rare specific abnormality.
Sections du résumé
BACKGROUND
BACKGROUND
Early pregnancy loss (EPL) occurs in approximately 8% of equine pregnancies, although the aetiology is mostly unknown and embryonic/fetal morphological abnormalities associated with EPL are not defined.
OBJECTIVES
OBJECTIVE
To compare the morphology of EPL to clinically normal embryos/fetuses and previously described embryonic/fetal developmental milestones. To identify morphological abnormalities associated with equine EPL.
STUDY DESIGN
METHODS
Observational case-control study.
METHODS
METHODS
Embryos/fetuses were obtained from clinically normal Thoroughbred and pony pregnancies (n = 11) and following EPL from Thoroughbred mares (n = 27). The crown-rump length (CRL) of embryos/fetuses was measured and macroscopic morphology and developmental age were determined independently by three blinded examiners. Sagittal sections of EPL (n = 13) and control (n = 6) embryos/fetuses were assessed microscopically. Fisher's exact test was used to determine significance (P < .05) and correlations were expressed by Pearson coefficient.
RESULTS
RESULTS
Age and CRL were strongly positively correlated in clinically normal Thoroughbred and reference (n = 15, R = .9 (95% CI: 0.8-1.0), R
MAIN LIMITATIONS
CONCLUSIONS
Autolysis significantly affected 15/27 EPL embryos/fetuses, excluding them from complete assessment. The IUGR reference cut-off values were based on a small number of controls.
CONCLUSIONS
CONCLUSIONS
Morphological features associated with equine EPL were a mismatch between embryonic/fetal size and age, and alterations of the developing neural tissue and localised subcutaneous haemorrhage. Failed neural tube closure was confirmed as a rare specific abnormality.
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
530-541Subventions
Organisme : Thoroughbred Breeders Association
ID : VET/RS/250
Organisme : Thoroughbred Breeders Association
ID : TBA/EPL/2018
Organisme : Horserace Betting Levy Board
Informations de copyright
© 2020 The Authors. Equine Veterinary Journal published by John Wiley & Sons Ltd on behalf of EVJ Ltd.
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