Magnetic resonance microscopy atlas of equine embryonic development

Abstract

The equine atlas may serve as a foundation and scaffold for improved anatomical labelling, spatial and temporal data integration and further understanding of physiological and pathophysiological processes involved in development and disease.

Fetal morphological features and abnormalities associated with equine early pregnancy loss

“…Gestational and developmental age coincided for the majority of the ageable EPL embryos/fetuses in the present study, thus in alignment with the median maximum uterine retention time post-demise of 4 days. Gestational and developmental age did not align in 2/27 embryos/ fetuses obtained from mares suffering pregnancy failure.Despite the age-appropriate developmental morphology of embryos/fetuses being confirmed above, a correlation between gestational age and CRL, as described by others,17 was not observed among the EPL specimens, a finding that persisted following exclusion of conceptuses with prolonged uterine retention. This suggests a general mismatch of embryonic/fetal size and age.…”

“…A similar proportion of EPL embryos/fetuses were agreed by both examiners to be not ageable (11/27) during uterine lavage or processing, Table S4). Gestational age and CRL of EPL embryos/fetuses were compared with reference values published by Jenner et al 17 (Table S4). Two fetuses were markedly (CRL of 9 and 10.5 mm) and one was mildly undersized (16.4 mm).…”

“…Specific abnormalities have been reported in 16.4% human fetuses, 13 with the central nervous (CNS), cardiovascular (CVS) and urinary system presenting as the most commonly affected anatomical structures. 12,14 Limited macroscopic and histological descriptions exist for normal equine fetuses of different gestational ages, [15][16][17] although no data are available on the morphological features of fetuses obtained from mares suffering EPL. Further, whether developmental abnormalities, described in early human fetuses, are present in the horse is unknown.…”

“…Limited macroscopic and histological descriptions exist for normal equine fetuses of different gestational ages, 15‐17 although no data are available on the morphological features of fetuses obtained from mares suffering EPL. Further, whether developmental abnormalities, described in early human fetuses, are present in the horse is unknown.…”

The embryogenesis of the equine femorotibial joint: The equine interzone

“…Despite the high incidence of cartilage and joint disease in horses and the popularity of horses as research animals for osteoarthritis and cartilage tissue engineering, there are no studies of the equine interzone and the timing of interzone formation is not known. Using magnetic resonance microscopy in a companion study, we narrowed down the time frame during which interzone formation probably occurs to gestational Days 35–50 . In the current study, we performed high‐resolution episcopic microscopy (HREM) , histology and immunohistochemistry (IHC) to determine when the femorotibial interzone forms in the horse.…”