Ultrasonographic measurement of the equine fetal vitreous body length for predicting days to parturition in Pura Raza Española horses

Authors

  • Patricio Razquin-Echeverriarza Universidad Nacional, Escuela de Medicina Veterinaria, Costa Rica
  • Patrick M. McCue Colorado State University, Department of Clinical Sciences, United States
  • Paula Cappella-Flores Private practitioner, Costa Rica
  • Bernardo Vargas-Leitón Universidad Nacional, Escuela de Medicina Veterinaria, Costa Rica
  • Sandra Estrada-König Universidad Nacional, Escuela de Medicina Veterinaria, Costa Rica

DOI:

https://doi.org/10.15359/rcv.37-2.1

Keywords:

Pura Raza Española, Mares, Ocular, Diameter, Parturition, Ultrasonography

Abstract

Ultrasonographic measurement of the fetal vitreous body length to predict parturition date in horses has shown substantial differences between breeds. PRE (Pura Raza Española or Purebred Spanish Horse) is an important breed in the equine industry of Costa Rica. No data for prediction of parturition exists for PRE using fetal ocular measurements. Between-observer agreement has never been evaluated for fetal ocular measurements on horses. A total of 86 ocular diameters were measured by a veterinarian in twelve PRE mares from day 240 of gestation until parturition. Forty measurements were repeated by a senior veterinary student to determine between-observer agreement. Transrectal ultrasonography was performed in each occasion, and a mean was calculated of the three measurements obtained. Two nonlinear regression equations were derived using days before parturition and age of gestation as dependent variables and vitreous body length as the independent variable. The model obtained for days before parturition was y = 1123.8 -55.5*x+0.689*x2, where “y” represents days before parturition and “x” represents fetal ocular diameter (r2= 0.79; P<0.001); and y = -710.6+51.8*x -0.644*x2, where “y” represents age of gestation and “x” represents ocular diameter (r2= 0.75; P<0.001). Pearson correlation coefficient and paired t-test were performed to assess the between-observer agreement. No significant differences (p=0.86) were detected between-observers, indicating high reproducibility. This study concluded that ocular diameter measurement can be reproduced with high precision by different veterinarians, and either model using days before parturition or age of gestation can be used to predict parturition in PRE mares when breeding dates are unknown.

References

Allen, W.R., Wilsher S., Stewart, F., Ousey, J. & Fowden, A. 2002. The influence of maternal size on placental, fetal and postnatal growth in the horse. II. Endocrinology of pregnancy. J Endocrinol; 172:237–46. doi:10.1677/joe.0.1720237

Bucca, S., Fogarty, U., Collins, A. & Small, V. 2005. Assessment of feto-placental well-being in the mare from mid-gestation to term: Transrectal and transabdominal ultrasonographic features. Theriogenology; 64:542–57. doi: 10.1016/j.theriogenology.2005.05.011

Hartwig, F.P., Antunez, L., Dos Santos, R.S., Lisboa, F.P., Pfeifer, L.F.M. & Nogueira, CEW. 2012. Determining the gestational age of crioulo mares based on a fetal ocular measure. J Equine Vet Sci; 33:557–60. doi: 10.1016/j.jevs.2012.08.203

Hendriks, W.K., Colenbrander, B., Van der Weijden, G.C. & Stout, T.A.E. 2009. Maternal age and parity influence ultrasonographic measurements of fetal growth in Dutch Warmblood mares. Anim Reprod Sci; 115:110–23. doi: 10.1016/j.anireprosci.2008.12.014

Henneke, D.R., Potter, G.D., Kreider, J.L. & Yeates, B.F. 1983. Relationship between condition score, physical measurements and body fat percentage in mares. Equine Vet J; 15:371–2. doi: https://doi.org/10.1111/j.2042-3306.1983.tb01826.x

Kahn, V.W. & Leidl, W. 1987. Die ultraschall-biometrie von pferdefeten in utero und die sonographische darstellung ihrer organe. Dtsch Tierarztl Wschr; 94:497–540

Lanci, A., Castagnetti, C., Ranciati, S., Sergio, C. & Mariella, J. 2018. A regression model including fetal orbit measurement to predict parturition in Standardbred mares with normal pregnancy. Theriogenology; 126:153–158. https://doi.org/10.1016/j.theriogenology.2018.12.020

Murase, H., Endo, Y., Tsuchiya, T., Kotoyori, Y., Shikichi, M. & Ito, K. 2014. Ultrasonographic Evaluation of Equine Fetal Growth Throughout Gestation in Normal Mares Using a Convex Transducer. J Vet Med Sci; 76:947–53. doi:10.1292/jvms.13-0259

Renaudin, C.D., Gillis, C.L., Tarantal, A.F. & Coleman, D.A. 2000. Evaluation of equine fetal growth from day 100 of gestation to parturition by ultrasonography. J Reprod Fertil; 56:651–60.

Rollins, C.E. & C. H.W. 1951. Environmental Sources of Variation in the Gestation Length of the Horse. J Anim Sci; 10:789–796. doi:https://doi.org/10.2527/jas1951.104789x

Turner, R.M., McDonnell, S.M., Feit, E.M., Grogan, E.H. & Foglia, R. 2006. Real-time ultrasound measure of the fetal eye (vitreous body) for prediction of parturition date in small ponies. Theriogenology; 66. doi: 10.1016/j.theriogenology.2005.11.019

Watson, P.F. & Petrie, A. 2010. Method agreement analysis: A review of correct methodology. Theriogenology; 73:1167–79. doi: 10.1016/j.theriogenology.2010.01.003

Published

2019-10-03

How to Cite

Ultrasonographic measurement of the equine fetal vitreous body length for predicting days to parturition in Pura Raza Española horses. (2019). Ciencias Veterinarias, 37(2), 1-10. https://doi.org/10.15359/rcv.37-2.1

How to Cite

Ultrasonographic measurement of the equine fetal vitreous body length for predicting days to parturition in Pura Raza Española horses. (2019). Ciencias Veterinarias, 37(2), 1-10. https://doi.org/10.15359/rcv.37-2.1

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