International Journal of Morphology
versión On-line ISSN 0717-9502
FELIPE, Antonio Eduardo; MASSON, Patricia Gabriela; RODRIGUEZ, Julio Armando y ALZOLA, Ricardo Horacio. External Morphological Characterization of 60-Days Gestation Myocastor coypus (Coypu) Fetuses. Int. J. Morphol. [online]. 2006, vol.24, n.1, pp. 71-76. ISSN 0717-9502. http://dx.doi.org/10.4067/S0717-95022006000100014.
The main objective of this work was to carry out the external morphology characterization of 60-days gestation Myocastor coypus (coypu) fetuses since this stage could be considered a crucial point in the prenatal development in this species. Fourteen fetuses out of three litter were analised. Gestational sacs weighing 3.81 ± 0.27 g showed an elliptical shape with the larger axis along the direction of the uterus. The average weight of fetuses was 1.13 ± 0.19 g, the head-to-tail lenght was 1.99 ± 0.87 cm, the cephalic lenght was 1.01 ± 0.37 cm, and the biparietal diameter was 0.63 ± 0.06 cm. Specimens showed differentiation in corporeal, limbs and tail regions; also showed interdigital membranes, well defined optical vesicles and lateral ear lobe sprouts. Comparative analysis of coypu fetuses and equivalent stages of other mammal species will allow to establish similitudes and differences that would permit to mark particularities in the ontogeny of Myocastor coypus
Palabras clave : Fetal morphology; Coypu; Myocastor coypus.