Pre-implantational timetable of embryonal development of Myocastor coypus (Coypu)

Abstract

-The purpose of the present study was to determine the chronology of the pre-implantation embryonic development in Myocastor coypus (coypu). It was carried out by daily colpocytological examination and controlled mating of 33 females. Oocytes and embryos were obtained by flushing from day 0 to day 10 post-coitus (p.c.). On day 1 p.c., oocytes predominated whereas on day 2 p.c. zygotes were predominant. The cleavage period was from day 3 to day 6 p.c.. Morulae were collected from day 6 to day 9 p.c., whereas blastocysts were collected on days 8 and 9. From oviduct flushing, the embryos in the zygote stage and up to the morula stage with less than a 30-cell stage were recovered. Embryos in the morula stage with 30 or more cells and up to the growing blastocyst stage were collected from the flushing of hemiuteri. embryo / Myocastor coypus / preimplantational development / timetableRésumé -Chronologie du développement embryonnaire pré-implantatoire de Myocastor coypus (Coypou). Le but de ce travail est d'établir la chronologie du développement embryonnaire pré-implantatoire de Myocastor coypus (coypou). Après un suivi des cycles oestriens par examen histologique des frottis vaginaux, 33 femelles ont été accouplées. Les ovocytes et les embryons sont examinés dans les lavages du tractus génital entre les jours 0-10 post-coïtum (p.c.). Au jour 1 p.c., les ovocytes sont majoritaires tandis qu'au jour 2 les zygotes prédominent. La période de segmentation est comprise entre les jours 3-6 p.c. Les morulas sont collectées du jour 6 au jour 9 p.c. et les blastocystes sont observés aux jours 8-9 p.c. Dans les lavages tubaires, les embryons collectés sont entre les stades zygotique et morula inférieure à 30 cellules. Les embryons récoltés dans les lavages uté-rins sont au stade morula (30 cellules ou plus) et au stade blastocyste. embryon / Myocastor coypus / développement pré-implantatoire / table chronologique Reprod. Nutr. Dev. 42 (2002) 15-24 15

Comparative analysis of the morphology and histochemistry of the duodenum of the coypu (Myocastor coypus bonariensis) during its prenatal and postnatal development

“…Up to the present time, few studies are available on the developmental biology of M. coypus bonariensis (Felipe et al, 1999(Felipe et al, , 2002Felipe and Masson, 2008). Among such researches, those related to the ontogenetic development of the digestive system represent an important landmark because of their possible transference to experimental essays on diet.…”

Fetal growth and development of the coypu (Myocastor coypus): Prenatal growth, tooth eruption, and cranial ossification

“…Although the development (i.e., size and morphological changes) of the coypu from early embryonic growth is well described (Chapman et al 1980;Felipe et al 2002Felipe et al , 2004, little is known concerning morphogenesis during the fetal stage. Newson (1966) obtained 19 l of various known ages and correlated fetal weight with stage of gestation.…”

Observations on the Fetal Morphology in Myocastor Coypus Bonariensis (Coypu) (Rodentia, Myocastoridae)

“…Till date, the systematized information on the developmental biology of the coypu is scarce (Felipe et al., 1999, 2002), with some general references available on other hystricognath rodents (Roberts and Perry, 1974). This determines the need to perform studies contributing to enhance the knowledge on the embryology of this species.…”