title: Prenatal development of the agouti (Dasyprocta prymnolopha Wagler, 1831): External features and growth curves.
abstract: The gestation period in agoutis can range from 104 to 120 days. Knowledge regarding the morphological characteristics of embryos and fetuses is important as a base for studies in reproduction biotechnology, such as in vitro fertilization, embryo transfer and helps in determining congenital anomalies during the development phase. Thus, given the importance and lack of information about agouti embryology, the objective of this study was to characterize the external morphology and define the biometry of embryos and fetuses, at different days of development. Nine females were submitted to daily colpocytology to identify the estrus, confirm mating and identify day zero of the gestation. When the mating was confirmed they were weighed, underwent abdominal ultrasonography and surgery was conducted on the females at the gestational ages of 25, 30, 35, 40, 45, 50, 75 and 100 days. Sixteen embryos/fetuses were weighed and measured. Agouti embryos at 25 days after mating are "C" shaped, with primitive structures, 0.4±0.01cm crown-rump and weighed 0.06±0.01g; at 30 days after mating the crown-rump was 0.95±0.07cm and weighed 0.28±0.00g; at 35 days after mating the crown-rump was 155±0.07cm and weighed 0.38±0.01g; at 40 days after mating the crown-rump was 2.25±0.21cm and weighed 1.25±0.07g; at 45 days after mating the crown-rump was 3.45±0.35cm and weighed 2.75±0.64g; at 50 days after mating the crown-rump was 5.0±0.3cm and weighed 7.01±2.6g; at 75 days after mating, the skin was dark, the crown-rump was 10.0±0.14cm and weighed 55.2±0.07g. At 100 days after mating, the crown-rump was 13.8±0.49cm and fetuses weighed 136.7±9.40g. Based on the morphological data assessed the embryo and fetus age could be assessed and the size and average weight of agouti embryos was established.
authors.affiliation: Animal Science Postgraduate Program, Federal University of Piauí, Teresina, PI, Brazil.
authors.forename: Eunice Anita de Moura
authors.initials: EA
authors.lastname: Fortes
authors.forename: Maíra Soares
authors.initials: MS
authors.lastname: Ferraz
authors.forename: Dayseanny Oliveira
authors.initials: DO
authors.lastname: Bezerra
authors.forename: Aírton Mendes Conde
authors.initials: AM
authors.lastname: Júnior
authors.forename: Rosa Maria
authors.initials: RM
authors.lastname: Cabral
authors.forename: Francisco das Chagas Araújo
authors.initials: Fd
authors.lastname: Sousa
authors.forename: Hatawa Melo
authors.initials: HM
authors.lastname: Almeida
authors.forename: Gerson Tavares
authors.initials: GT
authors.lastname: Pessoa
authors.forename: Danilo José Ayres de
authors.initials: DJ
authors.lastname: Menezes
authors.forename: Sérgio Paulo Lima
authors.initials: SP
authors.lastname: Guerra
authors.forename: Ivan Barbosa Machado
authors.initials: IB
authors.lastname: Sampaio
authors.forename: Antônio Chaves
authors.initials: AC
authors.lastname: Assis Neto
authors.forename: Maria Acelina Martins de
authors.initials: MA
authors.lastname: Carvalho
mesh_terms: D000818:Animals; D018568:Crown-Rump Length; D005260:Female; D047109:Fetal Development / Q000502:physiology*; D005333:Fetus / Q000502:physiology*; D011247:Pregnancy; D012377:Rodentia / Q000196:embryology*; D016216:Ultrasonography, Prenatal / Q000662:veterinary
keywords: Agoutis; Embryo; Fetus; Growth; Morphology