Avaliação morfológica das membranas fetais e da placenta de Mazama gouazoubira (veado-catingueiro) de vida livre no terço inicial da gestação

Abstract

Pesq. Vet. Bras. 31 (7) Mazama gouazoubira is a small-sized deer, which can be found in South America, from southern Uruguay to the north of Mato Grosso, Brazil. This study aimed to describe the fetal membranes and placenta of M. gouazoubira in the first third of pregnancy. Samples collected were macroscopically and microscopically analyzed. Uterus examination demonstrated univitelinic gestation with an embryo measuring a crown-rump length of 13mm. In the embryo analysis we could identify the pigmented eye, auricular hillocks, mesonephron and early metanephron, liver and its external prominence, stomach, thoracic members and buds of pelvic members. Placenta was oligocotyledonary and nine caruncles were found in the uterus. Gestational sac measured 15cm in length, and, as observed in the early gestation of domestic ruminants, cotyledons could not be identified macroscopically. A weak adhesion was found between caruncles and chorioallantoic membrane (cotyledons) forming the placentomes. The chorioallantoic membrane showed a well-vascularized allantoid composed by a thin layer of cells with stretched nucleus and cytoplasm. On the other side of the membrane, the chorion was composed by cubic cells with scant cytoplasm and large-rounded nuclei, features of trophoblast cells. Involving the embryo we identified a two-layered amniotic sac. Layers could be mechanically separated and had similar morphology, showing a non-vascularized squamous epithelium. There was no yolk sac in the gestational stage of this specimen. We concluded that the placenta of M. gouazoubira is an oligocotyledonary placenta, as observed in others cervids, and that the fetal membranes showed similarities with those from other domestic ruminants, including cytological characteristics. Further studies are required in order to determine the presence of the yolk sac and its regression time.INDEX TERMS: Yolk sac, chorioallantoic membrane, embryo, oligocotyledonary placenta, placentome.

Estudo histológico e comparativo das papilas linguais dos cervídeos Mazama americana e Mazama gouzoubira por microscopia de luz e eletrônica de varredura

“…Algumas espécies do gênero Mazama são frugívoras, e seu habitat se estende do sul do Uruguai ao norte do estado do Mato Grosso e da Cordilheira dos Andes até o Atlântico para a Mazama gouazoubira, enquanto a Mazama americana do México ao norte da Argentina (Duarte 2006, Abril et al 2010, Ferreira et al 2011.…”

La evaluación morfológica del hígado de un ejemplar de venado Mazama gouazoubira (Fischer, 1814)

“…O fígado em mamíferos domésticos representa a maior glândula do corpo e desempenha funções essenciais à vida, atua no metabolismo de carboidratos, proteínas e gorduras, possui ação desintoxicante, contribui para o armazenamento de glicose sob a forma de glicogênio e elimina diversas substâncias, fatores que conferem a este órgão uma grande importância (Dyce et al, 2004, PUBVET v.12, n.5, a90, p.1-4, Mai., 2018 Cunningham, 2011). Este fato leva muitos pesquisadores a estudar os múltiplos aspectos morfológicos desta glândula nas diferentes espécies, permitindo estabelecer uma anatomia comparativa (Ferreira et al, 2011, Schwarz, 2012.…”

Osteología del Miembro Torácico de la Corzuela Parda Mazama gouazoubira (G. Fischer, 1814) (Cetartiodactyla: Cervidae)

“…Tiene una masa corporal entre 17 y 23 kg, pequeños cuernos no ramificados, pelaje marrón con el tronco grisáceo y la parte ventral de la cola blanca. Se encuentra ampliamente distribuido desde el sur de Uruguay hasta el norte de Mato Grosso en Brasil y ocupa áreas forestales como campos, sabanas y catingas (Tiepolo & Tomas, 2006;Ferreira et al, 2011). Su población no se considera en peligro de extinción (Black-Decima & Vogliotti, 2016), excepto en Rio Grande do Sul y Rio de Janeiro, por la caza ilegal, la agricultura y la urbanización de su hábitat (Tiepolo & Tomas;Teixeira et al, 2010).…”