RESUMO
Knowledge of wild species embryonic development is important for their maintenance in captivity or the wild. The objective of the present study was to characterize the external morphology and define the biometry of greater rhea embryos and fetuses at different stages of development. A total of 41 embryos and fetuses were analyzed to describe their external morphology using a stereoscopic microscope. The crown-rump (CR), total length (TL), cephalocaudal length (CCL), biparietal diameter (BPD), beak, humerus and tibio-tarsal lengths were measured by digital pachymeter, millimetric scale ruler and cotton thread. The weight of the embryos and fetuses was measured on digital scales. The greater rhea embryos at 5, 6 and 7 days incubation presented a "C" shape. At 9, 10 and 11 days the eyes were big and pigmented. At 11, 12 and 13 days the eyelid covered more than half the eye, resulting in an oval slit. In 14 and 15 day-old embryos, the skin was still thin and the ribs evident, but at 18 days this structure was thicker. In embryos at 21 and 27 days of development closed eyelids were observed forming an eyelid slit, and the eye ball was less pronounced at 27 days. Weight gain presented an exponential growth curve, while measurements such as TL, DBP, beak, humerus and tibio-tarsal length had linear growth over time. Thus it was possible to characterize the greater rhea embryos and fetuses at several incubation ages using their external morphology and morphometric analyses.
Assuntos
Reiformes/embriologia , Animais , Biometria , Embrião não Mamífero/anatomia & histologia , Desenvolvimento EmbrionárioRESUMO
Stem cells are present in the adult tissues of most diverse species. Bone marrow is recognized to be the most exploited site to obtain stem cells and cell progenitors. The objective of the present study was to characterize hematopoietic progenitor (HP) morphology and analyze the performance of adherent cell progenitors (ACPs) cultivated in vitro from black-rumped agouti bone marrow (Dasyprocta prymnolopha). Bone marrow aspirates were obtained from tibia crest and used to prepare histological slides and identify cell morphology. Cells were also scattered on culture plates for later isolation, expansion, and quantification. Smears obtained from bone marrow demonstrated HPs at different stages of maturity. In culture, these cells showed fibroblastoid morphology and a strong tendency to form colonies, demonstrated by the presence of cell aggregates, cytoplasmic elongations lying side by side. An 80% cell confluence was observed at 18 days in culture and progressive reduction in the percentage of nonadherent mononuclear cells. After eight passes, a mean cell viability of 96.07% was observed, from a pool of 1.6 × 10(7) cells (ACP). Thirteen 25-cm(2) culture bottles were trypsinized, resuspended in freezing medium, stored in 14 criotubes at a concentration of 1 × 10(6) cells per milliliter, and placed in liquid nitrogen at -196°C. Agouti bone marrow demonstrated high plasticity, moreover different HP lines, and a population of adherent cells demonstrated morphology similar to mesenchymal stem cells in culture.