ABSTRACT
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.
Subject(s)
Rheiformes/embryology , Animals , Biometry , Embryo, Nonmammalian/anatomy & histology , Embryonic DevelopmentABSTRACT
Thirty adult agoutis (Dasyprocta primnolopha) from the Nucleus of Study and Preservation of Wild Animals at the Federal University of Piauí were used. Blood scrubs of these animals were colored by the Leishman method and analyzed in light microscopy. The cells had been measured using programs that analyze images (Leica QWin - Image Processing and Analysis Software). Mature erythrocytes, basophil reticulocytes, lymphocytes, eosinophils, neutrophils, monocytes, and thrombocytes were identified. Agoutis' erythrocytes presented elliptical form, without nucleus with an average diameter of 5.64 micromeres ± 0.38. The lymphocytes are spherical cells with scarce cytoplasm, dense and with a very centralized rounded nucleus measuring an average diameter of 13.20 micromeres ± 0.35. The monocytes are slightly basophilic, with a spherical nucleus, central constriction, and an average diameter of 20.59 micromeres ± 0.32. The neutrophils are spherical, with a polymorphic lobulated nucleus, with an average diameter of 11.2 micromeres ± 0.20. The eosinophils are spherical with lobulated nucleus and with an average diameter of 14.25 micromeres ± 0.36. Only five basophils were observed, with abundance of cytoplasmic granules with 9.8 micrometers of diameter ± 0.30. Thrombocytopenic pleomorphism was frequent. There were similarities in the cellular constituents in peripheral blood of agoutis and of other rodents and humans. The cellular types from the peripheral blood, the morphology, and morphometry of the blood's cells did not vary according to sex.