Carlos Alberto Palmeira Sarmento

Characteristics of the equine embryo and fetus from days 15 to 107 of pregnancy

In spite of numerous, substantial advances in equine reproduction, many stages of embryonic and fetal morphological development are poorly understood, with no apparent single source of comprehensive information. Hence, the objective of the present study was to provide a complete macroscopic and microscopic description of the equine embryo/fetus at various gestational ages. Thirty-four embryos/fetuses were aged based on their crown rump length (CRL), and submitted to macroscopic description, biometry, light and scanning microscopy, as well as the alizarin technique. All observed developmental changes were chronologically ordered and described. As examples of the main observed features, an accentuated cervical curvature was observed upon macroscopic examination in all specimens. In the nervous system, the encephalic fourth ventricle and the encephalic vesicles forebrain, midbrain, and hindbrain, were visualized from Day 19 (ovulation = Day 0). The thoracic and pelvic limbs were also visualized; their extremities gave rise to the hoof during development from Day 27. Development of other structures such as pigmented optical vesicle, liver, tail, cardiac area, lungs, and dermal vascularization started on Days 25, 25, 19, 19, 34, and 35, respectively. Light and scanning microscopy facilitated detailed examinations of several organs, e.g., heart, kidneys, lungs, and intestine, whereas the alizarin technique enabled visualization of ossification. Observations in this study contributed to the knowledge regarding equine embryogenesis, and included much detailed data from many specimens collected over a long developmental interval.

Transplantation of human immature dental pulp stem cell in dogs with chronic spinal cord injury

Purpose: To investigate the therapeutic potential of human immature dental pulp stem cells in the treatment of chronic spinal cord injury in dogs. Methods: Three dogs of different breeds with chronic SCI were presented as animal clinical cases. Human immature dental pulp stem cells were injected at three points into the spinal cord, and the animals were evaluated by limb function and magnetic resonance imaging (MRI) pre and post-operative. Results: There was significant improvement from the limb function evaluated by Olby Scale, though it was not supported by the imaging data provided by MRI and clinical sign and evaluation. Conclusion: Human dental pulp stem cell therapy presents promising clinical results in dogs with chronic spinal cord injuries, if used in association with physical therapy.

Embryonic Development of Endoderm in Chicken (Gallus gallus domesticus)

The poultry industry is a sector of agribusiness which represents an important role in the countrys agricultural exports. Therefore, the study about embryogenesis of the domestic chicken (Gallus gallus domesticus) has a great economic importance. The aim of this study was to evaluate embryonic development of the endoderm in chicken (Gallus gallus domesticus). Forty fertilized eggs of domestic chickens, starting from the 1st day of gestation and so on until the 19 days of the incubation were collected from the Granja São José (Amparo, SP, Brazil). Embryos and fetus were fixed in 10% formaldehyde solution, identified, weighed, measured, and subjected to light and scanning electron microscopy. The endoderm originates the internal lining epithelium of the digestive, immune, respiratory systems, and the organs can be visualized from the second day (48 h) when the liver is formed. The formation of the digestive system was complete in the 12th day. Respiratory system organs begin at the fourth day as a disorganized tissue and undifferentiated. Their complete differentiation was observed at the 10 days of incubation, however, until the 19 days the syrinx was not observed. The formation of immune system at 10th day was observed with observation of the spleen, thymus, and cloacal bursa. The study of the organogenesis of the chicken based on germ layers is very complex and underexplored, and the study of chicken embryology is very important due the economic importance and growth of the use of this animal model studies such as genetic studies. Microsc. Res. Tech. 76:803–810, 2013.

Osteogenesis in Chicken (Gallus gallus domesticus) and Expression of VEGF in this Process between 5 to 19 Days of Incubation

Poultry production is of great economic importance nowadays and it is important to constantly improve the production quality. In this context, the bird growth and adequate bone development are necessary for successful production. In this paper we evaluate the expression of VEGF and its importance in the osteogenesis process in embryonic and fetal tissues of Gallus gallus domesticus at different gestational ages. We observed that the Vascular Endothelial Growth Factor (VEGF) is essential in the formation of cartilaginous tissue and bone in the embryo and fetus of Gallus gallus domesticus.

Chorion biopsy in mongrel dogs

With the great development of the gestational studies in all of the species, we noticed the necessity of adaptations of these techniques for prenatal diagnosis in dogs. Based on this, we studied the feasibility of chorion biopsy guided by ultrasound. Our results demonstrated accuracy on the sex determination being 2 males and 12 females, as well as it would be possible to identify chromosome alteration due to the quality of samplings. Sex determination was accomplished with the identification of Y gene chromosomes in PCR technique. After the collection, fragments were prepared for light microscopy studies and revealed fetal chorion tissue, blood colloid and erythrocyte. In the whole material we found hemosiderin impregnations due to the hemolysis and to the residue of blood of the placental marginal hematomes. The submitted female dogs to this technique demonstrated normal puppy births without death.

Morphological aspects of buffaloes (Bubalus bubalis) umbilical cord

Bufalo e uma importante fonte de recurso nos rebanhos animais, apresentando uma grande participacao na agropecuaria, provendo leite, carne e forca de trabalho. O Cordao umbilical e responsavel pela troca de nutrientes materno-fetais durante a gestacao, e suas alteracoes podem comprometer o desenvolvimento fetal. Nos investigamos dez uteros gravidicos de bufalos de racas cruzadas em fases diferentes de gestacao. O periodo de gestacao e a idade fetal foram determinados pelo comprimento apice sacral, aplicando formulas previamente estabelecidas. Posteriormente mediu-se o comprimento do cordao umbilical. A rede vascular do cordao umbilical e anastomoses foram observadas por injecao ou latex de neoprene. O cordao umbilical foi estudado a partir de cortes histologicos, corados por HE, picrossirius, azul de Toluidina, orceina e reacao histoquimica de PAS. O cordao umbilical de bufalos e formado por duas arterias centrais, ducto alantoide e duas veias perifericas e apresentam forma de ampulheta. A parede da arteria umbilical e composta por grande quantidade de fibras colagenas e elasticas, fibroblastos e um grande numero de vasa vasorum. O ducto alantoide fica alocado entre as arterias e apresenta um grande numero de pequenos vasos nutritivos. Os vasos nutritivos devem ser cuidadosamente identificados para evitar-se confundi-los com vasa vasorum. O comprimento medio do cabo de cordao umbilical dos bufalos era 11.8cm (minimo de 6.8cm e maximo de 17.4cm).

Embryonic development of chicken (Gallus Gallus Domesticus) from 1st to 19th day-ectodermal structures.

Birds occupy a prominent place in the Brazilian economy not only in the poultry industry but also as an animal model in many areas of scientific research. Thus the aim of this study was to provide a description of macro and microscopic aspects of the ectoderm‐derived structures in chicken embryos / fetuses poultry (Gallus gallus domesticus) from 1st to 19th day of incubation. 40 fertilized eggs, from a strain of domestic chickens, with an incubation period of 2–19 days were subjected to macroscopic description, biometrics, light, and scanning microscopy. All changes observed during the development were described. The nervous system, skin and appendages and organs related to vision and hearing began to be identified, both macro and microscopically, from the second day of incubation. The vesicles from the primitive central nervous system—forebrain, midbrain, and hindbrain—were identified on the third day of incubation. On the sixth day of incubation, there was a clear vascularization of the skin. The optic vesicle was first observed fourth day of development and on the fifth day there was the beginning of the lens formation. Although embryonic development is influenced by animal line as well as external factors such as incubation temperature, this paper provides a chronological description for chicken (Gallus gallus domesticus) during its embryonic development. Microsc. Res. Tech. 76:1217–1225, 2013.

Rins de Baleia Minke (Baleanoptera acutorostrata): arquitetura e estrutura

Among marine mammals, whale is one of the most attention-arousing animals, especially concerning its urinary tract. This system follows the pattern of mammals with regard to its constitution, however, it differs in renal morphology and number of lobes, which, in turn, form complete reniculi, agglutinated in hundreds. This structure is supported by fibrous connective tissue, but highly capable of maintaining electrolyte balance. Six pairs of kidneys of Minke whale (Balaenoptera acutorostrata), collected in 1982, in Cabedelo, Paraiba, Brazil, in the last fishing allowed, were dissected. These kidneys were preserved in 10% formaldehyde and they presented a very large histologic layer of collagen surrounding the medullary wall. The urinary collecting duct form papillary glasses, that reach a single collecting center which discharges in the ureter. It was found that the kidney of Minke whale has a lobe characteristic, with, on average, 700 reniculi; each reniculus has anatomical and functional characteristics of a unipyramidal kidney, with an inner layer (medulla), and an outer layer (cortex), and independent irrigation, with formation of individually arcuate arteries, as observed in unipyramidal terrestrial mammals. However, the set gathering all these reniculi constitutes, in the end, a multilobular and polipyramidal kidney, contrary to the morphology of most terrestrial mammals. It was not possible to distinguish the renicular cortex structures of the Minke whale in the level of light microscopy. Through scanning electron microscopy, it was possible to visualize a cortical layer located between two fibrous capsules. This joint, in turn, consists of connective tissue, which, along with a layer of collagen and elastic fibers, separates the cortex from the medulla; the kidney glomeruli were visualized, completely taken by the glomerular vessels and arranged into several layers. One notices that the glomerular cavity is almost a virtual space into which the glomerular filtrate is drained, and it does not present a globular shape. Vascularization is increased in the medullary region. The difference between the kidneys of terrestrial and marine mammals consists in the arrangement of morphological components, favoring the organs physiology.

Avaliação da técnica de arteriografia renal guiada por fluoroscopia em suínos

The fluoroscopy–guided renal arteriography was evaluated in order to be used as an auxiliary method in investigations and as a way to experimentally induce kidney diseases in swine. The technique was effective to obtain sharp images as well as to determine the area of renal irrigation. Despite its easiness, trained professionals are required to perform it.

AVALIAÇÃO DA TÉCNICA DE ARTERIOGRAFIA CEREBRAL GUIADA POR FLUOROSCOPIA EM SUÍNOS

The cerebral arteriography is a radiologic exam for demonstration of arterial vascularization using an injection of positive contrast for visualization of blood supply. In this research six pigs were submitted to cerebral arteriography under general anesthesia and with the assistant of fluoroscopy the femoral artery was catheterized until the carotid common right artery using contrast under selective form. The aim of this work was to analyze this technique as a complementary method in cases of suspect of alterations of blood flow. This technique shows be effective to obtain nithid images and to determinate the cerebral irrigation.