José Manoel dos Santos

Macroscopic and Microscopic Anatomy of the Oviduct in the Sexually Mature Rhea (Rhea americana)

The morphological characteristics of the oviduct of 12 sexually mature rheas (Rhea americana) were studied. Only the left oviduct is developed as a long tube with a length of 122 ± 23.1 cm, and is subdivided into infundibulum (15.2 ± 4.0 cm), magnum (63.3 ± 9.4 cm), isthmus (5.6 ± 3.1 cm), uterus (16.0 ± 4.2 cm) and vagina (11.5 ± 1.4 cm). The mucous membrane of the oviduct, as a whole, possesses luminal folds covered by ciliated columnar epithelium with secretory cells. The infundibulum part presents a cranial opening with thin and long fimbriae with few tubular glands in caudal tubular portion. In the magnum, the largest portion of the oviduct, the folds are thicker and are filled with tubular glands. The isthmus is short and presents less bulky folds and a few tubular glands. A bag‐shaped uterus in the cranial area shows thin folds, and in the caudal region (shell gland) more ramified folds with few tubular glands. The vagina has long luminal folds and a thick muscular tunic; no glands with sperm‐storage characteristics have been observed. In conclusion, the oviduct in sexually mature rhea has morphological similarities with the other species of birds already described; however it presents its own characteristics to produce a big egg.

Development of bovine embryos derived from reproductive techniques.

Assisted reproduction techniques have improved agricultural breeding in the bovine. However, important development steps may differ from the situation in vivo and there is a high mortality rate during the first trimester of gestation. To better understand these events, we investigated the development of embryos and fetal membranes following fixed-time AI (FTAI), IVF and nuclear transfer (NT). The onset of yolk-sac development was not normal in cloned embryos. Later steps differed from conditions in vivo in all three groups; the yolk-sac was yellowish and juxtaposed with the amniotic membrane. Vascularisation of the chorioallantoic membrane was relatively late and low in NT gestations, but normal in the others. The overall development of the embryos was normal, as indicated by morphology and regression analysis of growth rate. However, NT conceptuses were significantly smaller, with the livers in some embryos occupying the abdominal cavity and others exhibiting heart abnormalities. In conclusion, the yolk-sac and the cardiovascular system seem to be vulnerable to morphogenetic alterations. Future studies will focus on gene expression and early vascularisation processes to investigate whether these changes may be responsible for the high incidence of intrauterine mortality, especially in clones.

A morphological analysis of the transition between the embryonic primitive intestine and yolk sac in bovine embryos and fetuses

The yolk sac (YS) is the main source of embryonic nutrition during the period when the placenta has not yet formed. It is also responsible for hematopoiesis because the blood cells develop from it as part of the primitive embryonic circulation. The objective of this study was to characterize the transitional area between the YS and primitive gut using the techniques of light microscopy, transmission electron microscopy, and immunohistochemistry to detect populations of pluripotent cells by labeling with Oct4 antibody. In all investigated embryos, serial sections were made to permit the identification of this small, restricted area. We identified the YS connection with the primitive intestine and found that it is composed of many blood islands, which correspond to the vessels covered by vitelline and mesenchymal cells. We identified large numbers of hemangioblasts inside the vessels. The mesenchymal layer was thin and composed of elongated cells, and the vitelline endodermal membrane was composed of large, mono‐ or binucleated cells. The epithelium of the primitive intestine comprised stratified columnar cells and undifferentiated mesenchymal cells. The transitional area between the YS and the primitive intestine was very thin and composed of cells with irregular shapes, which formed a delicate lumen containing hemangioblasts. In the mesenchyme of the transitional area, there were a considerable number of small vessels containing hemangioblasts. Using Oct4 as a primary antibody, we identified positive cells in the metanephros, primordial gonad, and hepatic parenchyma as well as in YS cells, suggesting that these regions contain populations of pluripotent cells. Microsc. Res. Tech. 76:756–766, 2013.

Morfologia do ovário da ema (Rhea americana)

The ovarian morphology of the sexually mature rhea (Rhea Americana) is described. Ovaries from 24 adult rheas in their reproductive age were collected in the slaughterhouse. Follicular diameters (n = 18) were measured and samples (n = 6) were fixed in 10% formaldehyde with 0.1M phosphate buffer at pH 7.4 for light microscopy. Results showed that the left ovary occupied the dorsal portion of the celomatic cavity in contact with the cranial portion of the left kidney and the suprarenal gland, being supported in the cavity through the mesovary. On the free surface of the ovary 72.4±17.09 follicles in different phases of development and 30.4±3.65 atretic follicles were observed. The follicles were linked to the ovarian surface by the follicular stalk and had a wide band surrounding its surface, the Stigma folliculare. Histologically, the ovary is constituted by a medulla, composed by connective tissue and vessels, and by a cortex with oocytes and follicles. The follicular wall is composed by the Theca externa and Theca interna, Stratum granulosum and the Zona radiata. The ovary surface is covered by a cubic epithelium, the germinal epithelium, on the connective tissue of the Tunica albuginea. The morphologic characteristics of the ovary of the rhea are due to the egg size in this species and generally similar to other birds.

Morfologia dos órgãos genitais masculinos e da cloaca da ema (Rhea americana americana)

The rhea (Rhea americana americana) is a bird that belongs to the group of the Ratitas, order Rheiforme and family Rheidae. Macroscopic and microscopic morphology of the male genital organ (testes, epididymis, deferent ducts, and phallus) and the cloaca were analyzed in 23 emas, four chicken (2 weeks old), young (3 to 10 months old), and twelve adult ones (3 years old), from Cooperativa Emas do Brasil, RS and from CEMAS, Mossoro, RN. The testis of rhea had elongated shape and were located inside coelomatic cavity, in dorsal region of abdominal cavity, with medium length and width of 7.6±1.2cm and 2.6±0.7cm at adult animals; 4.5±1.5cm and 0.9±0.4cm at young animals; and 0.8±0.3cm, and 0.2±0.1cm at chicken. The testis were recovered by the tunica albuginea and its parenchyma had seminiferous tubules composed by spermatogenic epithelium and by sustentation cells, and also interstitial tissue, with interstitial endocrine cells, connective tissue and vessels. At the adult animals were observed all the cells from spermatogenic lineage, whilst at the youngs with 3 months the seminiferous tubules had a smale lumen with spermatogonia and undifferentiated sustentacular cells. The efferents ductus were composed by a cubic ciliated epithelium, while the epididimydis duct had a columnar epithelium. The epididymis was elongated and fusiform closely to medial testis board. The deferent duct had sinuous stretch at adult animals, rectilineae at young animal, convolute at its medium portion, decreasing its sigmoid shape at caudal portion, next to cloaca. The epithelium was pseudostratified ciliated, irregular lumen at adult animal, and circular at young animal, closely with urether. The cloaca was divided into three segments: coprodeum, urodeum and proctodeum. At urodeum the deferent ducts discharged into papillas at the ventral side wall, next to fibrous phalluss insertion. The phallus was a lymphatic fibrous organ, located at ventral wall, at the cloaca floor, and was composed by two portions: one rigid forked and twisted, and another simple spiraled and flexible, which normally was inverted. In forced exposition, the phallus had 14 cm in length. In a general way the Rhea genital organs shared the morphology from others birds, mainly those described to the ostrich.

Bovine meroanencephaly and gastroschisis: a macro and microscopic study.

Congenital malformations correspond to one of the main causes of embryonic loss during the gestational process. They result from interaction of several factors such as multifactor heredity, chromosomal and genetic alterations and environmental agents; however, unknown aetiology also can be present. In this article, we have used 10 embryos, from a frigorific area of Dracena, SP, Brazil, which were fixed in Bouin solution for a macro‐ and micro‐scopic description. We could verify the presence of an encephalic tissue mass on the embryo’s dorsal cranial area, resulting from the non‐formation of part of the cranial cap and from the non‐closing of cephalic neuropore and consequent neuroepithelial cells disorganization. In the abdominal area, the embryos did not show the complete fusion of the body lateral pleats during the abdominal wall formation, and the liver extruded into the amniotic cavity without involvement of the intestine.

Development of Respiratory Tract from Bovine Embryos

We studied the development of respiratory tract in bovine embryos by light microscopy and transmission electronic microscopy. This process was observed formation of laryngeal-tracheal tube in embryos that present crown-rump (CR) length of 9.0 mm (20/21 days of pregnancy) at around the fourth gestational week; the organ wall appears to be formed of epithelium comprising several cell layers and supported by mesenchyme. Within the lungs, the areas subjacent to epithelium present condensed mesenchyme, while more distal areas loose mesenchyme, in which blood vessels beginn to form, as the organ is in a pseudo-glandular phase. Ultra-structurally, the mesenchyme cells present irregular shapes, having a stellar or fusiform appearance and are united by desmosomes, where the cytoskeleton attaches to the cellular membrane, forming a connection. The bifurcation of trachea caudal portion in the main bronchia is simultaneous to the appearance of the tracheal bronchi, during the fifth gestational week.

Morfologia e funcionalidade do pneumócito tipo II e sua relação e variação com a idade gestacional em bovinos

The aim of this study was to characterize the presence of type II pneumocyte and the beginning of the surfactant protein production in bovines to the correlated gestational age. Lungs of fetuses at 4 months gestational age were found to be in the canalicular development phase, without presence of type II pneumocytes or appearance of electrophoretic bands compatible with the presence of the surfactant protein. In fetuses at 5 months of gestational age, the lungs were at the terminal sac phase, with the presence of primitive alveolus, formed by cubical epithelium and areas formed by pneumocytes I and pneumocytes II. No electrophoretic bands compatible to the surfactants proteins were identified. In contrast, lungs of fetuses at 6 months of gestational age showed, development of terminal sac phase, with the presence of type I and type II pneumocytes. In this phase, proteic determination for the SDS - PAGE analysis showed the presence of bands between 26 to 36kDa, demonstrating SP – A production, which is the surfactant protein found in highest amount. From the 7th gestational month on, the phase of terminal sac is more evident and complex, with intense sprouting vascularization. The type I pneumocyte had a more squamous aspect and type II pneumocyte were more globular. In the SDS – PAGE analysis of the bronchial – alveolar wash, surfactant protein bands had been observed with a profile similar to that of the newborn animals. In newborn animals, lungs in alveolar phase showed the development of type I and II pneumocytes. The profile of

Efeito da ivermectina sobre a ciclicidade, gestação e desenvolvimento neonatal em ratos

O objetivo do presente trabalho foi avaliar o ciclo estral, gestacao e lactacao de ratas tratadas com ivermectina. 82 ratas albinas foram divididas em sete grupos. Os animais receberam agua destilada (GI) ou diferentes doses de ivermectina, por via oral (GII=0,5; GIII=1,0; GIV=2,0; GV=4,0; GVI=8,0 e GVII=10,0 mg/kg). Os animais foram tratados por 45 dias, com ivermectina a cada tres dias, totalizando 15 aplicacoes. Apos esse periodo foi realizado exame colpocitologico durante 15 dias consecutivos. Ao final, quatro animais de cada grupo foram sacrificados e ovarios e uteros retirados e processados para avaliacao histologica. Os animais restantes foram acasalados e tratados com ivermectina, nas doses correspondentes a cada grupo, no 1o, 4o, 7o, 10o, 13o e 16o dias de gestacao. Ao nascimento, os neonatos foram contados, analisados quanto a existencia de defeitos congenitos, mortalidade e pesados ate o 15o dia de lactacao. Durante a lactacao, as matrizes receberam novamente ivermectina no 1o, 4o, 7o, 10o e 13o dias. Nossos resultados mostraram que os animais dos grupos II, III, IV, V, VI e VII apresentaram maior incidencia de estro em relacao a GI. Quanto a histopatologia, os grupos tratados com a ivermectina apresentaram maior concentracao de glândulas endometriais hiperplasicas. O tratamento nao afetou tempo de gestacao, numero de neonatos, mortalidade ou defeitos congenitos. Na lactacao observamos perda de peso na prole das matrizes tratadas com ivermectina. Pode-se concluir que a ivermectina, aumenta a incidencia de estro e nao deve ser indicada para uso em animais lactantes.

MORPHOLOGICAL ASPECTS OF THE ENDOMETRIUM OF PERSISTENT ESTROUS RATS INDUCED BY CONTINUOUS LIGHT SUBMITTED TO OOFORECTOMY AND TREATED WITH OESTROGEN AND PROGESTERONE

Los principales objetivos de este trabajo son analizar las modificaciones que ocurren en el endometrio de ratas en estro persistente inducida por luz continua y observar la respuesta endometrial a administracion de estrogenos y/o progestagenos sobre el endometrio, en esas condiciones experimentales. Los resultados mostraron que el estroma endometrial de ratas sometidas a luz continua presentaba caracteristicas tipicas de la fase de estro, siendo que los epitelios superficial y glandular presentaban areas de estratificacion, dependientes de las hormonas ovaricas y que tales caracteristicas desaparecen despues de la ooforectomia. La ooforectomia no bloquea el efecto inducido por la luz, ya que despues de la administracion del estrogeno, el endometrio presentaba las mismas caracteristicas de los animales en estro persistente. Cuando se administro el acetato de medroxiprogesterona juntamente con el estrogeno, hubo un bloqueo de las areas de estratificacion, indicando que la progesterona es moduladora del estrogeno. En este trabajo concluimos que el estro persistente inducido por la luz continua, depende de las hormonas ovaricas y que la principal hormona es estrogeno. Tambien se observo que la progesterona bloquea las inducciones provocadas por el estrogeno