Many species of opossums are created and used in laboratories, opening a wide field for studying and acquiring knowledge about the habits, diseases, diet and reproduction of these animals. The research aimed at describing the macroscopic and microscopical morphology of the trachea and larynx of opossums. In this study, five opossums (Didelphis sp.) were used. The trachea and larynx of the opossums were extracted, measured and processed by histology routine and dyed with Hematoxiline eosine, Picrosirius and Masson´ Trichrome. The larynx can be divided into: cricoid in a "V"-like shape, thyroid in a shield-like shape, arytenoid in shell-like shape, and epiglottis shaped like sheets, the first three structures showed hyaline cartilage, and the last structure showed elastic cartilage. The trachea showed a cylindrical form and it consists of 25 cartilaginous incomplete rings in a "C"-like shape, similar to amphibians, snakes, lizards and pigs; and different from domestic animals

O quati (Nasua nasua, Linnaeus, 1766), de hábito diurno, e o mão-pelada (Procyon cancrivorus, G. Cuvier, 1798), de hábito crepuscular e noturno, são espécies de mamíferos terrestres, pertencentes à família dos procionídeos, que são amplamente encontrados no território brasileiro. Para este trabalho foram utilizados três quatis e dois mãos-peladas adultos provenientes do Criatório Científico-Cecrimpas do Centro Universitário da Fundação de Ensino Octávio Bastos (Ibama 02027.003731/04-76) dos quais foram obtidas amostras de tecido das glândulas salivares parótidas coradas em H.E. para microscopia de luz. Constatou-se que a glândula parótida dos quatis e mãos-peladas possui posicionamento semelhante à dos demais carnívoros domésticos, com seus ductos se abrindo no vestíbulo oral, próximo à altura do quarto dente pré-molar superior, e que histologicamente as glândulas parótidas dos quatis e mão-peladas são constituídas por ácinos serosos, assemelhando-se à maioria dos animais domésticos, homens e roedores e diferindo dos resultados encontrados nos cães jovens, cordeiros e outros carnívoros como o furão que possuem ácinos mistos, e de alguns carnívoros, que apresentam ácinos serosos e mucosos. Conclui-se que o fato da constituição serosa dos ácinos das glândulas parótidas dos quatis e mão-peladas se assemelhar pode ser devido ao hábito alimentar onívoro compartilhado pelas duas espécies.

RESUMO.-A capivara (Hydrochoerus hydrochoeris), um roedor silvestre típico no continente Sul-americano, é utilizada como fonte de alimento em toda a sua região de ocorrência, sendo um importante componente na dieta de povo indígena e população rural do Brasil. O conhecimento da morfologia fornece bases para outras áreas de atuação, bem coamo, para o manejo biológico de animais silvestres. Devido à escassez na literatura de estudos anatômicos e morfológicos do aparelho respiratório da capivara, o objetivo deste trabalho é analisar os órgãos deste aparelho, macro e microscopicamente, para que possamos adquirir melhor conhecimento básico e compará-lo com o de animais da mesma subordem (Histricomorfos) e com outras espécies de mamíferos. Vimos que o aparelho respiratório da capivara é formado pelas narinas, fossas nasais, cavidade nasal, seios paranasais, faringe, laringe, traqueia e pulmões. O nariz se localiza em plano nasal com as narinas dispostas lateralmente. A maior parte da cavidade nasal está ocupada pelas conchas nasais, que se apresentam como estruturas em formato de espiral, com seus respectivos meatos. A laringe está delimitada por suas cartilagens e está em comunicação com a traqueia. A traqueia é um tubo cartilaginoso flexível e membranoso, com anéis incompletos em formato The capybara, a wild rodent typical of the South American continent, is a source of food in all regions of its occurrence and is an important component in the diet of indigenous people and the rural population of Brazil. Knowledge of morphology is basic for the biological management of wild animals. Due to the scarcity of literature on morphological and anatomical studies of the respiratory tract of capybara, the aim of this study is to analyze the organs of this apparatus, macro and microscopically, so we can acquire better basic knowledge and compare it with that of animals of the same suborder (Histricomorpha) and with other species of mammals. We have seen that the respiratory tract of capybara is formed through the nostrils, nasal, nasal cavity, paranasal sinuses, phisarynx, larynx, trachea and lungs. The nose is located in nasal plan with nostrils arranged laterally. The largest part of the nasal cavity of the capybara is occupied by the turbinates, which performe as spiral--shaped structures, with their respective meati. The larynx is bounded by cartilage and in communication with the trachea. The trachea is a flexible cartilaginous and membranous tube, with incomplete rings in the shape of a "C", which is bifurcated in its terminal part, forming the tracheal carina. The lungs of capybaras are in pairs, right (with four lobes) and left (with two lobes), located in the chest cavity. The bronchial tree of capybara is formed by primary bronchi and by a sequence that includes intrapulmonary bronchi, bronchioles, terminal bronchioles, and respiratory bronchioles.

ABSTRACT

The androgen/estrogen balance is essential for normal sexual development and reproduction in mammals. Studies performed herein investigated the potential for estrogen synthesis in cells of the testes of a hystricomorph rodent, The study characterized the expression of the key enzymes responsible for estrogen and androgen synthesis, cytochromes P450 aromatase (P450arom), 17α-hydroxylase/17,20-lyase (P450c17) respectively, as well as the redox partner NADPH cytochrome P450 oxido-reductase (CPR) required to support electron transfer and catalysis of these P450s, by immunohistochemistry (IHC) and quantitative polymerase chain reaction (qPCR) analysis, throughout postnatal sexual development. Testes (immature, pre-pubertal, pubertal and post-pubertal) were collected, fixed for IHC (CYP19, CYP17 and CPR) and stored frozen for qPCR for the relevant gene transcripts ( and ). Expression of P450c17 was significantly elevated at the pre-pubertal and pubertal stages. Based on IHC, P450c17 was expressed only in Leydig cell clusters. The expression of P450arom was detectable at all stages of sexual development of IHC data suggest that estrogen synthesis was not restricted to somatic cells (Leydig cells/Sertoli cells), but that germ cells may also be capable of converting androgens into estrogens, important for testicular function and spermatogenesis.

Present research was carried out in order to perform the monitoring of development, recognizes the type of tissue and describes histological and cellular changes of the vaginal closure membrane (VCM) throughout pregnancy in Galea spixii. The results showed that at 20 days of gestation (DG), the VCM occludes completely the external vaginal ostium. Microscopically, the VCM presented juxtaposed cells, derived from the stratum germinative of the stratified epithelium of vaginal mucosa at 20 DG and areas with cell clusters with the presence of intercellular spaces in the final stages of pregnancy (40-50 DG). At 0 DG, the stratified epithelium of vaginal mucosa presented all strata but at 20 DG presented stratified epithelium without the stratum corneum and stratum granular and showed communicant junctions by desmosomes and interdigitations in the cell membrane compound the VCM. Gradually from 40 to 50 DG the stratum germinative became barely perceptible. Many cells showed apoptotic nuclei and emerged many intercellular spacing. So, the interdigitations and desmosomes were not observed. Here, it was demonstrated for the first time that the VCM is formed after the extinction of the stratum granular and corneum of the vaginal mucosa epithelium, with the proliferation of the cells of stratum germinative and communication and junction through desmosomes and interdigitations of these cells. At the end of pregnancy, cellular apoptosis; the spread of stratum germinative; and, absence of cellular communication and junction may be responsible for the weakening of the VCM and may assist the process of rupture of this membrane.

The Spix’s yellow toothed (SYT) cavy is a species of rodent that lives in Caatinga vegetation of northeast Brazil. The SYT is utilised as a protein source by inhabitants of that region and has zootechnic potential. SYT cavies have been bred in captivity for studies related to reproductive biology. The presence of a penile clitoris trespassed by the urethra was described in the adult female. The aim of this research is describe sexual differentiation events in the male and female conceptus and relate molecular mechanisms of androgen and oestrogen metabolism of the placenta with the differentiation of external genitalia. Conceptuses after 15, 22, 30, 40, >50 (full term) days of gestation (DG; n = 9 males and 9 females at each gestational period) from 30 pregnant females, which were paired with 10 males, were used. After detection of copulation, the above described DG were awaited prior to the day of euthanasia. We performed anatomical description and light and scanning electron microscopy on the genital organs in the conceptus; concentration of testosterone (T) and oestradiol (E) by radioimmunoassay in the pregnant females; and described the immunoreactivity (by immunoblotting and immunohistochemistry) of enzymes: cytochrome P450 aromatase, cytochrome P450c17, 17-β-HSD, and 3-β-HSD in placentas of male and female conceptus. The genital organs emerge from a pair of undifferentiated gonads and a genital tubercle at 15 DG. These gonads differentiate into a pair of testicles or a pair of ovaries at 22 DG. The other internal genital organs arise from the urogenital sinus and Müllerian ducts in females or Wolffian ducts in males after 22 DG. The undifferentiated genital tubercle forms the penis in males with the urethra channeling at 30 DG. In females, the urethra channeling is complete after 40 DG with the closure of the urethral groove, and at >50 DG the clitoris has characteristics of a pseudo-penis. Those that are pregnant undergo an increase of E (from 5.456 ± 1.599 pg mL–1 at 22 DG to 107.186 ± 15.966 pg mL–1 at >50 DG) and T (from 122.444 ± 15.799 pg mL–1 at 22 DG to 718.555 ± 67.407 pg mL–1 at >50 DG) concentrations during the gestational period. The concentration of T was a minimum 5-fold higher than the E concentration at the moment of external sexual differentiation. The placentas from the male and female conceptus are immunoreactive for the enzyme 3-β-HSD producing progesterone throughout pregnancy, but these placentas are not immunoreactive for the oestrogen-producing enzyme cytochrome P450 aromatase throughout pregnancy. Conversely, the cytochrome P450c17 and 17-β-HSD enzymes are immunoreactive in the placentas of the male and female conceptus throughout pregnancy, producing androgen hormones. The absence of enzymes that produce oestrogen hormones in the placenta of SYT cavies indicate that testosterone from pregnant reaches the fetal circulation, and associated with the presence of enzymes that produce androgens, may act to increase androgen hormone concentration in the pregnant, which may act in the virilization process of the female external genitalia.

outras espécies já descritas na literatura. Utilizou-se dentes das três espécies para analises macroscópicas, microscópicas e ultraestrutural e os resultados correlacionados com os obtidos com outras espécies citadas na literatura. Chegou-se a conclusão de que: as três espécies apresentaram uma fórmula dentária idêntica, chegando a um total de 32 dentes, expressa na fórmula 2x: incisivos 2/2; caninos 1/1; pré-molares 3/3 e molares 2/2, estes são classificados como diplodontes, anelodontes, bunodontes, e braquiodontes. PALAVRAS-CHAVE: alimentação, calitriquídeos, fórmula dentaria de primatas, odontologiaMorphofunctional classification of teeth of marmosets-tufted white (Callithrix jacchus, Callitrichidae), marmosets-tufted black (C. penicillata), and marmosets white-face (C. geoffroyi) ABSTRACT A study was conducted to analyze the morphology of the teeth of white-tufted-ear-marmoset (C. jacchus) black-tufted-earmarmoset (C. penicillata) and marmosets-white-faced (C. geoffroyi), to compare them among themselves and with other species described in the literature. Teeth of the three species were submitted to macroscopic, microscopic and ultrastructural analyzes. The results were correlated with those of other species. We concluded that: the three species have a similar dental formula, reaching a total of 32 teeth, expressed in the formula 2x: incisors 2/2; canines 1/1, pre-molars 3/3 and molars 2/2, ich are classified as diplodont, anelodont, bunodont and brachyodont.