Reproductive System of Brown-throated Sloth (Bradypus variegatus, Schinz 1825, Pilosa, Xenarthra): Anatomy and Histology.

In recent years, habitat degradation led to the decline of some populations of brown-throated sloth. The aim of this study was to describe morphological features of the female reproductive system of the species. The oval ovaries were partially surrounded by ovarian bursa. An external cortex and an inner medulla were present. Corpora lutea and corpora albicans together with follicles at various stages of development each with a single oocyte were found in the cortex. Uterine tubes were tortuous, tubular, travelled around the perimeter of the ovary and possessed a folded mucosa with ciliated pseudostratified epithelium. Uterus was simplex, with no horns and divided into three parts: a pear-shaped cranial segment and a long caudal uterine segment (both forming the body of the uterus) and two cervices. Uterus presented three layers: mucosa, lined by pseudostratified epithelium, muscular and serosa. The cervices connected the uterus to the urogenital sinus, a distensible cavity with longitudinal mucosal folds lined by transitional epithelium that extended from the external urethral orifice and the external uterine ostia to the vulva, which was lined by a keratinized stratified squamous epithelium. Brown-throated sloth presented a bipartite clitoris with paired crura, bodies and glandes. The presence of a double cervix and a bipartite clitoris was unique features of the species.

Gross anatomical features of the gastrointestinal tract (GIT) of blue and yellow macaws (Ara ararauna) - oral cavity and pharynx.

Morphological studies of the gastrointestinal tract (GIT) of blue and yellow macaws (Ara ararauna) are scarce. Therefore, this study aims to describe the macaw's oropharyngeal cavity in order to supply the deficiency of anatomical data and as part of a broad study of the GIT of these birds. Two male and one female adult blue and yellow macaws were anatomically dissected to expose the oropharynx. The macaw oropharynx was 'V-shaped' and flattened laterally being composed of maxillary and mandibular rhamphotheca of the beak. The tongue, lingual frenulum and laryngeal mound (containing 'spindle-shaped' glottis and prominent mucosal papillae) formed the floor of the oropharynx. The roof revealed two distinct regions separated by a 'step-like depression', whereas in the floor, the mandibular rhamphotheca was separated from the oral cavity mucosa by a large vestibulum enclosing the lingual frenulum. The palate was hard without any signs of rugae nor palatine raphe. A smooth ridge extended caudally from the choana to the common opening of the Eustachian tubes. This study, in addition to confirming the basic features of the oropharynx previously described for birds in general, provided new, unreported morphological data, some of which may be important when studying nutrition and health of these birds.

Gross anatomical features of the gastrointestinal tract (GIT) of blue-and-yellow macaws (Ara ararauna) - oesophagus to cloaca.

Morphological studies of the gastrointestinal tract of blue-and-yellow macaws (Ara ararauna) are scarce. In view of the paucity of information regarding the digestive tract of macaws, this study aims to describe the gross anatomical features (oesophagus to cloaca) as part of a broad study of the gastrointestinal tract (GIT) of these birds. Three animals (two males and one female) adult macaws were anatomically dissected from the oropharynx to the cloaca to expose the GIT. The oesophagus was identified as a muscle-membranous tube continuous with the crop, which was intimately attached to the skin. The internal longitudinal folds of the cervical oesophagus were sparser cranial to the crop and less evident compared to the portion caudal to the crop. The duodenum began in the pylorus and was grey-coloured exhibiting a large lumen. The jejunum was formed by loops in a spiral-fashion model supported by mesojejunum. The ileum was also composed by small loops and was continuous with the colo-rectum forming the large intestine, because the caeca were absent. The large intestine was short, median in position, suspended in the dorsal wall of the abdominal cavity by mesentery and ended in the cloaca. The GIT was similar to the basic patterns in birds, in general, and also presented new unreported morphological data that might be important when studying nutrition and health of the macaws.

Vascular endothelial growth factor A (VEGFA) modulates bovine placenta steroidogenesis in vitro.

Our objectives were to investigate the possible role of VEGFA in bovine placenta steroid synthesis and to determine whether cloned derived placental cells present similar responses as non-cloned ones. Placental cells from cloned (term) and non-cloned (days 90, 150, 210 and term) pregnancies were isolated and treated with VEGFA (50 ng/ml) for 24, 48 or 96 h. Progesterone (P(4)) and estrone sulfate (E(1)S) were assessed by RIA, while aromatase P450-positive cells were quantified using the point counting test. The percentages of steroidogenic and non-steroidogenic populations were determined by flow cytometry. VEGFA augmented or decreased P(4) and E(1)S concentrations as well as aromatase P450-positive cell density, depending on gestational age and time in culture. The percentage of steroidogenic cells was lower than that of non-steroidogenic ones for each culture time (P < 0.05). VEGFA treatment did not change the proportion of steroidogenic and non-steroidogenic cells. Placental cells derived from cloned pregnancies presented higher concentrations of E(1)S and P4 than the non-cloned group. However, aromatase P450-positive cells were similar between groups (P > 0.05). VEGFA treatment altered P(4) and E(1)S levels in placental cells depending on type of gestation. These results suggest that VEGFA acts locally in the bovine placenta to modulate steroidogenesis during gestation, but in a different pattern between cloned and non-cloned derived placental cells at term. Therefore, this factor can be considered an important regulator of placental development and function.

Somatic cell nuclear transfer is associated with altered expression of angiogenic factor systems in bovine placentomes at term.

Low efficiency of somatic cell cloning by nuclear transfer has been associated with alterations of placental vascular architecture. Placental growth and function depend on the growth of blood vessels; VEGF-A and bFGF are the most important factors controlling neovascularization and vascular permeability in the placenta. We hypothesize that the VEGF-A and bFGF systems are disrupted in placentomes from cloned animals, contributing to the placental abnormalities that are common in these clones. We determined mRNA expression and protein tissue localization of VEGF-A, bFGF, and their receptors in placentomes from cloned and non-cloned bovine fetuses at term. Real-time RT-PCR revealed that VEGFR-2 mRNA was increased in cloned male-derived placentomes, while mRNA of bFGF and its receptors were decreased in placentomes of cloned females. VEGF-A system proteins were found to be located in placentomal endothelial, maternal and fetal epithelial and stromal cells; there was a variable pattern of cellular distribution of these proteins in both cloned and non-cloned animals. Alterations in the expression of VEGF-A and bFGF systems suggest that angiogenic factors are involved in abnormal placental development in cloned gestations, contributing to impaired fetal development and poor survival rates.

The 'beneficial' adipokines in reproduction and fertility.

The objective of this study was to review the available information on the signaling proteins produced by adipose tissue in the context of their role in regulating reproductive processes, including ovarian and uterine function. It is well known that both obesity and excessive leanness are associated with reproductive dysfunction. Adipokines are cytokines predominantely or exclusively expressed by adipose tissue that circulate and affect target tissues. Four known adipokines, adiponectin, visfatin/PBEF, omentin and vaspin, all increase tissue sensitivity to insulin, and are thus described as 'beneficial'. There is strong support for a role for adiponectin in the function of the ovary and placenta. There is evidence for direct effects of this adipokine on the late stages of folliculogenesis, and additive interactions of adiponectin with insulin and gonadotropins in inducing periovulatory changes in ovarian follicles. In addition, clinical and genomic studies associate hypoadiponectinemia with obesity-related reproductive disorders, including the polycystic ovarian syndrome. The roles for visfatin/PBEF, omentin and vaspin in reproduction remain to be established. The conclusion thus drawn is that the expression of insulin-sensitizing adipokines varies with adipose abundance. These adipokines have demonstrated both the potential effects on ovarian function and the possible effects on the formation of the placenta, acting through multiple mechanisms.

Fator de crescimento fibroblástico básico e seus receptores em relação à atividade proliferativa na placenta bubalina em diferentes fases da gestação / Basic fibloblast growth factor and its receptors in relation to proliferative activity in the buffalo placenta during gestation

Estudou-se a distribuição espaço-temporal do fator de crescimento fibroblástico básico (bFGF), do receptor 1 do fator de crescimento fibroblástico (FGFR1) e do receptor 2 do fator de crescimento fibroblástico (FGFR2) na placenta bubalina, correlacionando-a à proliferação celular. Para a detecção do bFGF, FGFR1, FGFR2 e antígeno Ki-67, colheram-se 12 placentas de búfalas nos terços inicial, médio e final da gestação, em abatedouros, e realizaram-se testes de imunoistoquímica. Detectou-se e avaliou-se a expressão do bFGF, do FGFR1, do FGFR2 e do antígeno Ki-67 ao longo da gestação. No compartimento fetal da placenta, observaram-se correlações positivas entre a expressão do bFGF e Ki-67, entre FGFR1 e Ki-67 e entre FGFR2 com Ki-67 (r=0,313, 0,358 e 0,384, respectivamente). No epitélio e estroma maternos observaram-se altas correlações entre FGFR1 e Ki-67 (r=0,739 e r=0,511, respectivamente). Os resultados sugerem envolvimento do bFGF, FGFR1 e FGFR2 na proliferação do trofoblasto enquanto no compartimento materno da placenta bubalina apenas o FGFR1 atuaria como modulador dessa atividade.

The space-temporal expression of basic fibroblast growth factor (bFGF), fibroblast growth factor receptor 1 (FGFR1) and fibroblast growth factor receptor 2 (FGFR2) in buffalo placenta and correlation to proliferative activity was studied. For the localization of bFGF, FGFR1, FGFR2 and Ki-67, 12 buffalo placentas from initial, middle and final gestational thirds were collected and immunohistochemistry tests were performed. Expression of bFGF and its receptors was detected and analyzed from the initial third until the end of gestation. In the fetal compartment, positive correlations were observed between the expression of bFGF and Ki-67, FGFR1 and Ki-67, besides FGFR2 and Ki-67 (r=0.313, 0.358 and 0.384, respectively). High correlations were found between FGFR1 and Ki-67 in maternal epithelium and stroma (r=0.789 and r=0.511, respectively). The results suggest that bFGF, FGFR1 and FGFR2 may be involved in the modulation of trophoblast proliferation, whereas maternal compartment proliferation in the buffalo placenta would only be modulated by FGFR1.

VEGF system expression in different stages of estrous cycle in the corpus luteum of non-treated and superovulated water buffalo.

Water buffaloes are easily adaptable animals, whose raising and economical exploitation have been growing in the last three decades all over the world. Hyperstimulation of ovarian function in this species is a common technique aiming to improve reproductive performance. Superovulatory treatment affects corpus luteum (CL) function, which is highly correlated to angiogenic process. The aim of this study was therefore to assess the temporal protein and mRNA expression of VEGF and its receptors in the CL of non-treated and superovulated buffaloes. For that purpose blood samples and CL from 36 healthy (30 untreated, groups 1-5, and 6 superovulated, group 6) non-pregnant buffaloes were collected and the samples were divided into 6 groups according to the age of CL. Plasma samples were submitted to RIA to measure progesterone concentration and CL were subjected to immunohistochemistry and real time PCR for VEGF (vascular endothelial growth factor), Flt-1 (fms-like tyrosine kinase receptor 1) and KDR (kinase insert domain containing region). The VEGF system protein and mRNA expression during CL life span of untreated animals showed a specific time-dependent profile, although protein did not always reflect mRNA concentrations. VEGF expression in luteal cells was high correlated to plasma progesterone levels. Superovulated CL showed a significant increase of the VEGF-system protein and a significant decrease of mRNA expression compared to untreated animals in the same stage of the oestrous cycle. We conclude that VEGF, Flt-1 and KDR protein and mRNA expression in buffalo CL is dependent of estrous cycle stage and superovulatory treatment is able to increase the translation rate of this system.