Steroidogenesis during Dry and Wet Season of Free-Living Male Scorpion Mud Turtle (<em>Kinosternon scorpioides</em>)

This study aimed to elucidate seasonal reproductive patterns by associating the immunolocalization of the steroidogenic enzymes responsible for estrogen and androgen synthesis, cytochromes P450 aromatases (P450 arom), 17-hydroxylase/17,20-lyase (P450c17) respectively, as well as the redox partner NADPH cytochrome P450 oxido-reductase (CPR) in the male mud turtle (Kinosternon scorpioides). The animals were collected at São Bento, Maranhão, Brazil. Testicles and epidydimes from 38 adult animals were characterized by immunohistochemistry (IHC) and western blotting. Data were analyzed in two seasons: dry and wet season. In addition, the gonadosomatic index, morphometry, concentrations of testosterone, corticosterone, and estradiol were analyzed. The changes in biometrics, cell morphometry, and testicular steroidogenesis between the wet and dry seasons support that estrogen produced by the Leydig cells might influence germ cell production during spermatogenesis, and the expression of the enzymes P450 arom and P450c17 in the Leydig cells that play a role in testicular quiescence. We found that the P450arom, P450c17, and CPR are present in the testes and epididymides at both seasons. These findings support a state of male reproductive quiescence during the dry season and active spermatogenesis in the wet season

Morphology and Involution of the Yolk Sac during Early Gestation Bovine (Bos indicus)

Background: The bovine yolk sac derives from visceral endoderm and its development occurs between days 18-23 of gestation. The study of this membrane is important for comparative data and has already been performed in rodents, sheep and in cattle, especially Bos taunts. In species Bos indicus the yolk sac has not quite been studied and is believed that there are morphological differences between these species. The yolk sac undergoes a process of involution and degeneration during embryonic development and none vestige of it is found in late gestation. The period in which occurs the involution of the yolk sac coincides with the period of increased pregnancy loss in cattle, and changes in the morphology of this membrane may indicate the reasons for such high loss rates. Thus, considering that the yolk sac is important for embryonic circulation and metabolic transmission, besides participating actively in the process of cattle placentation, this study aimed characterize morphologically the involution of the bovine yolk sac. Materials, Methods & Results: The early gestational period was determined between days 20 and 70 post-insemination (p.i), according to the exterior characteristics of embryo/fetus. For macroscopic analyzes the uterus was dissected to expose the fetal membranes and subsequently the embryo/fetus was photographed. The samples were fixed for light microscopy and transmission electron microscopy. The yolk sac that emerges from the ventral part of the embryo was prominent and composed by a central part with two thin peripheral projections of different lengths. The bovine yolk sac with about 9 cm on day 25 p. i. of pregnancy permanently decreased its total length during this study. Histologically, the yolk sac is composed of three cell layers: the mesothelium, the mesenchyme and the endoderm. In mesenchyme are found blood islets. In the endoderm are formed cells invaginations toward the mesenchyme originating small canaliculi. The ultrastructure of yolk cells presented many mitochondria, rough endoplasmic reticulum, vesicles, euchromatin and the presence of two nucleoli, Discussion: The real first blood circulation in the bovine is attached with the development of yolk sac, differently from other membranes, such as the corium, that does not present evidence of vascularization by the age of 20-30 days. The erythroblasts found in the yolk sac are related to vasculogenesis and the process of differentiation of blood cells during the erythropoiesis. It could be observed on the histology of the yolk sac, in embryos of 30-50 days old, the presence of canaliculi and small folds of the epithelium. The canaliculi collapse is associated with the degeneration of the endoderm wall of the yolk sac. The organelles present in the endoderm cells of the yolk sac are associated with the function of protein metabolism and in the exchange of substances between the mesenchyme and the mesothelium, For these findings, could be observed that the yolk sac epithelium is found active until the 50th day of gestation, and thereafter regresses. However, remnants of this membrane may be present until the 70th day, These features may represent a presence of an active chorionvitelline placenta in this period responsible for the maintenance of pregnancy whereas the chorioallantoic placenta is not definitively established.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2008/58811-6]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP

ISOLATION AND CHARACTERIZATION OF STEM CELLS FROM YOLK SAC DOMESTIC PORCINE (Sus scrofa)

Embryonic stem (ES) cells are pluripotent cells that are able to generate a whole organism. The ES cells give rise to rapidly dividing fetal stem (FS) cells, which are responsible for fetal growth and development. Therefore, this study aimed to analyze the cells from the yolk sac to characterize this cells as to potential as a possible source of pluripotent stem cells for future use in regenerative therapy. The yolk sac tissue was collected from the embryos in the early stage of gestation (30d) and explants from YS were plated with medium culture 15% fetal bovine serum  and incubated at 37ºC in a humidified atmosphere of 5% CO2. Trials were made for concentration and cell viability, cell growth evaluation, and the characterization by flow cytometry using specific antibodies (CD105, NANOG, CD45 and Oct-3/4), immunocytochemistry using the following antibody: CD90, CD105, CD117, vimentin, Stro-1, Oct-4, VEGF, beta tubulin, Cytokeratin and PCNA and Osteogenic, adipogenic, and chondrogenic differentiation assays. The yolk sac cells showed adherence to plastic and a spindle-like morphology, they reached confluence of 70% in about 20 days, these cells were maintained until passage 4, where later cell death occurred. These cells had similar imunofenoipagem the mesenchymal stem cells and hematopoietic cells expressing markers such as CD105, CD90, CD117, vimentin, Stro-1, Oct-4, VEGF, Beta Tubulin, Cytokeratin, Nanog and PCNA. These cells can be classified as pluripotent cells, in other words, possessed self-renewal and multi-lineage differentiation potency, which could differentiate into chondrocytes, adipocytes and osteocytes. The pYS cells would provide an ideal cell resource for regenerative medicine and tissue engineering

Morphology and Involution of the Yolk Sac during Early Gestation Bovine (Bos indicus)

Background: The bovine yolk sac derives from visceral endoderm and its development occurs between days 18-23 of gestation. The study of this membrane is important for comparative data and has already been performed in rodents, sheep and in cattle, especially Bos taunts. In species Bos indicus the yolk sac has not quite been studied and is believed that there are morphological differences between these species. The yolk sac undergoes a process of involution and degeneration during embryonic development and none vestige of it is found in late gestation. The period in which occurs the involution of the yolk sac coincides with the period of increased pregnancy loss in cattle, and changes in the morphology of this membrane may indicate the reasons for such high loss rates. Thus, considering that the yolk sac is important for embryonic circulation and metabolic transmission, besides participating actively in the process of cattle placentation, this study aimed characterize morphologically the involution of the bovine yolk sac. Materials, Methods & Results: The early gestational period was determined between days 20 and 70 post-insemination (p.i), according to the exterior characteristics of embryo/fetus. For macroscopic analyzes the uterus was dissected to expose the fetal membranes and subsequently the embryo/fetus was photographed. The samples were fixed for light microscopy and transmission electron microscopy. The yolk sac that emerges from the ventral part of the embryo was prominent and composed by a central part with two thin peripheral projections of different lengths. The bovine yolk sac with about 9 cm on day 25 p. i. of pregnancy permanently decreased its total length during this study. Histologically, the yolk sac is composed of three cell layers: the mesothelium, the mesenchyme and the endoderm. In mesenchyme are found blood islets. In the endoderm are formed cells invaginations toward the mesenchyme originating small canaliculi. The ultrastructure of yolk cells presented many mitochondria, rough endoplasmic reticulum, vesicles, euchromatin and the presence of two nucleoli, Discussion: The real first blood circulation in the bovine is attached with the development of yolk sac, differently from other membranes, such as the corium, that does not present evidence of vascularization by the age of 20-30 days. The erythroblasts found in the yolk sac are related to vasculogenesis and the process of differentiation of blood cells during the erythropoiesis. It could be observed on the histology of the yolk sac, in embryos of 30-50 days old, the presence of canaliculi and small folds of the epithelium. The canaliculi collapse is associated with the degeneration of the endoderm wall of the yolk sac. The organelles present in the endoderm cells of the yolk sac are associated with the function of protein metabolism and in the exchange of substances between the mesenchyme and the mesothelium, For these findings, could be observed that the yolk sac epithelium is found active until the 50th day of gestation, and thereafter regresses. However, remnants of this membrane may be present until the 70th day, These features may represent a presence of an active chorionvitelline placenta in this period responsible for the maintenance of pregnancy whereas the chorioallantoic placenta is not definitively established.Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2008/58811-6]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP

Effects of equine chorionic gonadotrophin on follicular, luteal and conceptus development of non-lactating Bos indicus beef cows subjected to a progesterone plus estradiol-based timed artificial insemination protocol

The aim of this study was to evaluate the effects of equine chorionic gonadotropin (eCG) on ovarian follicular responses, corpus luteum (CL) development and conceptus length on day 16 after timed artificial insemination (TAI). A total of 124 cows at day 0 (D0) received 2 mg of estradiol benzoate (EB) and the insertion of a progesterone (P4) intravaginal device. Eight days later, the device was removed, and cows received 0.15 mg of prostaglandin and 0.5 mg of estradiol cypionate (EC), and were randomly assigned to 1 of 2 treatments: eCG (n=60), in which cows received 300 U of eCG; and control (n=64). Cows were TAI 48 h after P4 device removal. The diameter of the largest follicle (LF) present on D8 and D10 and of CL on D15 and D26 were measured. Conceptus recovered rate, conceptus length, CL diameter and weight were determined at slaughter on D26. Plasma P4 concentration was determined on D15 and D26. Follicular growth from D8 to D10 (P=0.03), the diameter of CL at D15 (P=0.03) and D26 (P=0.003) and the CL weight at day 26 (P=0.04) were greater in the eCG group than the control. However, there was no effect of eCG treatment on oestrus occurrence, conceptus recovery rate and length, or P4 concentrations on either D15 or D26. In conclusion, although eCG increases follicular responses and the diameter of the CL, this gonadotropin treatment does not influence the length of the conceptus or the P4 concentration on the subsequent oestrus cycle

Morfologia dos órgãos genitais externos do macho de cutia (Dasyprocta aguti. Linnaeus, 1766)

Thirty-thee males adult agoutis (Dasyprocta aguti) had been used, originated from the Universidade Federal do Piauí (UFPI) - Piauí State, and from the Escola Superior de Agricultura de Mossoró (ESAM) - Rio Grande do Norte State - Brazil. The purpose of the present investigation was describly the morfology of male genital organs and caracterized the histology aspects and their gross caracteristics. It was carry out an dissections of the extenal organs genital. The fragments were included in paraffin and stained with hematoxylin-eosin and Tricomy of the Masson and observed in light microscopic .The result showed that the penis is fibrocavernous with large amounts of the keratizaded structures in the their apex. In third part of the penis was evidencied an curved with form of the "U" lying. The glans was covering to keratinized epiderm with many espicules, an bone penis has been replaced the carvernous body. In the part ventral of the penis there was suburethal sac with two long projection corneus. In the Scroral region there wasn't distintict external limits with scrotum. Under of the internal layer of the prepuce, next to the preputial orifice, there was two preputial gland.Foram utilizados vinte e três cutias (D. aguti), machos, adultos, adquiridos em criatórios científicos, legalmente licenciados pelo IBAMA, da Universidade Federal do Piauí - UFPI, Teresina, PI e da Escola Superior Agrícola de Mossoró - ESAM, Mossoró, RN, com o objetivo de descrever morfologicamente os órgãos genitais masculinos externos, abordando aspectos histológicos e macroscópicos destes órgãos. Foi realizada a dissecação dos órgãos genitais externos dos espécimes. Fragmentos foram coletados e submetidos ao processamento histológico de rotina para inclusão em parafina, os quais foram cortados e corados pelos métodos de H/E e Tricômico de Masson e observados em microscópio de luz. Os resultados mostraram que o pênis destes animais possui características do tipo fibrocavernoso, com grande quantidade de estruturas queratinizadas no seu ápice. No terço médio do pênis da cutia foi evidenciado uma flexura peniana em forma de "U" deitado; a glande do pênis encontra-se revestida por uma epiderme queratinizada contendo espículas córneas; um osso peniano substituindo o corpo cavernoso e um saco suburetral ventral, com dois longos esporões córneos no seu interior, estão presentes no pênis desses espécimes. Na região escrotal não se observa limites externos nítidos do escroto. Dorsalmente, abaixo da lâmina interna do prepúcio, próximo ao óstio prepucial, verifica-se um par de glândulas prepuciais

Fissura placentária de gatas SRD, Felis catus - Linnaeus, 1758: aspectos macro e microscópicos

This research consists of study of shematic macroscopy cat's placenta and placental characterization as its type, zonary placenta, that 62,5% of cases presents a fissure at distal area of umbilical cord. This is formed by a joustfetal area, joustplacental area and middle area, histological findings: two arteries, a vein, two vitelline pedicule and two allantois pedicule. In the fissure, an allantoic epithelium covering this area at 10% of the cases and 90% found a trophoblast decrease compared with others placental areas out of the fissure. So, the feline placenta, in its maternal/fetal relationship shows a imcomplete zonary placenta, different of that occurs in other carnivores.Nossa pesquisa consiste no estudo esquemático macroscópico na placenta de gatos e a sua caracterização como tipo, placenta zonária, que 62,5% dos casos apresenta uma fissura na área distal do funículo umbilical. Esse é formado por uma área justa fetal, área justa placentária e área média, encontrando achados histológicos de 2 artérias, uma veia, 2 pedículos vitelínicos e 2 pedículos alantoidianos. Na fissura, encontramos um epitélio alantoidiano cobrindo esta área em 10% dos casos e, em 90% dos achados foram encontrados um trofoblasto diminuído comparado com outras áreas placentárias fora da fissura. Portanto, a placenta felina, com sua relação materno fetal mostra uma placenta zonária incompleta, diferente do ocorrido nos outros carnívoros

Effect of racial crossing on the seminal parameters of rams submitted to heat stress

The aim of this study was to evaluate the effect of racial crossing on seminal parameters of eight Santa Inês and crossbred (Santa Inês x Dorper) rams submitted to heat stress, and to monitor the return of these parameters to previously reported. Before to place the insulation bags, two collects of semen through electroejaculation were performed. The insulation pouches were made with double-layer plastic, internally lined with cotton, and fixed around the spermatic funiculus and scrotum with adhesive tape and bandage remaining on the testes of the animals for seven days. The first collect was performed on the day that the pouches were taken (day 0) and thereafter, every seven days, totalizing 15 measurements. Data were submitted to analysis of variance (ANOVA). The analyzed variables were subjected to Dunnett test at 5% probability to compare the values obtained before treatment with those obtained in the following days. In this study it was found that the animals restored normal seminal parameter after the insulation effects, however, the return rate differed slightly among the studied breeds. The crossbred animals restored the seminal patterns, on average, a week before Santa Inês. It is concluded that the racial crossing influences the semen parameters of rams submitted to heat stress. Keywords: motility, scrotal insulation, sperm concentration, sperm quality

Quantificação de células dos túbulos seminíferos e rendimento da espermatogênese em cutias (Dasyprocta aguti) criadas em cativeiros

This study has as objective to evaluate the spermatogenesis yield of Agoutis rised in captivity, through the rates found between cellular types of the seminiferous epithelium. The results showed that the spermatogenesis yield of the Agoutis since 9 to 14 months of age did not reach the stabilization point. The coefficient of efficiency of the spermatogonium mitoses, did not increase with the age. The meiotic yield, usual spermatogenesis yield and the Sertoli cells index didn't showed numeric variation at function of the age, however, it was not detected by statistic data.O presente estudo teve como objetivo avaliar o rendimento da espermatogênese de cutias criadas em cativeiro, por intermédio das razões encontradas entre tipos celulares do epitélio seminífero. Os resultados apontaram que o rendimento da espermatogênese da cutia dos nove aos quatorze meses de idade não chegou a um ponto de estabilização. O coeficiente de eficiência de mitoses espermatogoniais não aumentou com a idade. O rendimento meiótico, o rendimento geral da espermatogênese e o índice de células de Sertoli mostraram variações numéricas em função da idade, entretanto, não detectadas estatisticamente