RESUMO
The present study evaluated whether broiler femoral and tibiotarsal characteristics (as assessed at slaughter age) could be improved if birds were reared under their preferred temperature and whether continuous high or low incubation temperature during the fetal period improves bone characteristics of broilers reared under heat stress or thermal preference. Broiler breeder eggs were incubated from day 13 until hatching under cold (36 °C), control (37.5 °C), or hot (39 °C) temperatures. Under these conditions, the eggshell temperatures were 37.4 ± 0.1°C, 37.8 ± 0.15°C, and 38.8 ± 0.3°C, respectively. Then, broiler chicks were reared under control, preferred (determined previously in thermal preference test), or high temperatures. At day 42 of age, the broilers were weighed and euthanized, and femora and tibiotarsi collected to measure weight, length, diaphysis perimeter, breaking strength, maximum flexion, rigidity, ash, phosphorus, and calcium. Rearing under the preferred temperature did not affect broiler body weight or femoral and tibiotarsal characteristics (P > 0.05). In contrast, high rearing temperature, decreased the body weight, mineral contents of both bones, femoral breaking strength, and tibiotarsal rigidity (P < 0.05). Regarding incubation temperature effects, egg exposure to cold and hot temperatures during the fetal period minimized or avoided a few effects of high rearing temperature, such as those on femoral and tibiotarsal morphological characteristics, mineral composition, and mechanical properties at slaughter age (P < 0.05), but not all. In conclusion, rearing under the preferred broiler temperature did not improve the bone characteristics, and the negative effects of high rearing temperature on bone development were minimized but not completely prevented by high or low temperature incubation during the fetal period.
Assuntos
Criação de Animais Domésticos/normas , Embrião de Galinha/fisiologia , Galinhas/fisiologia , Abrigo para Animais/normas , Ossos da Perna/crescimento & desenvolvimento , Temperatura , Animais , Embrião de Galinha/embriologia , Ossos da Perna/embriologia , OsteogêneseRESUMO
The poultry industry is a sector of agribusiness which represents an important role in the country's 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.
Assuntos
Embrião de Galinha/embriologia , Desenvolvimento Embrionário , Endoderma/embriologia , Animais , Embrião de Galinha/anatomia & histologia , Embrião de Galinha/ultraestrutura , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Endoderma/anatomia & histologia , Endoderma/ultraestrutura , Fígado/anatomia & histologia , Fígado/embriologia , Fígado/ultraestrutura , Microscopia Eletrônica de Varredura , Baço/anatomia & histologia , Baço/embriologia , Baço/ultraestruturaRESUMO
The present study evaluated the effect of FSH treatment on ovarian cell proliferation in the hypophysectomized chicken embryo. Hypophysectomy (Hx) was performed by the partial decapitation technique. Two series of experiments were performed: (a) Hx embryos were treated at 8 days of development with recombinant human FSH (rhFSH) and evaluated at 9 days by measuring BrdU incorporation; (b) Hx embryos were injected with rhFSH and rhCG at 9 days of development and the proliferation rate was measured at 13 days. The presence of mRNA for FSHR and LHR in the ovary of control and Hx embryos was demonstrated by RT-PCR analysis. There was a decrease in the percentage of BrdU labeled cells in the absence of hypophysis at 9 and 13 days of incubation. The decrease was reversed with rhFSH treatment. This effect was observed in the ovarian surface epithelium and the somatic cells of the cortex and the medulla in the 9-day-old embryo. Moreover, the number of somatic, steroidogenic, and germ cells was reduced at 13 days of incubation in the Hx embryo; when treated with rhFSH the number of cells increased to the level of controls. In another experiment, ovaries of 9-day-old chicken embryos were organ cultured for 48 h in a serum-free medium with rhFSH and rhCG separately. The proliferation index was incremented by rhFSH compared to control and rhCG-treated embryos. Therefore, FSH stimulates somatic cell proliferation in the chicken embryo ovary as early as 9 days of development.
Assuntos
Embrião de Galinha/embriologia , Hormônio Foliculoestimulante/farmacologia , Hipofisectomia , Ovário/citologia , Ovário/embriologia , Animais , Antimetabólitos/farmacocinética , Bromodesoxiuridina/farmacocinética , Divisão Celular/efeitos dos fármacos , Galinhas , Meios de Cultura Livres de Soro/farmacologia , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Feminino , Técnicas de Cultura de Órgãos , Ovário/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptores do FSH/genética , Receptores do FSH/metabolismo , Receptores do LH/genética , Receptores do LH/metabolismo , Proteínas Recombinantes/farmacologiaRESUMO
The gonadal development of chicken embryo is regulated by hormones and growth factors. Transforming growth factor beta (TGF-beta) isoforms may play a critical role in the regulation of growth in chicken gonads. We have investigated the effect of the TGF-beta isoforms on the number of germ and somatic cells in the ovary of the chicken embryo. Ovaries were obtained from chicken embryos at 9 days of incubation. They were organ-cultured for 72 h in groups treated with TGF-beta1, TGF-beta2, soluble betaglycan, TGF-beta1 plus soluble betaglycan, or TGF-beta2 plus soluble betaglycan, and untreated (control). TGF-beta1 and TGF-beta2 diminished the somatic cell number in the ovary of the chicken embryo at this age by inhibiting the proliferation of the somatic cells without increasing apoptosis. On the other hand, TGF-beta1 and TGF-beta2 did not affect the number of germ cells in the cultured ovary. The capacity of TGF-beta1 and TGF-beta2 to diminish the number of somatic cells in the ovary was blocked with soluble betaglycan, a natural TGF-beta antagonist. However, changes in the location of germ cells within the ovary suggested that TGF-beta promoted the migration of the germ cells from the ovarian cortex to the medulla. Thus, TGF-beta affects germ and somatic cells in the ovary of the 9-day-old chicken embryo and inhibits the proliferation of somatic cells.
Assuntos
Embrião de Galinha/embriologia , Ovário/embriologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Contagem de Células , Divisão Celular , Embrião de Galinha/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Técnicas de Cultura de Órgãos , Ovário/citologia , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Proteoglicanas/metabolismo , Proteoglicanas/fisiologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Receptores de Fatores de Crescimento Transformadores beta/fisiologia , Proteínas Recombinantes/metabolismo , Fator de Crescimento Transformador beta/genéticaRESUMO
El presente trabajo estudia la toxicidad del AICI3 sobre la fibra periférica de ganglio espinal de embrión de pollo cultivado en gota pendiente. Una estructura del sistema nervioso, hasta el momento, escasamente valorada como un blanco para el Aluminio. Una solución stock de AICI3 750µM fue diluida en solución Tyrodes aplicada, de manera aguda, a los cultivos de 24 horas en una concentración final de 75µM. Los resultados fueron obtenidos siguiendo el esquema de la microscopia digital. La Microscopia Electrónica fue ejecutada de acuerdo a los pasos convencionales. Los resultados muestran una disminución del movimiento de la membrana ondulante, con retracción de la misma y formación de filopodios. Las células acompañantes no presentan signos de retracción. Se resalta la presencia de formaciones varicosas a lo largo de la fibra, mayor electrodensidad mitocondrial y vesículas axoplásmicas de mayor tamaño. Se desmuestra que el AICI3 altera estructura de la fibra periférica del ganglio espinal de mebrión de pollo en cultivo, comprometiendo el proceso de transporte axonal. Se involucra a las mitocondrias como organelos subcelulares claves en la toxicidad del AICI3. Habrá que realizar subsecuentes investigaciones orientadas a profundizar sobre la fijación de Aluminio a la estructura mitocondrial y el efecto neuro-tóxico del AICI3
Assuntos
Alumínio , Embrião de Galinha/embriologia , Fertilização in vitro , Mitocôndrias , Medicina , VenezuelaRESUMO
BACKGROUND: Fetal alcohol syndrome (FAS) is an embryopathology related to maternal alcohol drinking. The information concerning the factors involved in the prenatal mechanisms of ethanol action at the cellular and molecular levels is scarce. Because several abnormal changes in FAS involve regions colonized by cell lineages derived from neural crest cells (NCCs), it is reasonable to propose that epigenetic alteration of this cell population can represent an important component of the etiopathogeny. The aim of this work was to evaluate the direct effect of ethanol on a chick embryo model, as well as on in vitro NCC morphology and dynamic behavior. METHODS: After ethanol treatment, in ovo or cultured chick embryos were used to determine the anatomical development of and to quantify the migratory parameters and apoptosis of NCCs. Scanning electron microscopy was performed on ethanol-perfused (and control) cultures of cephalic and trunk NCCs; the actin cytoskeleton was evaluated, and morphometric and dynamic parameters were determined after time-lapse videorecording. Recovery capacity after ethanol treatment was also determined. RESULTS: Chick embryos submitted to conditions sufficient to induce FAS in mammals displayed developmental disruptions frequently accompanied by cephalic/facial anomalies. In vitro studies also indicated that cephalic and trunk NCCs exposed to ethanol exhibited significant and permanent changes regarding cell shape, surface morphology, apoptotic cell death, cytoskeleton, and distance and velocity traveled, as well as an abnormal pattern of migration. CONCLUSIONS: Taking into account that even a limited period of abnormal behavior may imply serious consequences in the final cues of an embryonic cell population, our results indicate that the biological effects of ethanol on early development-even during a short time-could induce permanent ontogenetic perturbations of NCCs, with potentially dramatic effects on embryonic morphogenesis. These results support an important participation of NCCs in the etiopathogeny of FAS.
Assuntos
Embrião de Galinha/citologia , Embrião de Galinha/efeitos dos fármacos , Etanol/farmacologia , Crista Neural/citologia , Crista Neural/efeitos dos fármacos , Animais , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Tamanho Celular/efeitos dos fármacos , Tamanho Celular/fisiologia , Células Cultivadas , Embrião de Galinha/embriologia , Embrião de Galinha/ultraestrutura , Microscopia Eletrônica de Varredura , Crista Neural/embriologia , Crista Neural/ultraestruturaRESUMO
Glutamate is the main neurotransmitter of photoreceptors, bipolar cells, and ganglion cells of the vertebrate retina. Three main classes of ionotropic glutamate receptors comprising different subunits can be distinguished: AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxasolepropionate), KA (kainate), and NMDA (N-methyl-D-aspartate). This study was undertaken to characterize the AMPA (GluR1, GluR2/3, and GluR4), KA (GluR5/6/7), and NMDA (NR1) ionotropic glutamate receptor subunits and to determine their distribution during the development of the chick retina by Western blotting and immunohistochemistry. Western blotting analysis at 1 day after hatching indicated that the antibodies against GluR1, 2/3, 4, and 5/6/7 and NR1 recognized specifically a single band of 100-110 kDa. In turn, immunohistochemistry at P1 showed that all subunits were expressed in cells of the inner nuclear and ganglion cell layers of the chick retina, mostly amacrine and ganglion cells, and their processes in the inner plexiform layer. In addition, stained processes in the outer plexiform layer were observed with the antibodies against GluR2/3, GluR4, and GluR5/6/7. Although all subunits appeared around E5-E6 in the prospective ganglion cell layer, and later in the prospective inner nuclear layer, the distribution of cells containing these glutamate receptor subunits revealed distinct ontogenetic patterns. This multiplicity of glutamate receptors may contribute to different processes that occur in the chick retina during development.
Assuntos
Embrião de Galinha/embriologia , Receptores de Glutamato/análise , Retina/química , Retina/embriologia , Animais , Especificidade de Anticorpos , Imuno-Histoquímica , Receptores de AMPA/análise , Receptores de AMPA/imunologia , Receptores de Glutamato/imunologia , Receptores de Ácido Caínico/análise , Receptores de Ácido Caínico/imunologia , Receptores de N-Metil-D-Aspartato/análise , Receptores de N-Metil-D-Aspartato/imunologiaRESUMO
A distribuição e sequência dos colágenos tipos I, II, III e IV, fibronectina, tenascina e proteoglicanas heparan sulfato e condroitin sulfato foram estudadas, em corpos vertebrais em desenvolvimento, ao nível dos membros superiore, de embriões de Gallus gallus domesticus L., durante o período de 2 a 21 dias (estádios 14-46) de incubação, e de animais pós-eclosão, utlizando-se o método imunohistoquímico com o anticorpo secundário biotinilado e o reagente peroxidase marcado com ExtrAvidina (método LAB), em espécimens fixados e incluídos em parafina ... As células notocordais e o epitélio do tubo neural induzem a migração das células mesenquimais, que sintetizam grande quantidade de colágenos tipos I e IV, fibronectina, tenascina e condroitin sulfato, durante os processos de migração e condrogênese inicial. A participação do colágeno tipo I, fibronectina e condroitin sulfato é essencial para as etapas de condro-apoptose e deposição da matriz óssea da osteogênese.
Assuntos
Embrião de Galinha , Galinhas , Matriz Extracelular , Embrião de Galinha/anatomia & histologia , Embrião de Galinha/crescimento & desenvolvimento , Embrião de Galinha/embriologia , Imuno-Histoquímica , Coluna Vertebral , Sulfatos de Condroitina , Colágeno Tipo I , Colágeno Tipo II , Colágeno Tipo III , Colágeno Tipo IV , Fibronectinas , Proteoglicanas de Heparan Sulfato , Mesoderma , TenascinaRESUMO
El citoesqueleto de la célula muscular es una compleja red de proteínas cuyo patrón de expresión está directamente relacionado con el proceso de diferenciación celular. La alfa-actinina, es una proteína que juega un papel decisivo en el proceso de contración de la célula muscular, es esencial para la estructuración de los sarcómeros ya que actúa como punto de anclaje o centro de organización de la preformación de filamentos de actina. La modificación de su expresión a lo largo de la madduración de la célula muscular tiene importantes implicaciones morfofuncionales para los miocardiocitos. Nuestros resultados, basados en el análisis mediante inmunofluorescencia de secciones criostáticas de corazón de pollo y miocardiocitos en cultivo de diferentes estadios del desarrollo, demuestran que en estadios tempranos (18 de Hamburger y Hamilton) la alfa-actinina se expresa débilmente, localizándose fundamentalmente en la membrana celular de los miocardiocitos y presentando un patrón de marcaja difuso en el citoplasma. Su expresión aumenta a lo largo del desarrollo cardíaco, produciéndose un aumento en la intensidad de marcaje, en el estadio 29 de Hamburger y Hamilton, que fue mayor en el miocardio ventricular que en el auricular lo que coincide con un cambio en el patrón de distrución de la alfa-actinina, que se estructura a lo largo de las miofibrillas de los miocardiocitos de este estadio. En estadios más avanzados (36 de Hamburger y Hamilton) se produce un incremento en la expresión de alfa-actinina pero sin cambios en su localización. El patrón de marcaje de la alfa- actinina durante el desarrollo cardíaco demuestra su utilidad como marcador del grado de diferenciación muscular y la importancia del estadio 29 HH en la maduración morfofuncional de la célula miocardiocítica, así como la diferente expresión en miocardios atrial y ventricular durante este proceso