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1.
Anat Histol Embryol ; 50(6): 947-955, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34549460

RESUMO

To determine the presence, quantity and distribution of androgen (AR) and oestrogen receptors (ER) in the antler velvet (AV), samples were collected from adult and yearling pampas deer males, as well as skin from the ventrolateral abdominal area (ASK). Samples were analysed with ligand-binding assays for AR and ER activity and processed for AR and ERß immunohistochemistry. There was more content of AR in adults than in yearling males (p = 0.02), as well as a category and type of tissue interaction (p = 0.03). There was more ER content in adults than in yearling males (p = 0.005) and in the AV than in the skin (p = 0.0001). The AR-positive score (PS) was greater in AV than in ASK in the surface stroma (p = 0.0007). In the intermediate epidermis, the AR PS was greater in adults than in yearling males (p = 0.04) and in the ASK than in the AV (p < 0.0001). There was a male category and type of tissue interaction for AR PS in the sebaceous glands (p = 0.014). The ERß PS in the surface stroma was greater in ASK than in AV (p = 0.004) and tended to be greater in yearling than in adult males (p = 0.093). The ERß PS in the intermediate epithelium and the sebaceous glands was greater in adults than in yearlings (p = 0.004 and p = 0.007, respectively). In conclusion, we reported for the first time the presence of AR and ER in the velvet skin of growing antlers in pampas deer males. Therefore, the velvet skin is sensitive to both androgens and oestrogens. Furthermore, the greater content of oestrogen receptors in the velvet of adult males suggests that adults are more sensitive to this hormone than yearlings, and thus, oestrogens have greater importance in velvet activity regulation in adult males.


Assuntos
Chifres de Veado , Cervos , Androgênios , Animais , Masculino , Receptores de Estrogênio , Pele
2.
Anim Reprod ; 17(2): e20200021, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32714462

RESUMO

The pampas deer is an endangered species, from which reproductive biology little is known. We aimed to describe and compare the reproductive seasonal patterns of adult and yearling pampas deer stags throughout the year, including morphological traits, testosterone concentration, sperm morphology and cryoresistance pattern changes. Six adult (AS) and five yearling (YS) stags were captured with anesthetic darts once in winter, spring, summer and autumn to study morphological variables, serum testosterone and semen. Adult males were heavier, their neck girth tended to be greater and their testosterone concentration was higher than in YS. Animals were heavier in summer and autumn. Neck girth and testosterone concentration were greater in autumn. Scrotal circumference, testicular volume and gonado-somatic index varied with seasons, decreasing from winter to spring, increasing in summer and remaining in greater values in autumn. Sperm quality had maximum values from summer to winter. However, the cryoresistance ratio of motility score was greater in spring. In conclusion, in the captivity conditions, pampas deer stags seems to present a light seasonal reproductive pattern, with maximum testis size, testosterone secretion and fresh semen quality in autumn. Nevertheless, sperm cryoresistance ratio seemed to remain stable along the year. Although YS were still growing, they achieved similar semen quality than AS.

3.
PLoS One ; 15(1): e0227946, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978160

RESUMO

Sperm cryopreservation by ultra-rapid cooling based on dropping small volumes of sperm suspension directly into liquid nitrogen, has been successful in some wild ruminant species, including the Iberian ibex (Capra pyrenaica). In ultra-rapid cooling, the contents of these droplets are expected to enter a stable, glass-like state, but to the best of our knowledge no information exists regarding the presence or absence of ice formation in the extracellular milieu when using this technique. Different modifications to the extracellular milieu likely inflict different types of damage on the plasmalemma, the acrosome and mitochondrial membranes. The aims of the present work were: 1) to examine the physical state of the extracellular milieu after cryopreservation at slow and ultra-rapid cooling rates-and thus determine whether ultra-rapid cooling vitrifies the extracellular milieu; and 2) to compare, using conventional sperm analysis techniques and scanning and transmission electron microscopy, the damage to sperm caused by these two methods. Sperm samples were obtained by the transrectal ultrasound-guided massage method (TUMASG) from anesthetized Iberian ibexes, and cryopreserved using slow and ultra-rapid cooling techniques. Sperm motility (22.95 ± 3.22% vs 4.42 ± 0.86%), viability (25.64 ± 3.71% vs 12.8 ± 2.50%), acrosome integrity (41.45± 3.73% vs 27.00 ± 1.84%) and mitochondrial membrane integrity (16.52 ± 3.75% vs 4.00 ± 0.65%) were better after slow cooling (P<0.001) than after ultra-rapid technique. Cryo-scanning electron microscopy (Cryo-SEM) suggested that the vitrified state was not achieved by ultra-rapid cooling, and that the ice crystals formed were smaller and had more stretchmarks (P<0.001) than after slow cooling. Scanning electron microscopy revealed no differences in the types of damage caused by the examined techniques, although transmission electron microscopy showed the damage to the plasmalemma and mitochondrial membrane to be worse after ultra-rapid cooling. In conclusion ultra-rapid cooling provoked more membrane damage than slow cooling, perhaps due to the extracellular ice crystals formed.


Assuntos
Cabras/genética , Análise do Sêmen/métodos , Preservação do Sêmen/métodos , Espermatozoides/fisiologia , Acrossomo/efeitos dos fármacos , Acrossomo/ultraestrutura , Animais , Temperatura Baixa , Criopreservação , Crioprotetores/farmacologia , Humanos , Masculino , Motilidade dos Espermatozoides/efeitos dos fármacos , Vitrificação/efeitos dos fármacos
4.
Anat Histol Embryol ; 48(4): 306-314, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30907032

RESUMO

The tortuous nature of the ovine cervix restricts the transcervical passage of the cannula, and many studies have aimed to understand the endocrine mechanism of the remodelling of cervical tissue in adult ewe. However, little is known about the remodelling of the cervical tissue during the prepubertal development of the lambs. To obtain histochemical and biochemical evidence about the nature of the prepubertal development of the cervix of the ewe, cervices of Corriedale lambs obtained at 0, 1, 2, 4, 6 and 8 months of age (n = 5 to 6 in each) were processed. Neutral and acidic glycosaminoglycans (by PAS-Alcian stain) were weakly in the cervical stroma and not shown change during the development, whereas the percentage volume of fibrillar collagen (by van Gieson stain) increases throughout the experimental period in the superficial fold stroma and deep wall stroma (p < 0.05). The relative cervical weight (g/kg of body weight) and the collagen concentration (by spectrophotometry, mg/mg wet tissue) showed an early decreasing phase from months 0 to 4 and a later increasing phase from months 4 to 8 (p < 0.05). The latent form of matrix metalloproteinase-2 (MMP-2) detected by gelatin zymography (ng/mg protein) decreased from months 0 to 2 and increased from months 4 to 8, whereas the activated form decreased from months 0 to 2, remained low until month 6 and then recovered on month 8 (p < 0.0001). Data suggest that the relative cervical weight biphasic pattern during the development is related to MMP-2-dependent changes in the collagen content.


Assuntos
Colo do Útero/química , Colágeno/análise , Glicosaminoglicanos/análise , Metaloproteinase 2 da Matriz/análise , Metaloproteinase 9 da Matriz/análise , Ovinos/crescimento & desenvolvimento , Animais , Peso Corporal , Colo do Útero/enzimologia , Colo do Útero/crescimento & desenvolvimento , Feminino , Histocitoquímica/veterinária , Tamanho do Órgão , Inclusão em Parafina/veterinária , Espectrofotometria/veterinária , Coloração e Rotulagem/veterinária
5.
Reprod Domest Anim ; 54(3): 506-513, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30499612

RESUMO

In order to study the effect of undernutrition during gestation on the testicular development in rats and its impact on mitosis, apoptosis and the relative abundance of androgen receptor expression, twenty primiparous 3-month-old Sprague-Dawley (Rattus norvegicus) rats, weighing 246 ± 4.0 grams when the experiment began, were mated by the same male. Control group (CG), n = 10, fed ad libitum with water and rat chow and restricted group (RG, n = 10) fed throughout pregnancy and until birth with 40% of the ad libitum maternal daily feed intake. Litters from both groups suckled for 25 days, RG with 14 pups/litter and CG with 8 pups/litter. After weaning, all animals had access to ad libitum food and water. Testicular samples were taken from male pups at 2, 25 and 100 days of age. Immunohistochemistry was used to evidence androgen receptor (AR) expression in apoptotic (caspase 3-positive) and proliferating (PCNA-positive) cells. Three hundred nuclei of sustentacular (or Sertoli: SC), interstitial (or Leydig: LC), myoid (MC) cells as well as gonocytes (GC) were evaluated. Neither LC nor GC showed any differences between groups. However, SC androgen receptor (AR) positivity index in neonatal animals was lower in RG (1.27 ± 0.22 vs. 1.65 ± 0.17**). MC showed lower AR positivity index at 2 (2.69 ± 0.046 vs. 2.8 ± 0.055**) and 25 (1.34 ± 0.097 vs. 1.56 ± 0.1***) days of life; at 100 days of life, there was a greater number of apoptotic MC in the RG (8.5 ± 0.4 vs. 2.95 ± 1.1***). Thus, the present experiment demonstrates that the population dynamics of MC are affected by foetal programming due to undernutrition.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Apoptose , Desnutrição , Mitose , Receptores Androgênicos/metabolismo , Testículo/fisiologia , Animais , Animais Recém-Nascidos , Feminino , Imuno-Histoquímica , Lactação , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Reprodução , Testículo/patologia
6.
Int. j. morphol ; 36(3): 895-900, Sept. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-954204

RESUMO

La reserpina es un antipsicótico e hipotensor arterial que reduce significativamente los niveles de monoaminas centrales, y también es utilizada para modelar los cuadros depresivos humanos en animales de laboratorio. Este trabajo estudió, en ratas Wistar machos adolescentes, cómo la reserpina afecta indicadores moleculares de la función testicular, la cual se ha visto alterada en humanos deprimidos. Una semana luego de finalizado el tratamiento con reserpina (4 dosis de 0,0 o 1,0 mg/Kg, cada 2 días) la respuesta ansiosa y depresiva fue evaluada en un laberinto en cruz elevado. Posteriormente, se sacrificaron los animales y disecaron los testículos, los cuales fueron fijados e incluidos en bloques de parafina de donde se obtuvieron cortes histológicos de 6 µm de espesor. Estos se utilizaron para medir el diámetro de los túbulos seminíferos y para medir por inmunohistoquímica el porcentaje de células intersticiales (células de Leydig) positivas a (1) Factor neurotrófico derivado del cerebro, (2) antígeno nuclear de células en proliferación (BDNF y PCNA, respectivamente, por sus siglas en inglés), y a (3) caspasa-3. Se obtuvo también un índice de positividad al receptor de andrógenos en las células intersticiales. La expresión del receptor de andrógeno fue evaluada utilizando una escala semicuantitativa de escores (0, 1, 2 y 3) y el resto de las moléculas por presencia o ausencia de expresión de cada antígeno investigado en 300 células por preparado. Los resultados comportamentales indicaron alteraciones en la respuesta de ansiedad y una significativa depresión motora (e.g., mayor latencia en conductas de escape del sector blanco) en los animales tratados con reserpina. No se observaron diferencias en los diámetros de los túbulos seminíferos ni en la expresión del receptor de andrógeno, mientras que sí se encontró mayor proporción de células intersticiales positivas a BDNF y PCNA, y menor proporción de células positivas a caspasa-3, en los animales tratados. Los resultados corroboran la capacidad de la reserpina para reproducir rasgos comportamentales de la depresión. La administración de la droga, sin embargo, no parece reproducir a nivel testicular los efectos deletéreos encontrados en humanos deprimidos, e incluso los resultados sugieren que la reserpina puede mejorar algunos aspectos de la funcionalidad testicular relacionadas con la actividad de las células intersticiales en ratas.


Reserpine, a drug that depletes central monoamines, has been used as an antipsychotic and arterial hypotensive, and to model depression in animals. The present study analyzed, in adolescent male rats, the effects of chronic reserpine treatment on molecular indexes of testicular function. A week after termination of the treatment (4 doses of 0,0 or 1,0 mg/Kg/every 48 h) the animals were tested for anxiety response and depression patterns in an elevated plus maze. They were then euthanized, their testes dissected, fixed and embedded in paraffin to obtain blocks. Histological sections (6 µm) were obtained and used to measure the diameter of seminiferous tubules and the expression in Leydig cells of Brain-derived neurotrophic factor (BDNF), Proliferating cell nuclear antigen (PCNA), Caspase-3 and androgen receptors, by immunohistochemistry. Behavioral results indicated significant alterations in anxiety responses and a significant motor depression (e.g., greater latency to escape from the white sector). There were no differences between groups in the diameter of seminiferous tubules nor in the androgen receptors positivity. Reserpine-treated animals, however, exhibited more BDNF and PCNA positive cells, and less positive Caspase-3 cells in Leydig cells, than control animals. The results corroborate the efficacy of reserpine to reproduce some of the behavioral components of depression. The drug, however, does not seem to exert in rats the same effects on testicular function that have been found in humans diagnosed with depression. Furthermore the drug seems to enhance some aspects of testicular function related to Leydig cells function in rats.


Assuntos
Animais , Masculino , Ratos , Reserpina/farmacologia , Testículo/efeitos dos fármacos , Antipsicóticos/farmacologia , Antígeno Nuclear de Célula em Proliferação/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/efeitos dos fármacos , Células Intersticiais do Testículo/efeitos dos fármacos , Testículo/citologia , Imuno-Histoquímica , Ratos Wistar , Caspase 3/efeitos dos fármacos
7.
PLoS One ; 13(7): e0200732, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30040835

RESUMO

Transcriptome deep sequencing is a powerful tool for exploring the genetic architecture of complex traits. Gene expression patterns may explain a high degree of the observed phenotypic differences in histochemical and metabolic parameters related to meat quality among different muscles. In this study, we sequenced by RNA-Seq the whole transcriptome of nine lamb muscles: Semimembranosus (SM), Semitendinosus (ST), Cranial gluteobiceps, Gluteus medius (GM), Rectus femoris, Supraspinatus (SS), Longissimus lumborum (LL), Adductor and Psoas major. Significant gene expression differences were detected between almost all pairwise comparisons, being more pronounced between SS and ST, SM and LL, and ST and GM. These differences can be explained in terms of ATPase and glycolytic activities, muscle fiber typing and oxidative score, clustering muscles as fast glycolytic, intermediate or slow oxidative. ST showed up-regulation of gene pathways related to carbohydrate metabolism, energy generation and protein turnover as expected from a fast white muscle. SS showed myosin isoforms typical of slow muscles and high expression of genes related to calcium homeostasis and vascularization. SM, LL and GM showed in general intermediate gene expression patterns. Several novel transcripts were detected, mostly related to muscle contraction and structure, oxidative metabolism, lipid metabolism and protein phosphorylation. Expression profiles were consistent with previous histochemical and metabolic characterization of these muscles. Up-regulation of ion transport genes may account for significant differences in water holding capacity. High expression of genes related to cell adhesion, cytoskeleton organization, extracellular matrix components and protein phosphorylation may be related to meat yellowness and lower tenderness scores. Differential expression of genes related to glycolytic activity and lactic acid generation among fast, intermediate and slow muscles may explain the detected final meat pH differences. These results reveal new candidate genes associated with lamb meat quality, and give a deeper insight into the genetic architecture of these complex traits.


Assuntos
Qualidade dos Alimentos , Perfilação da Expressão Gênica/veterinária , Carne , Músculo Esquelético/metabolismo , Carneiro Doméstico/genética , Animais , Glicólise/genética , Ácido Láctico/biossíntese , RNA/genética , Análise de Sequência de RNA/veterinária , Carneiro Doméstico/metabolismo
8.
Vet Parasitol ; 229: 50-53, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-27809978

RESUMO

Reproductive alterations in hosts infected by parasites have been recognized in several phyla, especially in arthropods and mollusks, but it has been less studied in higher vertebrates, particularly in mammals. In the present study, ten eight week-old female New Zealand rabbits (Oryctolagus cuniculus) were either infected with Taenia pisiformis eggs or uninfected, and 7 weeks later they were mated. We found that serum progesterone levels were increased during pregnancy in infected does. At birth, litter size of infected does was reduced by half as compared to the control group, and, at weaning, the number of kits and the weight of litters was lower. Since serum progesterone levels have a key role in the maintenance of pregnancy and implantation, we propose that the observed prolificacy alterations in does infected with T. pisiformis infection were due to changes in the levels of circulating progesterone during pregnancy.


Assuntos
Cisticercose/veterinária , Progesterona/sangue , Coelhos , Taenia/isolamento & purificação , Animais , Estudos de Casos e Controles , Cisticercose/patologia , Feminino , Tamanho da Ninhada de Vivíparos , Gravidez
9.
Infect Immun ; 82(4): 1465-76, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24421045

RESUMO

The nontyphoidal Salmonella enterica serovar Dublin is adapted to cattle but infrequently infects humans, very often resulting in invasive infections with high levels of morbidity and mortality. A Salmonella-induced intestinal acute inflammatory response is postulated as a mechanism to prevent bacterial dissemination to systemic sites. In S. enterica serovar Typhimurium, flagella contribute to this response by providing motility and FliC-mediated activation of pattern recognition receptors. In this study, we found 4 Salmonella enterica isolates, with the antigenic formula 9,12:-:-, that, based on fliC sequence and multilocus sequence type (MLST) analyses, are aflagellate S. Dublin isolates. Interestingly, all were obtained from human bloodstream infections. Thus, we investigated the potential role of flagella in the unusual invasiveness exhibited by S. Dublin in humans by analyzing flagellation and proinflammatory properties of a collection of 10 S. Dublin human clinical isolates. We found that 4 of 7 blood isolates were aflagellate due to significantly reduced levels of fliC expression, whereas all 3 isolates from other sources were flagellated. Lack of flagella correlated with a reduced ability of triggering interleukin-8 (IL-8) and CCL20 chemokine expression in human intestinal Caco-2 cells and with reduced early inflammation in the ceca of streptomycin-pretreated C57/BL6 mice. These results indicate that flagella contribute to the host intestinal inflammatory response to Salmonella serovar Dublin and suggest that their absence may contribute to its systemic dissemination through dampening of the gut immune response. Analysis of FliC production in a collection of cattle isolates indicated that the aflagellate phenotype is widely distributed in field isolates of S. Dublin.


Assuntos
Flagelos/fisiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/patogenicidade , Análise de Variância , Animais , Células CACO-2 , Ceco , Quimiocina CCL20/metabolismo , Feminino , Flagelina/genética , Flagelina/metabolismo , Humanos , Interleucina-8/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas , Infecções por Salmonella/patologia , Salmonella enterica/fisiologia , Especificidade da Espécie
10.
Acta Vet Scand ; 50: 16, 2008 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-18534014

RESUMO

The pampas deer (Ozotoceros bezoarticus) is a South American grazing deer which is in extreme danger of extinction. Very little is known about the biology of the pampas deer. Moreover, most information has not been published in peer-reviewed scientific journals, and is only available in local publications, theses, etc. Therefore, our aim was to update and summarize the available information regarding the reproductive biology of the pampas deer. Moreover, in most sections, we have also included new, unpublished information. Detailed descriptions are provided of the anatomy of both the female and the male reproductive tract, puberty onset, the oestrous cycle and gestational length. Birthing and the early postpartum period are described, as are maternal behaviour and early fawn development, seasonal distribution of births, seasonal changes in male reproduction and antler cycle, reproductive behaviour, semen collection, and cryopreservation. Finally, an overview is given and future directions of research are proposed.


Assuntos
Cervos/fisiologia , Reprodução/fisiologia , Animais , Cervos/anatomia & histologia , Feminino , Genitália Feminina/anatomia & histologia , Genitália Masculina/anatomia & histologia , Masculino , Técnicas de Reprodução Assistida/veterinária , Comportamento Sexual Animal/fisiologia
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