Desenvolvimento morfolôgico dos ovários em embriões e fetos bovinos da raça Nelore

The morphologic events related to the prenatal development of the ovaries in 81 Nelore breed embryos and fetuses gathered in a local slaughterhouse, with age range from 26 to 240 days following fecundation were studied. The age of fetuses was estimated from measures taken in the cranium-caudal direction. The sex was identified from macroscopic observations and using Polymerase Chain Reaction (PCR) technique. For histology the gonads were fixed in Bourn's fluid for 24 hours and 5 μm thick section's were stained with hematoxylin-eosin. Formation of gonadal ridge and presence of germinal cells were found within it at 29 and 34 days, respectively. Oogonia and primordial follicles, unlike the growing follicles, exhibited significant differences in diameter in the various periods studied. Positive correlation (P<0.05) was found between the diameter of oogonia and their nucleus as well as between primordial and growing follicles with their oocytes and respective nuclei. The gonad was fully formed at 40 days. Primordial follicles, in the growing stage, and antral follicles first appeared, approximately at 95, 140, and 180 days, respectively. Despite the onset and duration of oogenesis being similar to that of taurine breeds, folliculogenesis initiates at an early stages in the Nelore breed.

Determination of acetonitrile and cyanide in rat blood: Application to an experimental study

Methods were developed for the analysis of acetonitrile and its metabolite cyanide in the blood of rats exposed to acetonitrile. Acetonitrile was analyzed by the headspace technique coupled to gas chromatography with detection by flame ionization, and cyanide was analyzed by high-performance liquid chromatography with fluorescence detection (λ ex = 418 nm and λ em = 460 nm) after derivatization of the ion with naphthalene 2,3-dicarboxyaldehyde and taurine. The quantitation limits of the methods for the analysis of acetonitrile and cyanide were 4.875 μg/mL and 0.025 μg/mL, respectively. The coefficients of variation of 10% or less obtained for intra- and interassay precision indicate the precision of these analytical methods and the systematic errors, all less than 5%, indicate that the methods are quite accurate. The methods were applied to an experimental study after the animals received acetonitrile at the doses of 2 mmol/kg or 5 mmol/kg.

Does cotinine act upon reactive oxygen species and peroxidases?

Nicotine, an oxidizing agent, is certainly one of the most widely used alkaloids in the world. It is, together with its main metabolite, cotinine, responsible for tobacco-dependence. The use of tobacco is closely associated with lung disease, morphological leukocyte modification and generation of oxidant species. The aim of this study was to look for a possible relationship between cotinine, oxidant species generation and oxidative processes. After studying the action of cotinine in some chemical oxidation models and on the enzymatic kinetics of peroxidases (myeloperoxidase and horseradish peroxidase), we concluded that cotinine does not act directly upon H 2O 2, HOCl, taurine chloramines, horseradish peroxidase or myeloperoxidase.

Immunophenotyping of thymic lymphoma in a Nelore cow

Thymic lymphoma is a malignant lymphoid neoplasm that affects several species, including cattle. This type of neoplasia can lead to death due to malignant cell infiltration in different organs. The classification of this neoplasm may predict prognosis and response to treatment. Immunophenotyping is one of the ways to perform this classification. There are reports about the performance of immunohistochemistry (IHC) to classify thymic lymphoma only in taurine cattle, therefore the aim of this report is to describe the immunophenotype of a thymic lymphoma in a Nelore cow. Immunostaining was performed with monoclonal antibodies (CD79, CD4 and CD8). The tumor cells showed positive staining only for CD8 T lymphocytes, coinciding with the disease progression, since the T lymphoma type is more aggressive.

Cardiac remodeling induced by smoking: Concepts, relevance, and potential mechanisms

Cardiac or ventricular remodeling is characterized by molecular, cellular, and interstitial alterations that lead to changes in heart size, mass, geometry and function in response to a given insult. Currently, tobacco smoke exposure is recognized as one of these insults. Indeed, tobacco smoke exposure induces the enlargement of the left-sided cardiac chambers, myocardial hypertrophy, and ventricular dysfunction. Potential mechanisms for these alterations include hemodynamic and neurohormonal changes, oxidative stress, inflammation, nitric oxide bioavailability, matrix metalloproteinases and mitogen-activated protein kinase activation. This review will focus on the concepts, relevance, and potential mechanisms of cardiac remodeling induced by tobacco smoke. © 2012 Bentham Science Publishers.

Influence of the physiological state on infestation by Rhipicephalus microplus in dairy cows

The purpose of this study was to identify the influence of physiological state, season, breed, number of lactations, dairy productivity, and stocking rate on infestation by Rhipicephalus microplus in dairy cows. Two hundred cows were selected through proportional representative sampling at the Seropédica Experimental Station (Pesagro-Rio), Brazil. Fully or partially engorged R. microplus females measuring between 4.5 and 8.0. mm were counted on the right side of each animal. The tick infestation prevalence data were analyzed in relation to the risk factors, using multiple logistic regression. Associations between prevalence and its possible influencing determinants were measured using odds ratios. The average tick count of cows during the peripartum and lactation periods was significantly higher (p<0.05; OR=4.82) than the count in dry cows. Taurine animals showed significantly higher infestation (p<0.05; OR=3.28) than pure zebuine animals. Among cross-bred animals, the infestation was higher (p<0.05) in F1 animals (1/2 taurine × 1/2 zebuine) than in Girolando animals (5/8 zebuine × 3/8 taurine). Primiparous cows (p<0.05) had significantly heavier infestations than multiparous cows. Dairy production showed a positive correlation with tick infestation (p<0.03; OR=2.94), such that the most productive animals were the most parasitized ones. Animals kept at high densities were significantly more heavily infested (p<0.05, OR=6.32) than animals kept at low density. First-lactation and high-productivity taurine animals were more vulnerable to R. microplus, thus comprising a high-risk group in dairy herds. © 2012 Elsevier GmbH.

Detecting Loci under Recent Positive Selection in Dairy and Beef Cattle by Combining Different Genome-Wide Scan Methods

As the methodologies available for the detection of positive selection from genomic data vary in terms of assumptions and execution, weak correlations are expected among them. However, if there is any given signal that is consistently supported across different methodologies, it is strong evidence that the locus has been under past selection. In this paper, a straightforward frequentist approach based on the Stouffer Method to combine P-values across different tests for evidence of recent positive selection in common variations, as well as strategies for extracting biological information from the detected signals, were described and applied to high density single nucleotide polymorphism (SNP) data generated from dairy and beef cattle (taurine and indicine). The ancestral Bovinae allele state of over 440,000 SNP is also reported. Using this combination of methods, highly significant (P<3.17×10-7) population-specific sweeps pointing out to candidate genes and pathways that may be involved in beef and dairy production were identified. The most significant signal was found in the Cornichon homolog 3 gene (CNIH3) in Brown Swiss (P = 3.82×10-12), and may be involved in the regulation of pre-ovulatory luteinizing hormone surge. Other putative pathways under selection are the glucolysis/gluconeogenesis, transcription machinery and chemokine/cytokine activity in Angus; calpain-calpastatin system and ribosome biogenesis in Brown Swiss; and gangliosides deposition in milk fat globules in Gyr. The composite method, combined with the strategies applied to retrieve functional information, may be a useful tool for surveying genome-wide selective sweeps and providing insights in to the source of selection.

Proteômica para investigar a congelabilidade do semen bovino

The present study was undertaken the protein composition in 2D-electrophoretic pattern (2DE) of the seminal plasma (SP) can interfere in the semen bull freezability, and if we can use that for predicting semen bull freezability. Samples were obtained of 20 bulls (different breeds) with a minimum of 3 years history semen production in commercial semen collection Center. All animals ranged between 2 - 7 years of age. The semen freezability was calculated by # of thawed and approved ejaculates / # of ejaculates submitted to cryopreservation (after semen evaluation and approved to submitted to freeze). The bulls were divided in 3 groups: HIGH (=>80% ejaculates approved); MEDIUM (>60% and <79% ejaculates approved); LOW (=<59% ejaculates approved); the pattern and criteria were the same used in the routine of the commercial semen Center. 68 gels were carried through by 2DE of SP samples indicated 225 detected spots with protein different amount (VION) comparing. Comparing bull ́s semen freezability and VION of each spot found difference among 2 spots from High and Low, even considering just spots with % of detection frequency bigger than 75%. The taurine bulls demonstrated more homogeneous profile when comparing with zebu bulls, considering number and frequency of appearance of spots. The results showed that proteomics can be a useful tool to predict the semen freezability, but we ́ll need to study better the interactions between sperm membrane, seminal plasma and extender to comprehend better which proteome phenotype interfere positive or negatively in the semen freezability.

Genome-wide association study for birth weight in Nellore cattle points to previously described orthologous genes affecting human and bovine height

Background: Birth weight (BW) is an economically important trait in beef cattle, and is associated with growth- and stature-related traits and calving difficulty. One region of the cattle genome, located on Bos primigenius taurus chromosome 14 (BTA14), has been previously shown to be associated with stature by multiple independent studies, and contains orthologous genes affecting human height. A genome-wide association study (GWAS) for BW in Brazilian Nellore cattle (Bos primigenius indicus) was performed using estimated breeding values (EBVs) of 654 progeny-tested bulls genotyped for over 777,000 single nucleotide polymorphisms (SNPs).Results: The most significant SNP (rs133012258, PGC = 1.34 × 10-9), located at BTA14:25376827, explained 4.62% of the variance in BW EBVs. The surrounding 1 Mb region presented high identity with human, pig and mouse autosomes 8, 4 and 4, respectively, and contains the orthologous height genes PLAG1, CHCHD7, MOS, RPS20, LYN, RDHE2 (SDR16C5) and PENK. The region also overlapped 28 quantitative trait loci (QTLs) previously reported in literature by linkage mapping studies in cattle, including QTLs for birth weight, mature height, carcass weight, stature, pre-weaning average daily gain, calving ease, and gestation length.Conclusions: This study presents the first GWAS applying a high-density SNP panel to identify putative chromosome regions affecting birth weight in Nellore cattle. These results suggest that the QTLs on BTA14 associated with body size in taurine cattle (Bos primigenius taurus) also affect birth weight and size in zebu cattle (Bos primigenius indicus). © 2013 Utsunomiya et al.; licensee BioMed Central Ltd.

Estado nutricional e níveis plasmáticos de trauma e seus precursores em pacientes portadores de neoplasias malignas de esôfago

Pós-graduação em Bases Gerais da Cirurgia - FMB

Efeito da suplementação de taurina na oxidação de substratos energéticos e no desempenho de atletas nadadores

Pós-graduação em Alimentos e Nutrição - FCFAR

Caracterização do perfil da ação do ácido gálico e seus derivados sobre processos oxidativos in vitro e ex vivo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Produção de quimeras embrionárias bovinas mediante a agregação de embriões diploides (Bos indicus) e tetraploides (Bos indicus)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influência da taurina na remodelação cardíaca induzida pela exposição à fumaça do cigarro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da deficiência de taurina no coração

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)