Fatores associados à ocorrência da tuberculose bovina (TB), em dados de 209 fazendas, foram avaliados por meio de análise de variância. Os dados utilizados foram provenientes do levantamento epidemiológico por demanda, realizado nos rebanhos do estado do Rio de Janeiro, no período de 1959 até 1989. As variáveis significativas na análise bivariada foram incluídas no modelo e analisadas conjuntamente pelo método do modelo linear generalizado. A taxa de prevalência da TB nos rebanhos foi de 49,8%. As variáveis detectadas no estudo como as mais importantes para a ocorrência de TB foram: aleitamento (P=0,03) e as interações densidade x aleitamento (P=0,04) e produtividade x período (P=0,02). A importância da organização econômica da produção pecuária na ocorrência da TB pode ser evidenciada pelos resultados obtidos neste estudo. Este é um fator relevante em decorrência dos danos à saúde humana e animal.

The factors associated to the occurrence of bovine tuberculosis (TB) in 209 farms were evaluated by variance analysis. Data came were colleted in an epidemiological investigation from herds in the State of Rio de Janeiro, examined from 1959 to 1989. The significant variables were analyzed and submitted to generalized linear model. The prevalence rate of TB in herds was 49.8%. The most important variations detected in this study for occurrence of TB were: sucking (P=0.03) and interactions density vs. sucking system (P=0.04) and productivity vs. sucking period (P=0.02). The influence of the economical aspects of the farming systems on the occurrence of TB was confirmed by the results of this study. This is an important factor due to human and animal health hazards.

Associações espaço-temporais entre os fatores envolvidos na distribuição sazonal das larvas da mosca do berne - Dermatobia hominis (Linnaeus Jr., 1781) (Diptera: Cuterebridae) - em bovinos foram analisadas por geoprocessamento, utilizando-se o sistema de análise geoambiental da Universidade Federal do Rio de Janeiro, no município de Seropédica, RJ. Na primavera, 50% da área do município foi muito favorável ao desenvolvimento dessa miíase. Esse grau de favorabilidade reduziu-se para 35%, 23% e 12% no verão, outono e inverno, respectivamente.

Space-temporal associations between factors involved in the seasonal distribution of Dermatobia hominis (Linnaeus Jr., 1781) (Diptera: Cuterebridae) fly larvae in cattle were analyzed by geoprocessing using the geo-environment system of the Universidade Federal do Rio de Janeiro, in the municipality of Seropédica, RJ. In the spring, 50% of the area was favorable, reducing its extension to 35% in the summer, to 23% in the fall and to 12% in the winter.

Estudou-se a ocorrência sazonal de formas larvares e adultas de estrongilídeos nas mucosas do estômago, intestino delgado, ceco, colon ventral, colon dorsal e reto de 30 eqüídeos no Estado do Rio de Janeiro. Os grandes estrongilídeos foram encontrados em todas as mucosas e duas alíquotas de 5% do conteúdo foram retiradas para a procura de pequenos estrongilídeos. Artéria mesentérica, fígado, pâncreas e peritônio foram também examinados para larvas de estrongilídeos. As mucosas foram examinadas pela técnica de transiluminação. Larvas de Strongylus equinus (P<0,10) e adultos de Strongylus vulgaris (P<0,05) foram mais abundantes na estação seca. Larvas escistadas de ciatostomíneos o foram na estação chuvosa (P<0,02).

The seasonal abundance of lumenal and larval forms of equine strongyles in the State of Rio de Janeiro, Brazil was evaluated. Thirty horses referred to the Federal Rural University of Rio de Janeiro were necropsied and their gastrointestinal tracts were separated into stomach, small intestine, cecum, ventral colon, dorsal colon and rectum. Two aliquots of 5% of the content were collected and examined for the presence of small strongyles and the rest of the content was examined for the presence of large strongyles. The mesenteric artery, liver, pancreas and peritoneum were examined for the presence of strongyle larvae. The mucosa of intestine segments was cut into parts of equal length, and each one was examined by the mural transillumination technique. Higher abundances of larvae of Strongylus equinus (P<0.10) and of adults Strongylus vulgaris (P<0.05) were observed during the dry season. Encysted cyathostome larvae had the highest abundance during the rainy season (P<0.02).

Os modelos de simulação são ferramentas úteis na análise das inter-relações bioecológicas dos carrapatos. Partindo dessa premissa, objetivou-se avaliar o desempenho do programa BABSIM como auxiliar no estudo epidemiológico de B. microplus para o Estado de Minas Gerais, validando-se os ajustes no programa pela análise comparativa das curvas populacionais observadas e simuladas em Pedro Leopoldo e São Miguel do Anta, MG. As simulações foram realizadas com o programa BABSIM utilizando-se os parâmetros biológicos originais do programa e com ajustes nas temperaturas mínimas para oviposição e incubação dos ovos, no índice de encontro do hospedeiro pelas larvas, e no índice de sobrevivência dos estádios de vida livre. Os ajustes nos parâmetros biológicos propiciaram aumento na intensidade da carga parasitária, porém não foram suficientes para representar com maior precisão a dinâmica populacional no ecossistema em São Miguel do Anta. As simulações procedidas com os parâmetros biológicos originais e ajustados apresentaram comportamento variável para os diferentes anos em relação aos observados no estudo experimental de Pedro Leopoldo. Apesar de os resultados das simulações terem contribuído para a análise do conjunto de variáveis que interagem para determinar as variações do tamanho das populações de carrapatos nos ecossistemas estudados, eles indicaram, também, a necessidade de introduzir modificações nos submodelos que representam as inter-relações parasito-ambiente antrópico, assim como a necessidade de modificar o programa para permitir alterações de manejo dos animais, dentro de um mesmo ano de simulação, e, dessa maneira, justificar com maior precisão a dinâmica populacional em diferentes tipos de ecossistemas.

Simulation models are useful tools in the analysis of bio-ecological interrelations of ticks. The purpose of the present work was to evaluate the performance of the BABSIM program, in epidemiological studies on B. microplus in the State of Minas Gerais, Brazil. Adjustments were made in the program by comparative analysis of B. microplus population curves observed and simulated in Pedro Leopoldo and São Miguel do Anta, State of Minas Gerais. Two sets of simulation were carried out. One used the original parameters of BABSIM, whereas in the other adjustments were made to the minimum temperature threshold for preoviposition, incubation host-finding and survival rate factors of B. microplus. The adjustments to biological parameters were able to increase the simulated infestation levels of ticks, but unable to improve the prediction of population dynamic in the São Miguel do Anta ecosystem. The simulation results with adjustments and original parameters, showed variability through the years, in comparison to experimental field results of Pedro Leopoldo. Despite the contribution of the simulation results to the analysis of variables determining changes on ticks population size in the studied ecosystems, they showed that BABSIM needs new submodels that represent the interconnection between parasite and ecological conditions. Besides, there is a need to modify the program making possible changes in the animal management within the same year of simulation and, therefore, justifying the population dynamic in different ecosystems with higher accuracy.

In the present study we evaluated the binding of the radiopharmaceuticals sodium pertechnetate (Na 99mTcO4), methylenediphosphonic acid (99mTc-MDP) and glucoheptonate acid (99mTc-GHA) to blood elements using centrifugation and radioautographic techniques. Heparinized blood was incubated with the labelled compounds for 0, 1, 2, 3, 4, 6 and 24 h. Plasma (P) and blood cells (BC) were isolated and precipitated with 5% trichloroacetic acid (TCA), and soluble (SF) and insoluble fractions (IF) were separated. Blood samples were prepared (0 and 24 h) and coated with LM-1 radioautographic emulsions and percent radioactivity (%rad) in P and BC was determined. The binding of Na 99mTcO4 (%rad) to P was 61.2% (0 h) and 46.0% (24 h), and radioautography showed 63.7% (0 h) and 43.3% (24 h). The binding to BC was 38.8% (0 h) and 54.0% (24 h), and radioautography showed 36.3% (0 h) and 56.7% (24 h). 99mTc-MDP study presented 91.1% (0 h) to P and 87.2% (24 h), and radioautography showed 67.9% (0 h) and 67.4% (24 h). The binding to BC was 8.9% (0 h) and 12.8% (24 h), and radioautography showed 32.1% (0 h) and 32.6% (24 h). 99mTc-GHA study was 90.1% (0 h) to P and 79.9% (24 h), and radioautography showed 67.2% (0 h) and 60.1% (24 h). The binding to BC was 9.9% (0 h) and 20.1% (24 h), and radioautography showed 32.8% (0 h) and 39.9% (24 h). The comparison of the obtained results suggests that the binding to plasma and blood cells in the two techniques used (radioautography and centrifugation) is qualitatively in accordance

Previous studies have shown that in vitro thyroid peroxidase (TPO) iodide oxidation activity is decreased and thyroid T4-5'-deiodinase activity is increased 15 days after induction of experimental diabetes mellitus (DM). In the present study we used thyroid histoautoradiography, an indirect assay of in vivo TPO activity, to determine the possible parallelism between the in vitro and in vivo changes induced by experimental DM. DM was induced in male Wistar rats (about 250 g body weight) by a single ip streptozotocin injection (45 mg/kg), while control (C) animals received a single injection of the vehicle. Seven and 30 days after diabetes induction, each diabetic and control animal was given ip a tracer dose of 125I (2 µCi), 2.5 h before thyroid excision. The glands were counted, weighed, fixed in Bouin's solution, embedded in paraffin and cut. The sections were stained with HE and exposed to NTB-2 emulsion (Kodak). The autohistograms were developed and the quantitative distribution of silver grains was evaluated with a computerized image analyzer system. Thyroid radioiodine uptake was significantly decreased only after 30 days of DM (C: 0.38 ± 0.05 vs DM: 0.20 ± 0.04%/mg thyroid, P<0.05) while in vivo TPO activity was significantly decreased 7 and 30 days after DM induction (C: 5.3 and 4.5 grains/100 µm2 vs DM: 2.9 and 1.6 grains/100 µm2, respectively, P<0.05 ). These data suggest that insulin deficiency first reduces in vivo TPO activity during short-term experimental diabetes mellitus