L. A. Pellegrin

Leptospirosis serosurvey in bovines from Brazilian Pantanal using IGG ELISA with recombinant protein LipL32 and microscopic agglutination test

This investigation was carried out in Brazilian Pantanal: region with important biodiversity. This regions climatic conditions, hydrology and geomorphology as well as the existence of great variety of wild species favor the maintenance of the Leptospira in the environment. The aim of this study was to evaluate IgG ELISA with recombinant protein LipL32 in comparison with microscopic agglutination test (MAT) and additionally contribute to the knowledge of the distribution of the one of most important worldwide zoonotic infection, assessing the seropositivity of bovine leptospirosis in beef cattle herds of Brazilian Pantanal, an important ecological preserved area, where cattle constitute not only the most important economic resource but also the major activity compatible of the conservation of natural resource of the region. Out of 282 samples of cattle serum analyzed, 143 (50.71%) were positive in MAT. The serovar Hardjo (genotypic Hardjoprajitno and Hardjobovis), Wolffi and Ballum showed the largest frequency of reactive samples. In the IgG ELISA rLipL32, 161 samples (57.09%) were positive. This result was higher than obtained by MAT (p<0.001). The sensitivity of the ELISA test was 99.30% and the specificity was 86.33%, based on the MAT. This test was shown to be a more sensitive, specific and accurate test for the diagnosis of bovine leptospirosis compared to the MAT.

A fuzzy logic-based tool to assess beef cattle ranching sustainability in complex environmental systems

One of the most relevant issues in discussion worldwide nowadays is the concept of sustainability. However, sustainability assessment is a difficult task due to the complexity of factors involved in the natural world added to the human interference. In order to assess the sustainability of beef ranching in complex and uncertain tropical environment systems this paper describes a decision support system based on fuzzy rule-approach, the Sustainable Pantanal Ranch (SPR). This tool was built by a set of measurements and indicators integrated by fuzzy logic to evaluate the attributes of the three dimensions of sustainability. Indicators and decision rules, as well as scenario evaluations, were obtained from workshops involving multi-disciplinary team of experts. A Fuzzy Rule-Based System (FRBS) was developed to each attribute, dimension and general index. The essential parts of the FRBS are the knowledge database, rules and the inference engine. The FuzzyGen and WebFuzzy tools were developed to support the FRBS and both showed efficiency and low cost for digital applications. The results of each attribute, dimension and index were presented as radar graphs, showing the individual value (0-10) of each indicator. In the validation process using the WebFuzzy, different combinations of indicators were made for each attribute index to show the corresponding output, and which confirm the feasibility and usability of the tool.

Reproductive diseases serosurvey in dairy cattle from rural settlements of Corumbá city, Mato Grosso do Sul state, Brazil

This investigation was carried out in dairy cattle from four rural settlements of Corumba, MS, Brazil, in order to assess the seroprevalence of bovine herpesvirus 1 (BoHV-1), bluetongue virus (BTV), and Leptospira; and the prevalence was 50.9% (179/352), 51.3% (181/353), and 35.8% (125/349), respectively. Association between frequency of seropositive animals and evaluated rural settlements (P<0.01) was found for Leptospira, and indicated the influence of environmental factors in bovine infection. Age was significantly related to BoHV-1 (P<0.001), BTV (P<0.001), and Leptospira infection (P<0.01), showing higher number of infection among older animals. Once the bovine herds were not vaccinated, the presence of seropositive animals indicated that these infections occurred in rural settlements herds of Corumba assayed, and certainly induced economical loss.