Uso de ferramentas analíticas para o estudo da contaminação química por pesticidas e da ocorrência de vírus patogênicos em mamíferos silvestres no Sul do Brasil

Abstract

Wild aquatic and terrestrial mammals are at risk of extinction due to human action. The excessive use of chemicals in agricultural and industrial production has led to increasing environmental contamination, negatively impacting the lives of these animals. Furthermore, the proximity of domestic and wild animals due to increasing urbanization and intensive farming has also resulted in infectious diseases in wild mammals. Given the risks to these animals health, this thesis aimed to study chemical contamination by pesticides and the occurrence of pathogenic microorganisms in wild mammals in southern Brazil. The study populations were animals of the Order Carnivora, including pinnipeds, canids, and mustelids. The methods included chemical and microbiological analyses of biological material samples (fur, blood, tissues, etc.) collected from live and dead animals in southern Brazil. In the evaluation of the contamination by pesticides, the results demonstrated the presence of chemical residues in the fur of 20 (64.5%) animals from a total of 31 samples collected from pinnipeds (sea lions and fur seals) found dead in the coastal region of Southern Brazil. The most common chemical compounds were allethrin, azoxystrobin, bioallethrin, and triadimenol. In the analyses of the infection by pathogenic microorganisms, the occurrence of canine parvovirus was demonstrated in captive otters, including all animals positive with antibodies against this virus and one otter testing positive by PCR. The occurrence of parvovirus was also demonstrated in wild mammals and dogs found hit by cars (four positive dogs and five wild animals) on a highway in the same region. Finally, the conclusions on the topic are presented, demonstrating a worrying scenario in which both impacts (pollution and disease spread) constitute risk factors for wild populations and favor imbalance and consequent environmental and health impacts. [resumo fornecido pelo autor]