Interface da caracterização morfológica de lesões causadas por larvas de Taenia saginata com o diagnóstico da cisticercose bovina

• Autor(a) principal: Peixoto, Rafaella Paola Meneguete dos Guimarães
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5100
• topic: Cisticercose bovina; Morfologia; Diagnóstico; ELISA; Bovine cysticercosis; Morphology; Diagnosis; ELISA; CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA::INSPECAO DE PRODUTOS DE ORIGEM ANIMAL

The bovine cysticercosis is a zoonotic disease that causes damage both in terms of health and in terms of economy. This research was developed in order to better understand the anatomical and microscopic characteristics related to the implantation of cysticerci and the immune evolution of the disease, and evaluate the performance of the immunoassay ELISA in the diagnosis of nine experimentally infected animals by oral administration of Taenia saginata eggs. Field work with the animals included the monthly collection of blood every 30 days, being that from 120 days post-infection an animal was slaugthered every 30 days to perform the anatomic-pathological examination and proceed with the collection of cysticerci. The samples from naturally infected animals were obtained by collecting in commercial slaughterhouse. Regarding muscular location of cysticercus in Group 1, the sites routinely inspected with predominance of occurrence were the heart (37.7%), head muscles (17.1%) and the tongue (2.3%). In relation to the assessed commercial cuts, 8.2% of cysticerci were found in the sparerib, 6.6% in the shoulder, 6.2% in the tenderloin and 5.8 in the rump. Other not-routinely inspected tissues that presented cysticerci were the diaphragm, the liver and the esophagus with 2.7%, 12.0% and 1.2% of the total cysticerci. Not viable cysticercus was the majority in head muscles (77.3%), followed by 76.3% in heart muscle and 71.0% in the liver and tongue (50%). Concerning viability, liver presented 87.5% of the not viable cysticerci, followed by the tongue 66.7%, and the heart with 63.2%, but the highest frequency of viable cysticerci was found in the head muscles (68.3%). Of the nine animals studied, five had the kinetics of antibody production against the cysticerci in a similar way when measured the production of antibodies of the IgM and IgG classes, once the peak of antibody production occurred in the period of 0-30 days post-infection followed by a natural decline and maintained detectable until the end of the study. However, the other two groups, each containing two animals, showed the kinetics of antibody production different from most animals, being that one group had a delayed response to the presence of cysticerci and the other group showed no immune response against antigens secreted by cysticerci. For the production of IgG1, it was possible to detect increased levels of antibodies from 30 days post-infection, having the production peak at 270 days, and IgG2 at 60 days. Regarding the cellular response observed against the cysticerci, it was possible to observe that in the case of viable cysticerci, inflammatory cells were present in the major part; and in the case of unviable cysticerci, the presence of repairing tissue cells, being also correlated the amount of calcareous corpuscles with the parasite's stage of death. With regard to the performance of the ELISA test against experimentally and naturally infected animals using a cut-off 1 and 2 added with 2 standard-deviation (SD), it was of 12% and 24.4%, respectively; and when using the cut-off 1 and 2 added with 3 SD the test sensitivity was at 1.99% and 14.4%, respectively. As for the samples from experimentally infected animals using the cut point 1 and 2 added with 2 SD the sensitivity was at 55.9% and 92.5%; and adding 3 SD the values found were 31.2% and 86%, respectively; the specificity of the test in all situations tested was at 100%. The combination of these results should be considered for diagnosis of bovine cysticercosis through the ELISA test, suggesting its use in combination with the anatomic-pathological test routinely performed in slaughterhouses.