Diagnostico de leptospira spp.utilizando as tecnicas de soroaglutinação microscopica e imunohistoquimica

Abstract

Leptospirosis has a worldwide distribution and is considered a major disease of cattle. The disease is responsible for economic losses both in the productive and reproductive. Thus, the survey was conducted in order to diagnose Leptospira spp. in cattle slaughtered in slaughterhouses-in São Luís - MA. Blood serum samples and placental tissue of 100 cows were not vaccinated against leptospirosis analyzed using the techniques of Microscopic Agglutination Test (MAT) and Immunohistochemistry (IHC). The study was conducted in 03 refrigerated slaughterhouses under Municipal Inspection. The blood samples and placental tissue were collected from females without clinical signs of leptospirosis over the age of 24 months. Of the 100 serum samples analyzed, 64% (n = 64) were positive, with titers equal or greater than 1:200, and 36% (n = 36) negative for all serotypes tested. Of the 24 serovars tested the most frequent in descending order were: Hadjo, and Grippotyphosa Wolffi. Of the 100 samples analyzed placental tissue by Immunohistochemistry technique, 40% (n = 40), were positive. Were considered positive reactions to the presence of filamentary material granular or homogeneous, with brown, diffusely distributed in the placental tissue, marked in different cell types. The sensitivity and specificity for IHC technique were 16% and 17%, respectively, which was statistically significant (P <0.05) between the techniques. The level of agreement between the SAM and IHC techniques was less than 0.20, indicating negligible degree of agreement. The frequency of anti-Leptospira spp. in cattle slaughtered in slaughterhouses-in São Luís - MA was high, with confirmation of the etiologic agent in 40% of samples. These findings indicate the necessity of systematic diagnosis and monitoring of flocks, and the implementation of control measures and prophylaxis, as gradual removal of infected animals, quarantine holding the entry of new properties in animals, serological tests, and vaccinations implementation of good hygienic practices in slaughterhouses-refrigerators.