Evaluation histological, immunofluorescence and immunohistochemistry techniques for the postmortem diagnostic of the swine toxoplasmosis.

Abstract

Six 120 days old Landrace/Large-white swines with were inoculated with taquizoites of the AS 28, LIV-IV and N Toxoplasma gondii strains and analysed under clinical, sorological, parasitological and histopathological aspects. In order to evaluate some postmortem diagnostic techniques, three swines were sacrificed in the acute phase and three swines in the chronic phase of the infection. Formalin-fixed and parafin-embedded tissues were submitted to Eosin-Hematoxilin, Indirect Immunofluorescence (IFA) and Peroxidase Anti-Peroxidase (PAP) techniques. The Eosin-Hematoxilin showed to be efficient in the analysis of the morphological alterations in the tissues, but did not detect any form of the parasite. Both, IFA and PAP revealed taquizoites of T. gondii, although the last one showed to be more effective because it also allowed an analysis of the morphological tissue alterations.