Isolamento e caracterização biológica e genotípica de Toxoplasma gondii de aves e mamíferos silvestres de Pernambuco, Brasil

Abstract

Toxoplasma gondii is a wide world distribution parasite and has a clonal population structure. Recent studies have shown greater genetic variability of this protozoan in Brazil in domestic and wild animals, needing more research with this last group. The aim of this study was to isolate and make genotypic characterization of Toxoplasma gondii in tissues of naturally infected wild mammals and birds, from free ranging and captivity at Pernambuco, and verify antibodies occurrence against this parasite in samples were sera was obtained. From 2014 March to 2015 September, 233 biological samples were collected from 113 birds and 120 mammals. Considering origin, 77 animals were from free ranging and 156 were from captivity, from a zoo and a wildlife rehabilitation center. Serological exam was performed in 165 animals (59 birds and 106) mammals) by Modified Agglutination Test (MAT). In 105 animals there was gathering of heart, brain, skeletal muscle and diaphragm fragments. From those 105 samples, 32 were submitted to mouse bioassay and 73 were submitted to direct molecular diagnosis by PCR from a fragment of B1 gene 155-pb. For virulence analysis, mice used in bioassays were evaluated for four weeks in search of toxoplasmosis clinical signs. Positive samples of wild animals and mice were submitted to genotyping by PCR-RFLP technique, using markers SAG1, 5’3’SAG2, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, Apico and CS3. Anti-T. gondii antibodies were found in 52,7% (87/165) of the samples, with higher percentages in captivity animals (61,6%, 78/125), than in free ranging ones (22,5%, 9/40). In bioassays, one non virulent sample was isolated, of genotype #13 from a free ranging striated heron (Butorides striata) from Recife. From the 73 primary samples submitted to PCR, seven were positive, with identification of genotype Type BrIII in a captive tropical otter (Lontra longicaudis). Both genotypes identified corroborate with the existence of genetic variability of T. gondii in Pernambuco. Two blonde capuchin monkeys (Sapajus flavius) positive by PCR had necropsy findings compatible with death by acute toxoplasmosis. The enhancement of preventive veterinary medicine and biosecurity programs for toxoplasmosis must be performed in institutions that keep captive wildlife.