RESUMO
The intestinal protozoan parasite Giardia duodenalis (syn. Giardia intestinalis and Giardia lamblia) is a widespread enteric pathogen in human and domestic animals. This organism is one of the most common parasites in domestic dogs in Brazil. In this study, we determined the occurrence and genetic characterization of G. duodenalis isolated from dogs from south-central São Paulo state, Brazil. A total of 300 fecal samples were collected. Fecal specimens were screened for the presence of G. duodenalis using microscopy (zinc sulfate solution flotation technique) and polymerase chain reaction (PCR) targeting the small subunit ribosomal (SSU-rDNA) and glutamate dehydrogenase (GDH) genes. Genetic characterization was performed using restriction fragment length polymorphisms (RFLP) and sequencing analysis of the GDH gene. In addition, selected samples were further characterized by RFLP and sequencing of the ß-giardin gene. The overall occurrence of G. duodenalis was 17.3% (52/300). The occurrence was higher in stray dogs (28%) than in household dogs (6.25%). Of the 36 PCR-positive samples that were selected for genotyping, only dog-specific genotype C (20 isolates), D (11 isolates) and mixed C + D (five isolates) isolates were detected in the study. This study provides current information on the infection rates of G. duodenalis genotypes in canine populations and describes for the first time the presence of mixed infections within host-specific C and D genotypes in dogs in Brazil. These genotypes were widespread and commonly found in domestic dogs living in urban and suburban environments of the studied area and confirmed the endemic status of Giardia in this region.
Assuntos
Doenças do Cão/parasitologia , Giardia lamblia/classificação , Giardia lamblia/genética , Giardíase/veterinária , Animais , Brasil , Proteínas do Citoesqueleto/genética , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Cães , Fezes/parasitologia , Genes de RNAr , Giardia lamblia/isolamento & purificação , Giardíase/parasitologia , Glutamato Desidrogenase/genética , Microscopia , Dados de Sequência Molecular , Tipagem Molecular , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Proteínas de Protozoários/genética , RNA de Protozoário/genética , RNA Ribossômico/genética , Análise de Sequência de DNARESUMO
With the object of determining the occurrence and prevalence of parasites in dogs and cats in the region of Botucatu, a survey was conducted from the results of fecal parasitologic exams feces, processed by the laboratory of parasitic diseases of FMVZ-UNESP/Botucatu from January 2002 to December 2006. 1,012 fecal samples of dogs and cats were evaluated by the technique of Willis Mollay and Faust. In dogs the higher incidence was found for Ancylostoma caninum eggs (38%). In cats, the oocysts of Isospora spp were present in 48.38% of positive samples.