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Licensed Unlicensed Requires Authentication Published by De Gruyter April 18, 2017

Toxoplasma gondii in backyard pigs: seroepidemiology and mouse bioassay

Erika Fernanda Torres Samico-Fernandes, Marcela Fernanda Torres Samico-Fernandes, Pedro Paulo Feitosa de Albuquerque, Jonatas Campos de Almeida, André de Souza Santos, André da Rocha Mota, Orestes Luiz de Souza Neto and Rinaldo Aparecido Mota
From the journal Acta Parasitologica


The aim of this study was to evaluate the occurrence of Toxoplasma gondii in backyard pigs destined for human consumption in Pernambuco state, Brazil. Blood and tissue samples (liver, heart, brain, lung and diaphragm) were collected from 224 pigs from legal slaughterhouses and tested for T. gondii infection. Antibodies to T. gondii were found in the sera of 37.9% (85/224) by using the immunofluorescence antibody test (cut-off – 1:64). Tissue samples from seropositive pigs were bioassayed in mice. Tissue samples from seropositive pigs and from mice of the bioassay were submitted to histopathology, immunohistochemistry, polymerase chain reaction (PCR) and sequencing; 14.1% of pig tissue samples and 27.7% of bioassayed mouse samples were positive for T. gondii DNA, but all pig and mouse tissues were negative in histopathology analysis and immunochemistry. By using a risk assessment questionnaire, there was significant difference (p<0.001) in seroprevalence of 21.2% (reproducer) and 3.1% (finishing pig). These data serve as indicative of the sanitary conditions and risk of T. gondii infection for backyard pigs. Preventive measures must be implemented by health services to avoid toxoplasmosis human cases due to ingestion of pig meat.

  1. Conflict of interest statement The authors declare that no competing interests exist.


The authors would like to thank the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and the Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco (FACEPE) for their financial support for this project (APQ 1492-5.05/12).


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Received: 2016-11-29
Revised: 2017-1-20
Accepted: 2017-2-20
Published Online: 2017-4-18
Published in Print: 2017-6-1

© 2017 W. Stefański Institute of Parasitology, PAS

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