Toxoplasma gondii: diagnosis of experimental and natural infection in pigeons (Columba livia) by serological, biological and molecular techniques

Abstract

<jats:p>This study aimed to diagnose experimental and natural Toxoplasma gondii infection in pigeons (Columba livia) by serological, biological and molecular techniques. Twelve pigeons, free of infection, were inoculated with 50 sporulated oocysts of T. gondii (VEG sample) and four remained uninfected controls. Four birds (three infected and one control) were euthanized at 15, 30, 45 and 60 days post-infection (dpi), and their tissues were used to perform a bioassay in mice and nested-PCR using B1 gene as target. Blood was obtained weekly and it was tested for the presence of anti-T. gondii antibodies by the indirect fluorescent antibody test (IFAT) and modified agglutination test (MAT). Seven (58.3%) out of 12 inoculated pigeons were positive by serological techniques and titers ranged between 1:40 and 1:5120 by MAT and between 1:512 and 1:4096 by IFAT. Complete agreement was seen between the results obtained by serological techniques and nested-PCR in seven positive birds. In the bioassay in mice, five (41.7%) out of 12 pigeons inoculated were positive to T. gondii. Only one pigeon died at 23 dpi due to toxoplasmosis. A second study with free-living pigeons was performed for detection of anti-T. gondii antibodies. Birds were captured in the municipalities of São Paulo, Ibiúna and Sorocaba, São Paulo State, Southeastern Brazil. All 126 free-living birds were negative to anti-T. gondii antibodies by MAT (titer &lt; 1:5). Bioassays were performed in mice with tissues from all captured birds and T. gondii was not isolated in any pigeon.</jats:p>

Genetic characterization of Toxoplasma gondii isolates from eared doves (Zenaida auriculata) in Brazil

“…Other studies in Brazil that used C. livia observed lower seroprevalence, which ranged from 0 to 5% (GODOI et al, 2010;SOUSA et al, 2010;LIMA et al, 2011). There was a statistically significant difference in the present study regarding the capture sites.…”

“…The presence of type II has been reported in guinea fowl and cattle in Brazil (DUBEY et al, 2011;MACEDO et al, 2012). Previous studies on free-living pigeons (C. livia) in Brazil did not obtain T. gondii isolates (GODOI et al, 2010;LIMA et al, 2011). However, using the PCR-RFLP method, Alvarado-Esquivel et al (2011) classified the isolate from the pigeon C. livia in Mexico as atypical, thus confirming the genotypic variability of non-European and American isolates.…”

Ocorrência de anticorpos anti-Toxoplasma gondii em aves silvestres de três Unidades de Conservação Federais da Paraíba e da Bahia

“…No Estado de São Paulo também foram realizados levantamentos sorológicos em outras aves sinantrópicas no estudo feito por Godoi et al (2010) examinando populações de pombos-domésticos (Columba livia), sendo encontrados 0% (0/126) de soropositivos para anticorpos anti-T. gondii pelo MAT (título 1:5) nas cidades de São Paulo, Ibiúna e Sorocaba e em 5% (12/238) de soropositivos pelo MAT (título 1:8) nas cidade de São Paulo (De Lima et al 2011).…”

“…As pesquisas foram realizadas na região Sudeste no Estado de São Paulo (Sogorb et al 1972, Sogorb et al 1977, Gonçalves et al 2013) e na região Nordeste no Estado da Bahia (Gondim et al 2010) e no Estado de Pernambuco, estudos foram realizados no continente (Vilela et al 2011) e no Arquipélago de Fernando de Noronha (Costa et al 2012). Em pombos-domésticos (Columba livia) sinantrópi-cos fo-ram realizados levantamentos sorológicos no Estado de São Paulo (Godoi et al 2010, De Lima et al 2011. Todas estas pesquisas foram realizadas em áreas próximas de cidades e de granjas de aves domésticas, e a participação das aves silvestres como hospedeiro intermediário de T. gondii em Unidades de Conservação ainda é pouco compreendida, o que justificou a realização desta pesquisa.…”

Prevalence of Antibody to Toxoplasma gondii in Black-headed Gulls (Chroicocephalus ridibundus), Dianchi Lake, China

“…gondii antibodies in birds including the indirect hemagglutination test (IHAT; Yan et al 2010), latex agglutination test (LAT; Martínez-Carrasco et al 2004), enzymelinked immunosorbent assay (ELISA; Zhang et al 2000), and indirect fluorescent antibody test (IFAT; Godoi et al 2010). However, MAT is considered one of the most effective assays for detecting avian infection by T. gondii.…”