Genetic diversity of piroplasmids species in equids from island of São Luís, northeastern Brazil

Abstract

Equine piroplasmosisis, a tick-borne disease caused by the intra-erythrocytic protozoans Babesia caballi and Theileria equi, has economic importance due to the international trade and the increased movement of horses all over the world. The goal of this study was to evaluate the occurrence of phylogenetic diversity of T. equi and B. caballi genotypes among infected equids from São Luís Island, state of Maranhão, northeastern Brazil. Between December of 2011 and June of 2012, EDTA-blood and serum samples were collected from 139 equids (90 donkeys, 39 horses and 10 mules). From 139 serum samples submitted to ELISA assay, IgG antibodies to T. equi and B. caballi were detected in 19.4% (27/139) and 25.2% (35/139), respectively. Among sampled animals, 21.6% (30/139) and 55.4% (77/139) were positive for cPCR assays for T. equi and B. caballi, based on ema-1 and rap-1 genes, respectively. Overall, the T. equi sequences (n=7) submitted to Maximum Likelihood analysis (based on a 18S rRNA fragment of 1700 bp after alignment) grouped into three main groups, which were subdivided in eight clusters. The present work showed that different genotypes of T. equi and B. caballi circulate among equids in Brazil.Keywords: Babesia caballi, Theileria equi, phylogeny, 18S rRNA. ResumoA piroplasmose equina, uma doença transmitida por carrapatos e causada pelos protozoários intra-eritrocíticos Babesia caballi e Theileria equi, tem importância econômica devido ao comércio internacional e ao aumento do movimento de cavalos em todo o mundo. O objetivo do presente estudo foi mostrar a diversidade filogenética de T. equi e B. caballi infectando cavalos, burros e jumentos na Ilha de São Luís, Estado do Maranhão, Nordeste do Brasil. Entre dezembro de 2011 e junho de 2012, amostras de sangue com EDTA e soro de foram coletadas de 139 equídeos (90 jumentos, 39 cavalos e 10 burros). Dentre as 139 amostras de soro submetidas ao ensaio de ELISA, foram detectados anticorpos IgG contra T. equi e B. caballi em 19,4% (27/139) e 25,2% (35/139), respectivamente. Entre os animais amostrados, 21,6% (30/139) e 55,4% (77/139) foram positivos por meio dos ensaios de cPCR para T. equi e B. caballi, com base nos genes ema-1 e rap-1, respectivamente. No geral, as sequências T. equi (n = 7) submetidas à análise de Máxima Verossimilhança (baseada em um fragmento do 18S rRNA de 1700 pb, após o alinhamento) foram agrupadas em três grupos principais, os quais foram subdivididos em oito grupos. O presente trabalho mostrou que diferentes genótipos de T. equi e B. caballi circulam entre equídeos no Brasil.Palavras-chave: Babesia caballi, Theileria equi, filogenia, 18S rRNA.

Serological detection and risk factors for equine piroplasmosis in the semiarid region of Pernambuco, Northeastern Brazil

“…The ELISA assay performed in this study revealed that, among the seroreactive horses, 34.9% tested positive for T. equi and 27.2% for B. caballi. These findings are consistent with those of two other studies conducted recently in northeastern Brazil, using ELISA, the first of which reported finding 43.5% of animals positive for T. equi and 7.7% for B. caballi, while the second study found 38.1% positive for T. equi and 18.6% for B. caballi (BRAGA et al, 2017;NOGUEIRA et al, 2017). In Paraíba, also in the country's northeastern region, a study using IFA found that 59.6% of horses were seroreactive to T. equi (FERREIRA et al, 2016).…”

“…Serological studies on B. caballi and T. equi have been conducted in the south, southeast and central-west regions of Brazil, which have revealed B. caballi prevalence rates varying from 18 to 90% (BARBOSA et al, 1995;HEUCHERT et al, 1999;HEIM et al, 2007;KERBER et al, 2009;VIEIRA et al, 2013;NOGUEIRA et al, 2017;BRAGA et al, 2017) and T. equi prevalence rates from 17 to 100% (TENTER & FRIEDHOFF, 1986;BARBOSA et al, 1995;RIBEIRO et al, 1999;HEUCHERT et al, 1999;XUAN et al, 2001;HEIM et al, 2007;GOLYNSKI et al, 2008;KERBER et al, 1999KERBER et al, , 2009BALDANI et al, 2010;SALVAGNI et al, 2010;VIEIRA et al, 2013;PROCHNO et al, 2014;VIEIRA et al, 2015VIEIRA et al, , 2018FERREIRA et al, 2016;GUIMARÃES et al, 2016;BRAGA et al, 2017;SCHEIN et al, 2018). However, such studies have rarely been carried out in northeastern Brazil.…”

Molecular survey and genetic diversity of piroplasmids in equids from Midwestern Brazil

“…Intraspecific analysis of the sequences obtained from equids of different ecoregions in the state of Mato Grosso showed 1.95% sequence divergence for B. caballi and 2.99% for T. equi. Studies based on ribosomal (18S) genes demonstrated variability between 0.5% and 2.1% for T. equi, allowing the segregation into different genotypes (BRAGA et al, 2017;PECKLE et al, 2018).…”

“…Within South America, the disease is readily identified in all regions, except for the southernmost areas of Chile and Argentina (WISE et al, 2013). In Brazil, previous studies using serological methods have shown that equine piroplasmosis is endemic, with prevalence rates varying from 19.4% to 100% (KERBER et al, 1999;HEIM et al, 2007;KERBER et al, 2009;BALDANI et al, 2010;SANTOS et al, 2011;MACHADO et al, 2012;TORRES et al, 2012;VIEIRA et al, 2013;PROCHNO et al, 2014;FERREIRA et al, 2016;GUIMARÃES et al, 2016;BRAGA et al, 2017).…”

“…Despite the endemicity of piroplasmosis among equids in Brazil, studies involving the molecular detection of the parasite in carrier animals (HEIM et al, 2007;BALDANI et al, 2010;PECKLE et al, 2013;MACHADO et al, 2012;BARROS et al, 2015;FERREIRA et al, 2016;BRAGA et al, 2017) that have also examined genetic diversity (BRAGA et al, 2017;PECKLE et al, 2018) are scarce. The aim of this study is to survey the distribution of piroplasmid (T. equi and B. caballi) parasites using molecular methods in equids from the Mato Grosso state and evaluate the interspecific genetic diversity.…”