Factors associated to Theileria equi in equids of two microregions from Rio de Janeiro, Brazil

Abstract

Serum samples from 714 equids of Itaguaí and Serrana microregions, Rio de Janeiro, southeastern Brazil, were examined by indirect fluorescent antibody test (titer 1:80) for Theileria equi. The prevalence in the microregions and factors associated with seropositivity were evaluated and the prevalence ratio (PR) calculated. The overall prevalence of T. equi infection was 81.09% (n = 579), with higher prevalence (p < 0.05) in the Itaguaí (85.43%) when compared to Serrana microregion (76.92%). The geographic area, altitude, farming condition and area of origin of equids were associated (p < 0.05) with seropositivity for T. equi. Equids reared in the Itaguaí microregion (PR = 1.11, p = 0.003) and at altitudes below 500 m (PR = 1.10; p = 0,014) were more likely to be seropositive for T. equi. Furthermore, when equids were born in the farm (PR = 1.10, p = 0.008) and reared with poor farming conditions (PR = 1.13, p = 0.018) they were more likely to be exposed to T. equi. The main ticks found on equids were Amblyomma cajennense and Dermacentor (Anocentor) nitens. The microregions studied are endemic areas for equine theileriosis and there exists enzootic stability for T. equi. Only factors related to the collection area of serum samples influenced the seropositivity of equids for T. equi in that region.Keywords: horses, equine theileriosis, IFAT, prevalence, epidemiology. ResumoAmostras de soro de 714 equídeos das microrregiões de Itaguaí e Serrana, Rio de Janeiro, Brasil, foram submetidas ao teste de imunofluorescência indireta (título 1:80) para Theileria equi. A prevalência entre as microrregiões e os fatores associados à soropositividade foram avaliados e a razão de prevalência (RP) calculada. A prevalência geral para T. equi foi de 81,09% (n = 579), com maior prevalência (p < 0,05) para microrregião de Itaguaí (85,43%), quando comparado a Serrana (76,92%). A região, altitude, nível da propriedade e origem dos equídeos foram associados (p < 0,05) com a soropositividade para T. equi. Equídeos criados na microrregião de Itaguaí (RP = 1,11; p = 0,003) e em altitudes abaixo de 500 m (RP = 1.10; p = 0,014) apresentaram maior chance de se tornarem soropositivos para T. equi. Além disso, quando são criados em propriedades de nível ruim (RP = 1,13; p = 0,018) e nascidos na propriedade (RP = 1,10; p = 0,008) apresentaram mais chance de terem contato com T. equi. As principais espécies de carrapatos encontradas parasitando os equídeos foram Amblyomma cajennense e Dermacentor (Anocentor) nitens. As microrregiões estudadas são endêmicas para theileriose equina e de estabilidade enzoótica para T. equi. Apenas os fatores relacionados à área de coleta das amostras de soro influenciaram a soropositividade dos equídeos para T. equi naquela região.Palavras-chave: equinos, theileriose equina, RIFI, prevalência, epidemiologia.

Molecular epidemiology of Theileria equi in horses and their association with possible tick vectors in the state of Rio de Janeiro, Brazil

“…This epidemiological study reinforces the endemic character that equine theileriosis assumes in Brazil (Pfeifer-Barbosa et al 1995; Heuchert et al 1999; Golynski et al 2008; Kerber et al 2009; Santos et al 2011). In addition, this study highlights the possible factors relevant to properties, breed management, and animal characteristics that are associated with T .…”

“…equi in the horses, a semi-structured questionnaire about the horses and the breeding and property management characteristics was administered to the owners. The factors investigated by the questionnaire were organized as follows: municipalities of Seropedica (low-altitude regions, less than 400 m in elevation) or Petropolis (high-altitude regions, more than 400 m in elevation); satisfactory or unsatisfactory zootechnical and sanitary management (Santos et al 2011); presence or absence of ticks on animals; horses bred in close contact with cattle (cattle and horses shared the same pasture or were located close in proximity) or without contact with cattle; confined breeding system (confined system: animals had no access to outside areas and were restricted to the bay) or semi-confined/extensive system (limited access or total access to pasture areas); activities of the horses (sport/exhibition; work/walk or recreation; reproduction); gender (male or female); age (≤ 2 years old or > 2 years old); racial definition (breeded horses or mixed-breed horses).…”

Seroprevalence rates of antibodies against Theileria equi in team roping horses from central-western region of Paraná

“…These results shows that T. equi is widespread in the region studied, suggesting high levels of transmission. Additionally, our data is in accordance with previous studies which have demonstrated that the disease is endemic in Brazil (CUNHA et al, 1996;BALDANI et al, 2004;HEIM et al, 2007;SANTOS et al, 2011;PECKLE et al, 2013). To our knowledge, this is the first report of the detection of IgG antibodies anti-T. equi in Paraná state.…”

Multiplex PCR for detection of Trypanosoma evansi and Theileria equi in equids of Punjab, India

“…As donkeys/mules were mainly kept in open yard under poor managemental conditions, hence they are at more risk with respect to vector (OR=4,12.35) resulting in haemoparastic infection. Moreover, due to the small sample size of donkeys/mules, the higher prevalence of infection in donkeys/mules compared to Thoroughbred horses need more investigations on larger sample size (Kouam et al, 2010;Dos Santos et al, 2011). In this study a marked difference in infection rate of equids less than 2 year of age as compared to adults was observed.…”