Serological survey on Ehrlichia sp. among dogs in the central region of Rio Grande do Sul

Abstract

A serological survey on Ehrlichia canis was conducted among dogs in the central area of the state of Rio Grande do Sul, where the tick Rhipicephalus sanguineus is a common parasite of dogs. Out of a total of 316 dogs attended at the veterinary teaching hospital in the municipality of Santa Maria, only 14 (4.43%) reacted positively to E. canis antigens in the indirect immunofluorescence assay, with the following endpoint titers: 80 (three dogs), 160 (five), 320 (four), 640 (one) and 1280 (one). Like in previous studies in other regions of the state of Rio Grande do Sul, only a very small portion of the dogs in Santa Maria presented antibodies reactive to E. canis, even though canine infestations due to R. sanguineus are very common in this study region. These results contrast with other regions of Brazil, where E. canis is endemic among canine populations, with seropositivity values generally higher than 30%. Genetic differences among the R. sanguineus populations in South America might be implicated in these contrasting results.

Rangelia vitalii, Babesia spp. and Ehrlichia spp. in dogs in Passo Fundo, state of Rio Grande do Sul, Brazil

“…This may have occurred in the present study or, furthermore, the dogs may have previously been in contact with agents of the genus Babesia or the family Anaplasmataceae. The serological results for E. canis were similar to those described by Krawczak et al (2012), who found that only 4.43% of the dogs were seropositive for this agent in the central region of Rio Grande do Sul. This demonstrated that there was low prevalence of anti-E. canis antibodies, despite the presence of R. sanguineus ticks in the dogs.…”

“…B. vogeli is the canine babesiosis agent most commonly reported, with seroprevalence ranging from 18.8% to 73.3% (TRAPP et al, 2006;FURUTA et al, 2009;SPOLIDORIO et al, 2010). A serological study involving 316 dogs that was conducted in the central region of the state of Rio Grande do Sul, Brazil, showed that only 4.43% of the animals presented antibodies to E. canis according to the indirect fluorescence antibody test (IFAT), although infestation by the tick R. sanguineus is common in this region (KRAWCZAK et al, 2012). Seropositivity for the causative agent of canine monocytic ehrlichiosis has been found to range from 0.7% to 86.2% among several regions of Brazil (VIEIRA et al, 2013).…”

Survey of Ehrlichia canis, Babesia spp. and Hepatozoon spp. in dogs from a semiarid region of Brazil

“…Plasma samples were initially tested at a screening dilution (1:80) (KRAWCZAK et al, 2012) and then re-tested with serial two-fold dilutions of up to 1:1280. A commercial fluorescein-labeled rabbit anti-canine IgG (Sigma-Aldrich, 3050 Spruce St. Louis, MO 63103, USA) was used as the secondary antibody.…”

Canine ehrlichiosis: prevalence and epidemiology in northeast Brazil

“…This bacterium mainly parasitizes the cells of the mononuclear phagocyte system and causes clinical and hematological abnormalities such as fever, anorexia, vomiting, diarrhea, petechial hemorrhages, anemia, and thrombocytopenia (MOREIRA et al, 2003). Canine monocytic ehrlichiosis is found in many tropical and subtropical countries and is found in all regions of Brazil (AGUIAR et al, 2007;ALBERNAZ et al, 2007;AZEVEDO et al, 2011;CARLOS et al, 2007;CARVALHO et al, 2008;KRAWCZAK et al, 2012;MUNDIM et al, 2008;SILVA et al, 2010). Some factors may predispose dogs to disease development, such as older age, the presence of and contact with other dogs, living in urban habitats, and exposure to R. sanguineus parasitism (AZEVEDO et al, 2011;FAIERSTEIN et al, 2008).…”