Pesquisa de Rickettsia em equinos do grupamento racial “cavalo baixadeiro” e em ectoparasitas potencialmente vetores de patógenos, na microrregião da Baixada Maranhense, Maranhão, Brasil

Abstract

Native horses from the microregion of the “Baixada Maranhense” are called “cavalo baixadeiro” and are created predominantly in the fields, without health and nutritional management, predisposing them to variety diseases, especially parasitic diseases. The aim of the present study was to detect Rickettsia and identify ectoparasites which have potential in transmitting of the pathogens to “cavalo baixadeiro”. To search Rickettsia were sampled 258 horses subjected to the same management, 37 (14.34%) of the municipality of Santa Helena, 60 (23.26%) of Viana and 191 (62.40%) of Pinheiro. Of these 64.34% were females and 35.66% were males. Of the total samples submitted to IFA, 152 (58.91%) reacted at least to one of the antigens tested (Rickettsia rickettsii, Rickettsia amblyommii and Rickettsia bellii). It was found only tick infestation in 220 (85.27%) animals by one or more species. The following species were identified, Dermacentor nitens (98.64%), Amblyomma cajennense (4.55%) and Rhipcephalus (Boophilus) microplus (1.82%). A Polymerase Chain Reacti on (PCR) was performed in115 ticks as follows: 92 specimens of D. nitens, 18 A. cajennense and five of R. (B.) microplus. Three samples of Amblyomma cajennense were positive for the gltA and OmpA genes. The samples were sequenced and showed 100% similarity to R. amblyommii.