Phylogenetic position of Theileria cervi detected in Blastocerus dichotomus (Artiodactyla: Cervidae) with clinical symptoms from Argentina

Abstract

The results of this study document the molecular detection of Theileria cervi in a symptomatic adult marsh deerBlastocerus dichotomus (Artiodactyla: Cervidae) from Argentina and characterize the phylogenetic position ofthe Argentinian strain. The animal was founded with signs of obnubilation, anaemia, and ataxia on IslaTalavera in the Paraná Delta, Argentina. Biochemical, haematological and post mortem histopathological studiesresulted in the detection of symptoms associated with Theileria infections. Piroplasmid DNA was detected ina blood sample and the complete 18S rDNA gene sequence could be archived. Phylogenetic analyses of theobtained sequence verify the genetic relationship of the Argentinian strain with strains of T. cervi found in otherdeer species in North America. This result, together with reports of T. cervi detected in various deer species thatinhabit countries from Canada in the North to Argentina in the Western Hemisphere, indicates that thisPiroplasmorida possess a low host specificity. Although the majority of T. cervi infections results asymptomaticor in mild course of the disease, it must be considered that T. cervi is circulating in Argentinian B. dichotomuspopulations and can cause serve course of the disease. Therefore, further studies are needed to investigate itsprevalence, distribution and veterinary impact.