Equine Piroplasmosis

Babesiosis is described as the main parasitosis affecting equines due to the direct and indirect effects it causes to the health of these animals (FRIEDHOFF, 1988). The economical implications associated with equine babesiosis include the cost of the treatment, especially of animals presenting acute infections, abortion, impaired performance, death and restrictions related to international trade and participation in equine competitions (GUIMARÃES et al., 1997; MARTIN, 1999). The disease is transmitted by ticks and caused by parasites located inside the erythrocytes. It may be caused by different protozoa: Babesia equi (or Theileira equi) and Babesia caballi. Horses may be parasited by one of both species of babesia at the same time (MELHORN e SCHEIN, 1998). Babesiosis affects equines, mules, donkeys and zebras (PURNELL, 1981). The disease is endemic in many tropical and subtropical areas of the world, as well as in temperate zones (SCHEIN, 1988; BRÜNING, 1996). Due to the fact that it is still undefined, the taxonomy of Babesia equi has been largely investigated during the last years. Some authors describe that the family Piroplasmidae should include Babesia caballi and the genus Theileria equi (not Babesia equi), once, different from other babesia species, the latter begins its cycle inside lymphocytes before it parasites erythrocytes, and divides into four merozoites, as some Theileria species. […]