Ehrlichia canis in dogs in a semiarid region of Northeastern Brazil: serology, molecular detection and associated factors - Tanikawa, A; Labruna, Marcelo Bahia; Costa, A; Aguiar, D. M; Justiniano, S. V; Mendes, R. S; Melo, A. L. T; Alves, C. J; Azevedo, S. S (Research in Veterinary Science, 2013)