The objective of the study was to determine the frequency of positive serology for canine erlichiosis (E. canis and E. ewingii) and anaplasmosis (A. phagocitophylum and A. platys) diseases in patients with presence or history of ticks during the period 2017-2018. The sample was composed of dogs who came to consultation to a private veterinary service in the city of Piura-Peru. These patients must have had presence or history of ticks, according to the owners. The information of the clinical signs that were presented at the time of the consultation and that could be compatible with the disease under study were collected in a medical card. Samples of 71 dogs were collected to be analyzed by blood count and a commercial test for the detection of these diseases (SNAP 4Dx- Idexx). It was determined that 55% (39 patients) presented antibodies against Erlichia spp. and 4% (3 patients) Anaplasma...