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This study reports for the first time molecular detection of Anaplasma platys infection in 4 (13.3%) of 30 Malaysian dogs investigated. A low occurrence (3.3%) of Babesia gibsoni was also noted, being detected in one of the 30 dogs. Rickettsia, Bartonella, Orientia tsutsugamushi, and Ehrlichia DNA were not detected in the dog blood samples. The role of A. platys as an agent of canine anaplasmosis and its transmission through Rhipicephalus sanguineus ticks merits further investigation. Anaplasma platys (formerly Ehrlichia platys) is an obligate intracellular bacteria of the family Anaplasmataceae which causes infectious canine cyclic thrombocytopenia (ICCT) in dogs. The organism was first reported in 1978 in Florida (Harvey et al., 1978). Since then, it has been reported in many geographical regions (Arraga-Alvarado et al., 2003; de la Fuente et al., 2006). Anaplasma platys can be transmitted through the bite of an infected tick (Rhipicephalus sanguineus) (Arraga-Alvarado et al., 1997; Harvey, 1993; Hibler et al., 1986). Although ICCT is considered a benign disease without obvious clinical signs (Arraga-Alvarado et al., 2003) by most investigators, severe infections such as uveitis and pancytopenia have been reported (Glaze et al., 1986; Arraga-Alvarado, 1992). Identification of A. platys morulae, seen as inclusion bodies in blood smears, is challenging due to the cyclic parasitemia nature of the disease (Breitschwerdt, 2000). Serological approaches are useful to determine the degree of exposure but are not able to differentiate the causative species as cross-reactivity of A. platys with other Anaplasma has been reported (Beaufils et al., 2002). Therefore, molecular method is essential for accurate detection of A. platys when parasitemia is low and for strain differentiation of the infecting strain. Up to now, there was no report yet on A. platys infection in dogs in Malaysia. Canine babesiosis causes hemolytic anemia, thrombocytopenia, lethargy, and splenomegaly in infected dogs. The disease has been classified as a clinically significant tick-borne haemoprotozoan disease worldwide (Irwin, 2009). Based on microscopic analysis of blood smears, a survey conducted between 1973 and 1981 in Selangor, Malaysia, documented the identification of Babesia gibsoni and Babesia canis from 17.7% and 1.1% of dogs, respectively (Rajamanickam et al., 1985). The availability of advanced molecular methods such as polymerase chain reaction