Hepatozoon canis gametocytes were identified in circulating neutrophils of 3 dogs from different parts of Texas. Clinical signs included intermittent fever, stiffness, and inappetence. The dogs had marked neutrophilic leukocytosis (35,000--51,000/mm3). Parasitemia varied from less than 1% to 60% of the circulating neutrophils. Two of the dogs had periosteal new born reaction on the vertebrae, ilia, ribs, and bones of the limbs proximal to the carpus and tarsus. There was no evidence that specific drug therapy was of value, although use of corticosteroids, aspirin, and antimicrobial agents was accompanied by clinical improvement.