Tick-borne diseases serology. Many retired or actively racing greyhounds have been exposed to a variety of tick-borne rickettsial organisms (Babesia canis, Babesia gibsoni, Ehrlichia canis, Ehrlichia platys, Rickettsia rickettsii). Adult racing and adopted former racers rarely show clinical signs of these diseases, but relatively often have low, moderate or even very high babesia and/or rickettsial antibody titers on serologic tests, indicating prior exposure to the organism(s). The most commonly seen antibody titers are to B. canis and E. canis. It has been estimated that as much as 70% of greyhound stock of the southern United States and Mexico will be babesia and/or ehrlichia antibody-positive. Many retired, adopted greyhounds are being screened for these diseases because of the common misperception among adoption groups that a positive serologic test for antibody equates with disease or disease risk. (The same well-meaning national effort also promotes thyroid testing and treatment of any greyhound with thyroid levels that appear below or at the lower end of the general reference ranges for dogs. This has led to prescribing large overdoses of thyroid supplement in a futile attempt to increase blood thyroid levels to the expected therapeutic ranges for other breeds.)

Greyhounds that remain healthy on physical examination and show no evidence of hemoparasites on thorough examination of the feathered edges of blood smears generally do not need to be treated for rickettsial diseases, especially babesiosis, on finding mild to moderately high antibody titers. Although imidocarb diproprionate has become licensed for use in this country, it is expensive and can produce occasional, serious adverse reactions. It would be unwise, therefore, to treat asymptomatic antibody-positive dogs as a routine policy. If they are to participate in a blood donor program, however, they should be seronegative or have only low antibody titers (e.g. < 1:160 for Babesia spp; < 1:40 for Ehrlichia or Rickettsia spp).

References: Beale KM et al, JAAHA 196:263-269, 1991; Taboada J et al, JAVMA 200:47-50. 1992; Sullivan PS et al, JAVMA 205:838-844, 1994; Dodds WJ, JAVMA 206:1312, 1995; Current Concepts Editorial, JAVMA 206: 1689-1693, 1995; Cowan LA et al, J Vet Int Med 11(2):142, 1997; Burkett G, Vet Med 95:115-124, 2000; Gaughan KB, Bruyette DS, AJVR 62:1130-1133, 2001; Hill RC et al, AJVR 62:1969-1972, 2001.

Lepto Profile. Test Code T16510. Measures L. canicola, L. hardjo, L. pomona, L. grippotyphosa, and L. icterohemorrhagia. Cost: $40.25

Lepto Profile Plus. Test Code 85604. Measures the serovars listed above, plus L. bratislava and L. autumnalis. Cost $58.75