Garlic & Dogs Pt1 - Page 1

EFFECTS OF CULTIVATED GARLIC ON CANINE HEMATOLOGIC PARAMETERS Am I Vet Res. 2001;67:1446-1450. Lee KW, Yamato O, Tajimi M, et al. Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan As people become more comfortable using nutritional supplements in their diets, they are often tempted to make similar additions to the diets of their pets in an effort to share the health benefits that supplements offer. Unfortunately, it is never wise to assume that a compound safe for humans is also safe for pets. Garlic is a popular food and dietary supplement believed to improve cardiovascular health and lower cholesterol levels. Garlic belongs to the same family as onions, which contain both n-propyl disulfide and 3-alk(en)yl thiosulfate, and are known to cause hemolytic anemia in dogs. Over- the-counter garlic tablets offer a concentrated source of garlic extract without the strong taste and odor and could be readily administered to dogs. While wild garlic has been shown to produce the same hemolytic effects as onions in dogs, it is unclear whether ordinary cultivated garlic also triggers hemolytic processes. This study was designed to evaluate the effects of concentrated cultivated garlic extract on hematologic parameters in dogs. Eight adult mixed-breed dogs were randomly assigned to either treatment (four dogs) or control (four dogs) groups. To prepare the extract, bulbs of garlic were peeled and homogenized. The homogenate was filtered through gauze, and the filtrate was boiled. After being filtered a second time, the filtrate was allowed to evaporate until it reached a volume of 0.25 mL/g of whole garlic. Dogs in the treatment group received 1.25 mL garlic extract/kg body weight through a nasogastric tube once daily for seven days. Control dogs were tubed with an equal volume of water. Blood samples were drawn before treatment, then daily for 10 days and on days 12,15, 20, and 30. Erythrocyte, leukocyte, and platelet counts were conducted, and methemoglobin (MetHg) and reduced glutathione (GSH) concentrations were measured. Examination for erythrocyte morphology and presence of Heinz bodies was also completed. All of the dogs treated with garlic extract experienced hemolysis, although none demonstrated clinical signs of hemolysis or hemoglobinuria. Erythrocyte counts in treated dogs were significantly lower than those in control dogs when compared with pretreatment values. The lowest erythrocyte counts were seen three days after the last dose of garlic extract was administered (6.85 +/- 0.92 x 106 cells/uL; pretreatment mean =3D 8.52 +/-0.37 > 106 cells/uL). In addition, erythrocyte counts remained low in treated dogs from days 7 to 20. Both hematocrit and hemoglobin concentrations were also significantly decreased in treated dogs. Leukocyte counts revealed a prominent leukocytosis in treated dogs due to an increased number of neutrophils. A similar change in white blood cells has been seen with onion-induced hemolytic anemia, although the mechanism is unknown. Platelet counts were unchanged.