What Kind of Grapes & Raisins?
The source of the problem has been varied. Grapes of all varieties and growing conditions (including homegrown) have been implicated. Raisins are usually made from white seedless grapes, but all raisins of any source should be considered kidney toxic (chocolate covered raisins as well). Why? The toxic principle is unknown. Grapes contain low amounts of tannins compared to acorns, a known kidney toxicant in large animals. Grapes lack significant amounts of Vitamin D, another known kidney toxicant. It is unlikely pesticide residue is involved due to the wide variety of grape types involved. So far the majority of toxicosis reports have been in dogs. However, feeding grapes or raisins to cats and ferrets should also be discouraged, as poisonings have been reported in these species as well. How Many Would Poison Your Dog? The minimum toxic dose is approximately 0.3 oz/kg body weight. This would correspond to about 2 grapes per kg body weight, or roughly 1 grape per pound of body weight. 15