Grape warning sign on grocery store produce stand. Image credit:Moblog.
When a grape lands on the kitchen floor, I expect my Black Lab to scarf it down: like any other people-food item she beats me to. But, when it's a grape, she mouths it and spits it out. Now, I'm almost as smart as she is, having just learned from an article in Earthtimes, via PR Newswire, that grapes are fairly toxic to dogs. Read on for a list of common foods and decorative plants that frequently have toxic effects on pets.
The list comes from actuarial statistics of the Veterinary Pet Insurance Co., which reports that:-
Raisins and grapes topped the list, followed by mushrooms and marijuana. In 2008, the average amount claimed for plant poisoning was $427.One sentence in the report got me thinking about the possibility that pesticide residue rather than an intrinsic component of grapes may be involved.
Top Plant Poisoning Claims of 2008
7. Sago Palm
8. Macadamia Nuts
The exact cause is unknown, but some experts think that there may be a toxic component in the skin of the grape/raisin.Snopes reports that the grape toxicity issue is real for dogs; and Spopes also offers an unscientific sounding claim that pesticide residues are not a contributing factor. The amount of grapes or raisins that must be consumed to lead to a toxic effect on dogs also seems not well understood. Some accounts say "a handful," others that a dog must eat a pound or more. In other words, there is still reason to be skeptical about actual causation.
Perhaps someone has done a serious literature review to look into the grape toxicity dose/response question, and will share the findings with us?
I'm betting that most of the pot toxicity reports have something to do with brownies.
The article also points out that dogs like to eat fertilizer. Because pesticides are often blended with fertilizers, that can lead to a serious poisoning. One wonders how much of the exposure is due to actual direct consumption and how much is due to the animal simply walking on the treated lawn and then licking their paws clean.
Mushroom ingestion is listed as the second most common cause of poisoning in the insurance claims records. It's not totally clear as to whether certain domestically sold mushroom varieties are toxic to pets, and others not, or whether it is only particular wild mushroom genera that are associated with toxicity in pets. In other words, the true nature of the mushroom hazard for pets seems poorly understood (or at least poorly comunicated), which is likely to lead to some more urban legends. (I have watched my Lab sniff wild mushrooms in the yard and then back away and snort. She especially disdains Amanita muscaria, which can be quite toxic to people.)
Amanita muscaria. Image credit:EppingForestDC
It would most interesting to see if there is any propensity of particular breeds to eat the toxic items and of other breeds to not eat them.
Who knew that onions, even cooked onions, were very toxic to both cats and dogs? That too was a surprise.
Perhaps there is a behavioral reinforcement aspect to the overall issue: e.g. dogs want what they observe people to be handling and eating? Makes sense to me because dogs are pack oriented and instinctively expect an alpha animal (the owner) to share. (Whenever I go out to split firewood, my dog will grab a small log and chew on it.)