The danger of grapes - a rumination

[chris-md]

To start I'm NOT claiming grapes are dangerous. I did, however, just put two and two together in a puzzle that I now lay at your feet for discussion:

Vets always say never give your dog grapes, they have acetaminophen.

A several months ago I had to admit Parker to the vet because he got ahold of an excedrine tablet, one main ingredient of which is acetaminophen. During this process I learned just 4mg acetaminophen is toxic.

I ask you: if grapes are so bad for dogs, why don't we hear more about the potential dangers of grapes for parrots?

 

[Flboy]

From what I understand, the issue with grapes/dogs is iron! Grapes and raisins are very high in iron!

 

[Rival_of_the_Rickeybird]

Wow. All I can contribute is that I think that the Rickeybird has had grapes now and then for most of his life.

 

[Scott]

I've heard grapes/raisins are dangerous to cats and dogs, but the mechanism is not fully understood. Never heard such caution for birds beyond pesticide concerns. Many of mine love very well rinsed grapes from trusted sources.

First I've heard of naturally occurring Acetaminophen.

 

[wrench13]

Wish some one with some authority would weigh in on this, Salty gets a few grapes once a week.

 

[chris-md]

Well this is interesting. Scott's post made me dig a little bit. Not one reference to acetaminophen.

This is strange. I've had a couple sources in my years reference acetaminophen in grapes, including a vet tech. So is it there or isn't it? Unfortunately any attempt at Googling acetaminophen and grapes wants to provide me with endless pages of children's grape flavored Tylenol.

Who knows??

 

[Loko]

Like others have said, the exact mechanism is unknown, but it is specific to dogs and cats (as far as I know). I would assume the vet said that grapes contain APAP because grapes have properties that can be similar or compared to APAP (antiinfallmatory, renal failure, abdominal pain) when consumed by dogs (or APAP overdose in humans as well), but they do not actually contain actual APAP as that is a synthetic chemical as far as I know, so they probably just said that to simplify the explanation? It is weird a vet would draw such an obscure comparison though. Why it affects dogs and cats only is not known, and other animals are completely unaffected. If I had to guess, I would say that theres probably some compound in grapes that is toxic to dogs for whatever reason, possibly a fungus/mold or a lack of, or unique presence of a certain enzyme. It seems they are unable to digest them properly as well, which gives reason to the enzyme theory. I read somewhere that researches suspect a mytotoxin [fungus] but are not sure. Whatever the reason though, it does not seem to affect birds.. maybe theyre not reactive to whatever it is that affects dogs and cats or have a natural immunity to it. I feed Loco concord grapes all the time as do many others, if it were toxic to them it would be well established at this point.

 

[Kentuckienne]

I looked at this for a while online. Most of the articles I found were about raisins and grapes being toxic to dogs, and not all dogs. One article said maybe 30% of dogs were susceptible and that one case of a poisoned cat was known. The grapes cause damage to the lining of the tubes in the kidneys, leading to kidney failure. No one claimed to have any knowledge of what the toxic agent might be. One reference describes a dark material coating the vessel walls, maybe tannins. Most articles claim that "pesticides were ruled out" but I found very few scholarly articles and no study reports. Just anecdotal evidence, some from vets.

So perhaps the warning has been extended to birds on he assumption that what's bad for one pet might be bad for another, so better safe than sorry. Grapes contain a lot of fructose, so everybody likes them. I sure know many people, including us, who feed / fed grapes to parrots daily with no ill affects. Since the only reported problem was renal failure, accompanied by vomiting, maybe pay attention to the "output" and if no problem, maybe your bird is not susceptible to whatever toxic agent might be present.

 

[Loko]

Well this is interesting. Scott's post made me dig a little bit. Not one reference to acetaminophen.

This is strange. I've had a couple sources in my years reference acetaminophen in grapes, including a vet tech. So is it there or isn't it? Unfortunately any attempt at Googling acetaminophen and grapes wants to provide me with endless pages of children's grape flavored Tylenol.

Who knows??

That is strange, but like my other post said, maybe theyre just referencing APAP because the symptoms of APAP overdose in any mammal and grape poisoning in dogs is similar? There is definitely no APAP in grape, that would be like having v*agra in an orange.. both are man made in a lab.

 

[jiannotto9492]

The only thing I can see go wrong with grapes for birds that will result in an emergency is from the pesticides. Unfortunately there's not enough information on why grapes are poisonous to cats dogs. But with that being said parrots and us humans are far enough away from cats and dogs that grapes are not a problem for us or our feathered children.

 

[Scott]

The only thing I can see go wrong with grapes for birds that will result in an emergency is from the pesticides. Unfortunately there's not enough information on why grapes are poisonous to cats dogs. But with that being said parrots and us humans are far enough away from cats and dogs that grapes are not a problem for us or our feathered children.

Totally agree, therefore I am very careful to choose a trusted source (as good as that theory can be!) and soak thoroughly with many changes of water.

 

[jiannotto9492]

The only thing I can see go wrong with grapes for birds that will result in an emergency is from the pesticides. Unfortunately there's not enough information on why grapes are poisonous to cats dogs. But with that being said parrots and us humans are far enough away from cats and dogs that grapes are not a problem for us or our feathered children.

Totally agree, therefore I am very careful to choose a trusted source (as good as that theory can be!) and soak thoroughly with many changes of water.

Gotta be careful with organics too as they can have pesticides as well. That's why I soak everything and anything I feed that's from the produce section.

 

[Dinosrawr]

There was a post yeaaarrsss ago about this topic. I remember weighing in with the research I did. Most scientific articles indicate that it can be what the grapes are treated with prior to consumption that can make them dangerous, or possibly a mycotoxin that is present in the grape. Not all dogs/cats that ingest grapes or raisins experience kidney damage or failure, which makes isolating the cause exceptionally difficult. Parrots, however, have frugivorous tendencies. So their physiology has allowed them to adapt to any possible dangers consuming certain fruits might toss at them, though some species will experience hemochromatosis and as such learned to naturally avoid the fruits that might harm them.

 

[Billdore]

Does anyone use the 3-1 water vinegar mix to rinse off the veggies? How long do you recommend soaking the veggies for before using? My Parrot Timneh loves grapes. I buy organic grapes only and usually just run them under warm - hot water for about 30 seconds. I just do 1 at a time. I feel like a darn fool now just cause I got organic.

 

[svheartsdesire]

Oh My....Ivan has had grapes every day for years (4)..all his vet visits have been good...it's also the only fruit he really enjoys...

 

[Teddscau]

I've read the same as Loko concerning mycotoxin. It was in regards to meerkats at a zoo rolling their grapes in clay before eating them. Clay is used in naturopathy to make poisons and toxins inert. The purpose of ingestion of soil and minerals in wild parrots is believed by many researchers to nullify the many toxins in the seeds and nuts which comprise the majority of a parrot's diet. Plants try to deter predation of their unripe seeds and nuts by using some sort of physical deterrent (hard shell, spikes) or chemical deterrent (caustic, toxic, or bitterness). When their seeds or nuts are ripe, many plants encourage animals to eat their seeds so they'll spread them in their feces by offering fragrant, sweet, colourful fruit, or by losing or weakening the physical or chemical defences that they were using to protect the unripe seeds. Parrots feed on unripe seeds and nuts, using their powerful beaks to crush the hardest of shells (i.e., macaws, cockatoos), and are able to withstand the toxins in the unripe seeds/protective outer flesh that would cause other animals to become violently ill or leave them with chemical burns. Obviously I'm not suggesting to give captive birds such foods, as they don't have access to the same nullifying compounds that wild parrots have access to.

Same as Dinosrawr was saying. Plus, you've gotta remember that parrots can eat the hottest of peppers without getting gut rot, further supporting not just the use of detoxifying and nullifying compounds, but also physiology.

Hey, Billdore, as far as pesticide concerns go, I'd start buying from health food stores. At my local one at least, all their produce is certified organic, so you don't have to worry about transference.

 

[GaleriaGila]

Thanks for that!
Fascinating.

 

[BeatriceC]

Wish some one with some authority would weigh in on this, Salty gets a few grapes once a week.

MrC is a PhD level biophysicist and worked in pharmaceutical research until he retired. I just asked him to look it up for me.

 

[GaleriaGila]

Now THAT's COMMUNITY!!!!!!!!!!!!!!!!!!!
Thanks in advance, Mr. C!!!!!!!!!!!!!!!!!!!

 

[chris-md]

Hot damn! ,can't wait to see what MrC finds. Fascinating discussion even if likely started under incorrect assumptions