Study: Starch Digestion Adaptation in Dogs

[release the hounds]

Originally Posted by PWCorgi

Can't say I've ever had that issue. My dog's diet is about 5% veggies and if they're broken down correctly they aren't going to show in the poop. If I feed him a whole carrot, yeah he craps orange, but the veggies that have been cut down through a processor seem to digest just fine.

mine are blended down as well. I rarely feed them though, maybe once every 2-3 weeks

[Southpaw]

Originally Posted by Pops2

Just because they CAN digest a lot more starch doesn't mean they SHOULD.

Like.

I mean, I don't feed a starch-free diet anyway but this doesn't really change my opinion on how I'd prefer to feed them or what I think is best. And I guess I never really had the viewpoint that they CAN'T have these things - just that they don't NEED them.

But what do I know, I'm not sure I even know what I just said.

[~Jessie~]

Originally Posted by Lyzelle

In a way, I'm not surprised, but in another I'm not really sure what this is supposed to change anyway. Humans have no species-specific diet, but there are a lot of things we *can* digest that aren't necessarily good for us, such as grains and starches. In no way does this mean dogs should have a diet high in starch or carbs, but it's the same as it has always been. Feed your dog according to it's own personal needs. Some dogs, some breeds, are slightly different than others when it comes to nutrition. Siberian Huskies typically do better on fish, for example. That was their diet for a couple thousand years, so it's natural that their bodies would have optimized in order to get the most out of that diet. And some cons, too, such as being more sensitive to a diet lacking copper and zinc, since the diet they became acclimated to was so high in it. Really no different from some humans who can tolerate cow milk(unnatural to humans), but most can't. How some people handle carbs or grains better than others.

So, in the big picture, I really don't think it has changed anything at all. Amylase is still a protein that turns starch into sugar, and then maltase breaks it down into a more simple sugar. Sugar carries little to no nutritional benefit at all, and these proteins aren't extracting any nutritional benefit from it. No minerals, no vitamins. If anything, sugar is converted to fat, and the dog's body would simply then burn the usable stand-by body fat in lean times, while still starving on a molecular level from the lack of nutrients. Common enough for a scavenger.

In no way would I see "oh, they can digest this, so they must NEED IT". I mean, scavengers can also digest rotting, vile meat. Do you think there's any nutritional value or need to feed your dog rotting meat? Probably not. They can have it, but it's not like it's any better for them to have it over fresh meat.

So I guess I really don't see how anything has changed at all, except maybe proving it, I guess.

Yeah, this.

[AdrianneIsabel]

Sloan can't stomach barley. Clearly this is false. (I'm teasing)

[sassafras]

But having some sort of science to back it up IS the whole point. Right now SO many things about nutrition are nothing more than opinion. Now there is actually some evidence that dogs have evolved this ability to digest starches.

The idea of whether they "should" or not is still a matter of opinion, I think. And I'm certainly not saying WHEAT GLUTEN FOR EVERYONE!!!!11!! but at least it gives a factual basis for whether it's ok to include some grains/starches in a balanced diet... and even more exciting to me, validates the idea that there are real, measurable genetic differences here. Maybe some day we can say with more certainty what an individual dog "should" or "shouldn't" be eating.



ETA: We already know there is tremendous individual variation in things like... drug receptors. That's why ibuprofen works great for one person and hardly works at all for another person, or why morphine makes one person sick and is an awesome pain reliever for another person. Having a measurable way to demonstrate that things like that are true for digestion... it's just exciting to me to see a possible future where the clamor of diet extremists is quieted by real evidence that digestion and suitable diet may be genetically different from one dog to another, so there is no "one true way" and plenty of room for a variety of ways to feed individual dogs.

[Shai]

Originally Posted by sassafras

But having some sort of science to back it up IS the whole point. Right now SO many things about nutrition are nothing more than opinion. Now there is actually some evidence that dogs have evolved this ability to digest starches.

The idea of whether they "should" or not is still a matter of opinion, I think. And I'm certainly not saying WHEAT GLUTEN FOR EVERYONE!!!!11!! but at least it gives a factual basis for whether it's ok to include some grains/starches in a balanced diet... and even more exciting to me, validates the idea that there are real, measurable genetic differences here. Maybe some day we can say with more certainty what an individual dog "should" or "shouldn't" be eating.



ETA: We already know there is tremendous individual variation in things like... drug receptors. That's why ibuprofen works great for one person and hardly works at all for another person, or why morphine makes one person sick and is an awesome pain reliever for another person. Having a measurable way to demonstrate that things like that are true for digestion... it's just exciting to me to see a possible future where the clamor of diet extremists is quieted by real evidence that digestion and suitable diet may be genetically different from one dog to another, so there is no "one true way" and plenty of room for a variety of ways to feed individual dogs.

^'Zactly

Also...
/me is a morphine-puker. Very sad. Finding this out post-surgery was even more sad.

[Beanie]

Originally Posted by Pops2

IF you believe in evolution, there is pretty good evidence they evolved from a common ancestor rather than directly from wolves.

Yes, scientifically speaking that is absolutely the case. Dogs did not evolve from wolves, they just share a common ancestor.
So Mitochondrial Wolfdog evolved down into both wolf and dog - two separate evolution paths. Not the same as "evolved from wolves."


I think what it changes is people who argue that dogs are exactly the same as wolves and therefore should eat the same as wolves. There's a genetic DIGESTIVE difference; here's proof that they just flat out are not the same. (Of course arguing genetics with some of these people still doesn't mean that they recognize the scientific difference.)

A coyote will certainly eat corn and we know from scatology studies they can digest it (though how well is another argument.) Does that mean they SHOULD eat corn? That corn is somehow part of a "balanced" and healthy diet? Does that mean they wouldn't rather pick a tasty, tasty rabbit over corn? No, none of these are necessarily true, and I believe that holds true here as well.
It's just a matter of a genetic difference between dogs and wolves. I think it makes sense, as is pointed out in the article: a critter who can better digest grain would thrive in a rapidly agriculturalizing, grain-producing society over a critter who can't digest grain. (And once again to the coyote comparison - they're certainly doing well around us, so well they're moving IN to towns in places...) Survival of the fittest and all that. So obviously that critter would thrive and produce offspring and eventually evolve into modern day dog. It's been argued for a long time that people used to just feed their dogs whatever they had as leftovers - which was not necessarily meat - so this is all in line.

It's fascinating to me genetically/biologically, not so much from a dietary standpoint.

[StillandSilent]

Corn makes my coyote fart. Clearly it is the ebil!

I have seen him stripping kernals right off the ear, though, so he must like the taste. Incidentally, this is how I know that it makes him fart.

[SaraB]

Originally Posted by sassafras

But having some sort of science to back it up IS the whole point. Right now SO many things about nutrition are nothing more than opinion. Now there is actually some evidence that dogs have evolved this ability to digest starches.

The idea of whether they "should" or not is still a matter of opinion, I think. And I'm certainly not saying WHEAT GLUTEN FOR EVERYONE!!!!11!! but at least it gives a factual basis for whether it's ok to include some grains/starches in a balanced diet... and even more exciting to me, validates the idea that there are real, measurable genetic differences here. Maybe some day we can say with more certainty what an individual dog "should" or "shouldn't" be eating.



ETA: We already know there is tremendous individual variation in things like... drug receptors. That's why ibuprofen works great for one person and hardly works at all for another person, or why morphine makes one person sick and is an awesome pain reliever for another person. Having a measurable way to demonstrate that things like that are true for digestion... it's just exciting to me to see a possible future where the clamor of diet extremists is quieted by real evidence that digestion and suitable diet may be genetically different from one dog to another, so there is no "one true way" and plenty of room for a variety of ways to feed individual dogs.

This.

On a separate note, I've always been the believer that a well-varied diet is best when creating a diet yourself (ie raw feeders). I don't have vitamins to add, I don't measure everything out, but I rely on the same principle I rely on when I feed myself. Variety is key. So when I choose protein sources, organs or add-ins for my dog's diet I go for the largest variety I can to ensure that I'm providing as balanced of a diet as possible. All this study shows me is that by having the ability to digest these things, that they are actually getting something from them. All this does is confirm that I have another venue to add even more variety to my dog's diet whether it turns out to be just sugars or some vitamins they are lacking.

So yes, I am going to be one of those people that adds more veggies/starches whatever into their dog's diet based on this article. It won't hurt them so why not?

[Psyfalcon]

28 times 0 is still 0. 28 times terrible might still be terrible. You can see the difference between say, raw, and a corn first dog food on the other end.

Still, it is pretty interesting that dogs changed that fast. Functionally, I'd consider the wolves they split from fairly modern. Morphology is pretty close, at least within the variation in the species now.