Science Says Dogs’ Digestive Systems Evolved with Humans

Eats dirt.

Eats dirt.

I know the “Dogs do not have the enzymes needed to digest grains!!!!!!!!!111!!!11″ camp had to be hatin’ this study which found that dogs’ digestive systems evolved over time to better allow them to digest starchy food.  Now there’s more bad news:  another study has found the same thing:

The team then compared corresponding genes in dogs and humans. They found both species underwent similar changes in genes responsible for digestion and metabolism, such as genes that code for cholesterol transport. Those changes could be due to a dramatic change in the proportion of animal versus plant-based foods that occurred in both at around the same time, the researchers said.

Basically, as humans evolved and their diet included more plants, so did dogs who were hanging around humans, eating their “table scraps”. I know this does not fit the “Your dog is a wolf” narrative that has gained such a vocal following among food wonks but there it is.

I don’t intend to advise anyone who is satisfied with their feeding plan to alter it.  If it works for you and your dog, paws up.  I do consider it ignorant bullying when people of the OhNozGrainz persuasion drop in on every food discussion thread they come across and decry the feeding choices of others with no acknowledgement of the emerging science. Please don’t engage in that type of behavior here.  (Not that this will slow anyone down, since they won’t even read it because they are too busy typing ALL GRAINS ALL BAD in the comments, but it seemed like a polite word of warning.)

Discussion: Dog Food Wonkery, Now With Added Science!

Talking about feeding starchy foods to dogs is one of those things that tends to stir up controversy.  So let me state up front that this post is going to discuss feeding starchy foods (potatoes, grains, etc.) to dogs and I am neither encouraging nor discouraging anyone from changing whatever they choose to feed their own dog, assuming they are satisfied with the results.

My experience with feeding my own dogs (your mileage may vary) is that they do well with starchy foods.  I like to take full advantage of this since it means less cost and less meat in their diet.  My thinking has been that my dogs probably seem to do so well with starches because they have adapted to a diet of human table scraps over the millennia.  I have never found any study suggesting this (until today!) but it seemed to make sense to me.

And now for a moment of science:

Fido may prefer steak, but his digestive system is also geared up for rice and potatoes. That’s the conclusion of a new study, which finds that dogs have evolved to eat a more varied diet than their wolf ancestors.

The link gets into the harder science, for those who are fond of single-nucleotide polymorphisms and such.  But suffice to say that this study suggests that as the domesticated dog evolved, he relied more on food humans threw away and less on live prey.  Dogs whose digestive systems evolved to make better use of starches, a primary human food scrap, were at an advantage over those whose systems did not adapt to this change from the wolf model.

Which brings me to a favorite fun thing:  sharing old dog food practices.  If someone would write a 50,000 page book on this, I would retire to a deserted island with it.  But for now, I am sharing a tidbit from Paddy Petch, author of The Complete Flatcoated Retriever (1988).  In the book, she states that she feeds her adult dogs three meals a day.  One meal is comprised of 1/3 meat (canned, fresh or dried), 2/3 biscuit or mixer meal (I believe this is basically a meat free type of kibble) and any scraps from the kitchen, including vegetables.  The other two meals are made up of milk plus regular kibble (which would be primarily starch) or cereals (just starch).  Her diet plan obviously involves a much lower amount of meat than many home prepared feeders give to their own dogs.  Again, not trying to influence anyone in their feeding choices, just sharing info.  Because it’s wonky and I like it.  A quote from Paddy Petch:

To my mind there is far too much nonsense talked about scientific feeding these days, and many dogs would benefit by going back to the good old fashioned ways of going on.

If you have thoughts on the linked study, Paddy Petch’s feeding regimen, or want to share some old dog food recipes (especially that!), please join in.

A Visit to the Emergency Vet and Why Billy is “Family Circus” Funny

Last night we took Graham to the emergency clinic for a suspected urinary tract infection.  She’d been having accidents in the house for about a week but last night was the first time we saw blood in the urine.  So we decided to take her in to get her started on antibiotics last night instead of waiting until after work today.  She’s doing fine (she didn’t see the estimate we were given for ultrasound, x-rays, blood panel, urinalysis, etc. so of course she’s fine) and got her first dose of antibiotics last night.

It’s always awkward visiting the emergency vet since you don’t know them and they don’t know you.  Routine questions like, “What does she eat?” can get weird.  Sometimes I wonder if I should just lie and name a popular brand of kibble.  That would be one way to guarantee a hassle free visit.  But I braced myself and answered, “Homemade food”.  The technician then asked, “Is it people food or some type of dog food?”

Well you got me there.  Is it people food?  Dog food?  I hesitated for a moment and the technician chimed in with, “Believe me, I’m not going to judge”.  M’kaaay.  I replied that it was a high protein, moderate carbohydrate diet with added calcium and essential fatty acids.  I thought that was a clever way to avoid the question while providing an answer that demonstrated I wasn’t some dummy feeding my dog moon pies and gum – you know, to reassure the technician that everything was going to be all right, even though I was feeding my dog homemade food of unspecified people/dog origin.

The technician dutifully wrote my answer down on the record then looked up and judged.  She said she was concerned about the high protein, considering Graham’s age (she’s 12).  Billy spoke up at that point, joking that the dogs eat better than he does.  He probably thought this would lighten the moment and prevent me from going into food wonk mode.  The technician didn’t laugh.  But mercifully she shrugged the whole issue off with, “Well if she’s not having any problems, I guess…”  Whew.  Crazy dog lady fit averted.

After the technician left the exam room, I of course turned to Billy, my captive audience for the inevitable protein requirements of senior cancer dogs diatribe that was bubbling inside me.  Because he thinks he’s funny, and because he’s suffered through one too many such diatribes, Billy tried to cut me off with, “I agree with her.”

Isn’t he just a laugh-riot?

Dinner at Chez Dog

For Christmas dinner, I made the dogs chicken noodle soup using some leftover yellow squash and baby carrots, egg noodles and of course, chicken.  After I snapped this photo, I topped the dish with some chopped hard-boiled egg.

Mmm mmm good!

Food for Sharing

Digital camera archives:  I found some pix of food I’ve made for the dogs which is great for sharing with humans.  I’m happy to post recipes (if I remember how I made any of these things, lawl) upon request.



Dog Food Wonkery: Grains

There are various arguments against the inclusion of grain in the canine diet.  One is that grains cause allergies in dogs.  This article offers the perspective that the incidence of grain allergies in dogs is extremely low.  Another common argument against feeding grains is that the dog has no dietary requirement for carbohydrates and would not encounter grains (except for very small amounts in the stomachs of prey animals) in the wild.  This is true but also raises more complex issues.  For example, dogs were likely domesticated partly because they could adapt to the diet of humans (omnivores) and thrive off humans’ “table scraps”.  Over time, the domesticated dog evolved differently from wild canids and, even though the genetic differences may be small, I think it’s a legitimate question as to whether we should model our pets’ diets after their wild counterparts.  In other words, I am not feeding a wolf, I’m feeding a domesticated dog who evolved separately and with slight genetic variations from wolves.  So why should I strive to feed my dog the same type of food a wolf eats?  Further, every dog is an individual and the specific needs of the individual obviously outweigh any textbook definitions of “natural diet”.  If your dog can not tolerate X as part of his diet, that’s the end of the discussion on X for your dog’s diet.

A further complicating issue for many pet owners who are concerned, for environmental, ethical and/or economic reasons, with minimizing the amount of animal products they purchase, is whether non-animal food sources, such as grains, can be safely fed to dogs.  That is, can some (or all, in the case of those feeding vegan diets) of the animal-based food sources in the dog diet be replaced with non-animal ingredients which can be digested and utilized by the pet?

In looking at these questions, I think it’s important to remember the basics:  Grains=Carbohydrates=Energy.  (Note:  The issue of grains as a source of protein for dogs is beyond the scope of this short post.)  Energy is required by all living things.  Dogs can get energy from more than one food source:

If the dog’s energy requirement is not supplied by a carbohydrate or fat source, the energy deficit will be met by the metabolism of protein. Although the dog does not have a specific dietary carbohydrate requirement, carbohydrates are usually its principal source of calories.

Of the grains I currently feed to my dogs, rice is by far the most common.  Cooked rice is highly digestible and well utilized by dogs (although historically with my dogs, white rice is well digested whereas brown rice is not).  I want to feed the amount of animal products necessary for my dogs to thrive and I want to make use of non-animal ingredients which they are capable of utilizing for the remainder of the diet.  Rice works well for my purposes.

Do you include grains in your dog’s diet?  Why or why not?  For those who do include grains, what type do you use and what percentage of the total diet do grains represent?

 

 


Dinner at Chez Dog

Lately I’ve been making what Billy calls goulash.  I boil chicken in an oversized pot with extra water.  About halfway through, I sprinkle in a small amount of rice and add chopped veggies.  Today’s veggies were sweet potatoes, celery and carrots.  By the time the chicken is done, the rice and veggies are cooked and there is still yummy broth in the pot.  After cooking, I stir in some minced greens (kale and celery leaves were what I had on hand today).

It’s a perfect dish for cold weather and can be served on its own or as a kibble dress-up.

Dinner at Chez Dog

Pancakes:
2 Cups whole wheat flour
4 eggs
2 Cups milk
generous sprinkling of cinnamon

Whisk all ingredients to make a batter and set aside while you make the filling.

Filling:
Heaping Cup ricotta cheese
2 hard boiled eggs, peeled
2 bananas
Heaping Cup cooked rice

Put first 3 ingredients into a food processor and mix until smooth.  Stir in rice.

To make the pancakes, pour them out thinly into a medium-hot, greased frying pan.  After they are cooked, allow them to cool to room temperature.

Spread the filling over each pancake and roll up.  Slice into portion sizes suitable for your dog.

Recipe adapted from one found in Cooking For Your Dog by Ingeborg Pils

Food Wonks, Gather ‘Round

Reducing fat and calories can lower cancer risks for dogs (and people!) according to newly presented research.  Specific recommendations including lowering dietary intake of sugar and Omega-6 fatty acids (e.g. nuts, seeds, corn oil, soybean oil and grain-fed red meat).  It’s important to note that Omega-6 fatty acids are not “bad”, it’s just that they are commonly out of balance with Omega-3 fatty acids in the American diet.

There’s another interesting tidbit in the article on fiber:

[T]he ideal blend of fiber for dog food is about 75 to 80 percent insoluble and 20 to 25 percent soluble.

Examples of insoluble fiber (the 75% recommendation) are whole-wheat flour, wheat bran, whole-grain breads/cereals, nuts, seeds, brown rice and many vegetables.  Food sources for soluble fiber (the 25% recommendation) include oats, oat and rice brans, peas, beans, apples, citrus fruits, carrots, barley and psyllium.

To put this in some perspective with regard to dog diets, that National Research Council’s 2006 pamphlet (pdf) on canine nutrition says:

Q: How much fiber is good for my dog?
A: Fiber in the diet is probably good for overall gastrointestinal health and may help some dogs keep their weight down. The typical diet of normal adult dogs contains between 2.5 and 4.5% fiber.  However, the fiber content of some “diet” dog foods may be higher. This may allow the dog to feel full without consuming too many calories for effective weight control.  Diets high in fiber also may help in the management of hyperglycemia (high blood sugar), and may improve large intestine function.

On the other hand, too much fiber in the diet can decrease the digestibility of other important nutrients and result in loose stools, frequent defecation, and reduced palatability of the dog food. Wheat bran and barley products are high in fiber.  Conversely, dog food ingredients high in starch, including rice and dried potatoes, have less fiber.

Dinner at Chez Dog

Leftover bits from the produce drawer that I needed to use up before they went off:  spinach leaves, broccoli, grape tomatoes.  Add rice, chicken livers and turkey thighs and dinner is served.

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