Can a dog's digestive system "change"?

Discuss ways to improve the quality of your dog's life and longevity through proper nutrition; a place for all of your questions and answers about feeding your pooch!

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Barked: Fri Feb 10, '12 8:27pm PST 
Oakley has been having diarrhea for the past few days, and I was finally able to get him a vet appointment this morning. He's been eating/drinking/playing normally, hasn't gotten into anything inside or outside, or done anything that would concern me. He's been eating Orijen puppy food since probably 9 weeks of age, and he's currently almost 15 weeks. He's had absolutely no problems with the food.

At the vet this morning, they performed a fecal smear to analyze bacteria, and he did have more than he should have. The vet narrowed it down to either intestinal parasites (I'm taking a fecal sample back in the morning for them to analyze), something he shouldn't have eaten, or his food. He asked what Oakley was being fed, and I told him. He said that the "premium" food like Orijen and Taste of the Wild have been known to cause diarrhea, and that there was absolutely nothing wrong with feeding a dog grains. I said I understood but would be choosing not to feed him any, and stated that Oakley has been fine on this food. He then told me that as dog's grow and mature, their digestive systems "change". I'm assuming he was implying that a dog's system could grow to not tolerate a certain food anymore.

Is this possible or does this even make sense? I don't understand how my puppy could be doing fine on this food for six weeks, and then suddenly have a problem with it. Granted, it could very well not be the food at all but I'm just curious if anyone else has had this problem before.
Jake Earned- his wings- 10.02.15

I am Murphy's- Law Embodied! <3- Me!
Barked: Sat Feb 11, '12 1:47am PST 
i don't know about 'changing' digestive systems but I do know that jake had some problems with dog food stemming from allergies. When i first got him i put him straight to avoderm and he was liquid out the other end so i switched him to Authority and he got firm for a minute then it started going south. Moved him to Blue Wilderness and again he was good for a few weeks the it went south. Finally tried TOTW and his horrific farts went away but still he pooped way too much and it was inconsistant. The only thing i've found to really work for jake is Raw feeding. But i know that's not for everyone.

So i guess it's possible for your dog to be okay on one food then suddenly not be able to tollerate it.

Semper Vorax
Barked: Sun Feb 12, '12 12:43pm PST 
well the intestines are an organ that can wear out. The cilia can be clogged or killed off by stuff the dog eats, muscles that move matter through can weaken or tear, bulges, polyps, allergies and intolerances can affect the way the system works, infammation can cause a change in performance, bacteria levels can change, infections can cause all sorts of problems, scar tissue, parasites, and even genetics.

Yeah even human GI changes over time. It's part of the aging process, and has to be adjusted for. You can't eat the same things you did when you were a kid, and it's a fair bet that dogs might have trouble as older adults with stuff that they ate as younger dogs.


Semper Vorax
Barked: Sun Feb 12, '12 11:26pm PST 
anyway, yeah, GI changes a alot between puppyhood and adulthood. They will no longer tolerate milk, for example. They need less fatty food between age 1 and 3. dogs are in that human equivalent age 15-25 at age 1-3. They need a good kind of nutrition as early adults that will set them up for life as older adults, but it's not the same a puppy diet.
Bruno CGC

Honorary Kelpie
Barked: Sun Feb 12, '12 11:39pm PST 
Taggert, the OP is fifteen WEEKS. He's still a baby- I understand that elderly dogs might begin to have trouble digesting certain foods, but a little puppy? That seems fishy. Sounds like the vet just doesn't like the brand of food she is feeding and will say anything to get her off it. (My take on the situation at least.)

Barked: Tue Feb 14, '12 4:00pm PST 
I know I can not eat some of the foods iused to eat 10 years ago. Now I have to be careful and watch what I eat. So yes I think it can change as we get older.
Hope, NPC- (In Loving- Memory)

Queen- of Naughty-
Barked: Mon Feb 20, '12 1:37pm PST 
Hi Oakley's mom,

Did you happen to start a new bag of Orijen right before the diarrhea started? Sometimes different (Orijen) lot numbers (found on the top of the bag) have a different combo of protein sources. HTH
Jo Jo

Barked: Thu Feb 23, '12 2:14pm PST 
Puppies have digestive systems that are much like babies. They do not come out of the womb fully formed and therefore their digestive systems develop as they age. I don't think that saying they "change" was really the best way to phrase this to you. Anyway, puppies do not come "built" with all the enzymes and/or probiotics and prebiotics that they need. So, often what will happen is that they will be doing just fine with a food and as their digestive system develops and they begin to break down more of their food, their little intestines realize they are lacking enzymes and begin trying to figure out what to do and in all that havoc, you get some loose stools or digestive upset. I would recommend adding enzymes to your dogs food. Now, you may also consider probiotics but the issue is that probiotics have to make it live to the intestine, which is easier in puppies than in adult dogs, but still not an easy thing to accomplish and especially not in the numbers necessary for you to see a change in loose stools. No matter what, puppies have probiotics in their digestive systems, it's just a matter of how many. It's a better idea to add an enzyme and prebiotic formula to your puppy's food (prebiotics being the "food" for the good bacteria (probiotics) of your puppy's digestive track) because that way you can just encourage those good bacteria to grow, without having to worry about something living through the stomach to the digestive track.

Here are some products I would recommend you try, from a company that has helped me with my younger dog, Jo Jo. They have a nutritionist on staff named Lindsay and she is immensely helpful, so you could also consider giving them a call and asking for her and seeing if she has some tips for you as well.

Digestive formula that Lindsay recommended for Jo Jo and I found worked far better than probiotic/enzyme formula I found. It's a blend of medicinal mushrooms that are prebiotics and worked wonders for my puppy.


Here is an enzyme formula that I have used for my senior dog Sam, that has seemed to help some as well:

http://www.republicofpaws.com/animal-essentials-enzymes-and -probiotics/

Hope this helps!
-Jo Jo
Kali earned- her wings- 10/21/14

She's game for- anything that's- fun.
Barked: Fri Feb 24, '12 6:09pm PST 
I believe their digestive tract can change. Kali ate the same food from a tiny puppy til she was a year old. All of a sudden, she couldn't have it anymore. She got severe diarrhea from it.