what is in commercial food that my cats cant tolerate?

My 80 year old mother ended up with 10 Bengal/Siamese mixed cats, all related...long story on that one.  Anyway, they all seem to have some sort of digestive issue, that's made it impossible to find them homes.  They have tested fine at the vets.  Poops been checked, nothing found.  When I first got to my mothers all of them had horrific diarrhea.  I took them immediately off of cheap dry food and tried top of the line, no grain dry food, and they stopped pooping their pants...so to speak. But still had horrible diarrhea and vomiting.  But they were playful, affectionate and very energetic-very weird.  I have spent 2 years painstakingly trying every commercial food I could find and every protein source available .  They are not allowed to eat dry food anymore, of any kind.  The only canned food they could sort of tolerate was an all beef and liver 95% protein one that is pretty expensive, but they still  had lose stools and a few still vomited almost daily.  I was about to just buy mice and let them have at it.  Anyway, I started making their food. I do cook it since it's just too hard to feed that many cats raw food. Just too chancy for the humans. The thing is they are tolerating the ground beef, bone broth, egg(with shell), liver and supplement concoction I make for them just fine.  They used to take their time eating the canned food and I'd end up throwing it away,.  They gobble the stuff I make for them.

So, what is in commercial food that they can't tolerate?  Could it be a preservative? 

I know lots of people have conflicting ideas on how to make cat food, and many feel that canned food is balanced for what cats need, but it was making my cats sick.What I am feeding them may not be perfect, but there has been a big improvement.  I'm going to try and start adding a little turkey and chicken to see if they can tolerate it.  I'm still looking for the best supplement to make up for not getting bones in their diet and whatever else. Probiotics don't seem to do anything , except make them turn their noses up at their food when it's mixed in, but I'd like to find one they will actually eat. 

If anyone has any idea what is in commercial cats food that could be making my cats sick - I'd love some ideas. 

Thanks

Curious as to how you came up with your homecooked diet. Did you find a recipie online or in a cat nutrition book? You may want to look into a pre-mix for your homemade food just to be sure that the cats are getting all the nutrients they need. I know there are some that are specifically for plain cooked meat. One is U-Stew, knowbetterpetfood.com and the other is Fresh + Oasis Feline T, completenaturalnutrition.com

Catinfo.org may have the answer you are looking for about commerical foods. I know that some brands are full of preservatives, cheap fillers, and other things that some cats may be sensitive to.

I spent months reading up on how to make them food and every website, vet, cat person seemed to say something different.  And they are all quite aggressive on being right - very confusing.  I'm still experimenting.  I have added a supplement made for cats.    It also seemed that a lot of sites were pushing a supplement.  I'm trying to add the things that everyone agreed on.  Few thought beef was a good idea, but I know it's something they can tolerate.  Everyone agreed on bone broth.  That is a 42 hour process, but worth it. 

I was feeding them very high quality canned food, but it still made them sick.  

Thanks for the websites, I will check them out.  

I'm sorry I have no advice to give, I just wanted to say you are a hero for taking care of 10 cats!  And with such upset tummies, poor kitties.  How difficult it must have been for you.  If they're tolerating your home-cooked food so well and getting all the nutrition they need, so good for now.

That is one of them in your avatar picture?  Beautiful looking cat. 

It could be the bengal breed in them.  I have no personal experience but I have read that bengals, even the ones that are 5th generation with just a tiny bit of the Asian Leopard cat in them often don't do well on commercial food.  Maybe they need to be closer to the simple uncomplicated diet that they would get in the wild.

Have you ever had any of their stool cultured for pathogens?  I am not an expert in this field but I have read a lot on here about various bad bacteria causing problems, and once identified, they can be eradicated.  It may be combination of being intolerant of food and something else.  Saccharomyces boulardii is a yeast based probiotic which seems to be doing wonders for clearing up chronic diarrhea in cats and humans too.  Google it and read about it.  There is also a thread here that @LDG posted for our members and their vets that includes links to a lot of articles about this.  Here is a link to that thread:  http://www.thecatsite.com/t/283161/saccharomyces-boulardii-use-for-diarrhea-and-gi-disease-incl-ibd

I'm going to try the S. boulardii myself on one cat who has had chronic diarrhea since he was a kitten, but I have no experience with it yet.  It certainly can't hurt.  If I were you, I would look into this and read some of the threads about it.  You have enough cats you could try it on some and not others as a test and control situation.  One thing I read in one thread is that the Jarrow brand is bitter, but the NOW Foods one (I think) was not and they ate it in their food, so DON'T buy the Jarrow brand.  Fine for humans, who swallow pills, but not for cats.  Prices vary but in general it is not expensive especially if you get it online.  I'm not sure if it is more in health food stores.

What kind of water are you providing? Try bottled and see if that makes a difference.  (bottled with cooking)

A recent study in humans showed that what was considered "food allergies" turned out to be something in the tap water that was being used to cook the food.

http://abcnews.go.com/blogs/health/2012/12/03/pesticides-in-tap-water-linked-to-food-allergies/

We have well water, they drink the same water they do.  We did have 2 of the cats stool checked and nothing showed up. The reason I'm pretty sure it's a food intolerance is the cats that aren't related don't have any digestive issues.  Since I've been making their food, their bellies seem to be doing better, and poops no longer smell horrible.  I am giving them probiotics, don't know how much that is helping, but worth a try. 

My cats had problems on commercial canned food.  Gadget had diarrhea the worst, but Mason and Julie had it as well.  What's weird is Mason and Julie are related, but what bothered Mason didn't always bother Julie, and vice versa.  The poop was clean at the vets, we wormed and medicated to no avail.  Finally I tried raw and they were noticeably better in 24 hours.  If home-cooked is what helped your cats and it is a balanced diet, good for you.

My cat had vomit issues that improved a great deal when I stopped letting her out, took away dry, and switched to grain free wellness CORE chicken,turkey,chicken liver wet or Merricks Duck pate wet. I also give vets best hairball relief digestive aid (has slippery elm) am and pm.