Holistic pet food would consist of quality ingredients fit for human consumption. If you wouldn't eat it, don't feed it to your pets! There should be no toxic chemicals such as MSG and other unfamiliar names that do not sound like food in your holistic pet food.
Also, gluten seems to be a big problem not only for humans, but for their pets as well. Actually, any grain has the potential to irritate your pet's digestive system. Many grains become contaminated with aflatoxins that grow on grains under the wrong storage conditions.
However, some organic grains like rice may be acceptable to your pet's digestive system.
I've heard some horror stories about what may be in commercial pet food - like road kill and euthanized pets along with their flea collars.
Does that sound like holistic pet food?
The pet food industry is highly unregulated and I would thoroughly investigate any pet food company before purchasing their food. I know it's a hassle to check labels, but it is so important to the well being of your pet's health to know what lurks in their pet food!
Shop around and ask a lot of questions about the ingredients used in pet food that you may be purchasing for your pets. I would think that the smaller pet food producers would come up with the best holistic pet food.
There is even such a thing as dehydrated dog food that may offer more nutrition for your pets than regular commercial dry food. Also, these days you will find in the refrigerated section of the larger pet stores - raw foods for your pets!
You want to see "real" foods listed on pet food labels as much as possible to help give your pets some sort of decent nutrition. Otherwise, they will become malnourished and start having food allergies that will make them miserable.
People love their pets almost as much as they love their own children. Yet when it comes to feeding their pets, they some how have been convinced that nutrition doesn't really matter to a pet.
If they only knew how much happier and how much healthier their pets would be - this attitude would change. Educate yourself about the "real" nutritional needs of your pets and dig deeper to find the answers. And look into making some of your pet's food as well.
I think that a lot of needless suffering can be avoided (for you and your pets) by feeding them a much more holistic pet food that is truly wholesome.