My dog has to be leashed each morning to prevent her from eating our cat’s food.
Consider malnutrition. It can be caused by three things individually or in concert with each other in all potential combinations.
By definition, malnutrition is lack of proper nutrition, caused by not having enough to eat, not eating enough of the right things or being unable to use the food that one does eat.
All animals and people are generally resilient enough that we can eat very poor diets not intended for us for limited periods of time. We’ll be OK, but not great. I won’t pick on the fast food giants here because there are a number of sociological constructs there for which 600 words just won’t do service.
But take the cannoli, a Sicilian dessert that is essentially a deep-fried sweet cookie wrapped around a decadent filling made with ricotta cheese, sugar and bits of chocolate. Most people would enjoy something like that until that was all they had to eat, as much as you want, for say, for 30 days. Or, if for the same 30 days, you were restricted to only one cannoli and water per day.
Finally, what if the cannoli provided for this situation were indigestible? Then you could eat all you want and get no nutritional value. While someone may survive these hypothetical situations, they would certainly be malnourished if not dead.
The same goes for most animals. They can eat a different ration of unintended feeds for a short period of time. If the ration is close to what they may eat but lacks a few essential elements or the ratio of each of the ration components are off, they may last a while but develop long-term consequences.
So back to dogs and cats. Yes, a cat, essentially an obligate carnivore, can eat some dog food for a while and be OK. But they can’t be maintained on that diet and vice versa. The reason is cat and dog foods are formulated differently by design to meet each species nutritional requirements. Think back to the definition of malnutrition.
Cat rations are formulated for carnivores, meaning animal-based meats, and animal fats in the right proportions are ideal. The protein level in cat foods is much higher than what is ideal for dog food rations.
Dogs are considered omnivores, despite what the wolf-becomes-chihuahua TV ads say. They can digest a wide range of appropriate ration components and do just fine. And while some dog foods offer 18-26% protein rations, do not try and keep a cat on that for very long or it will be malnourished. Most cats hate dog food anyway.
Dogs will run through fire to get to cat food because of its high protein content and the high level of fats. If you want to see diarrhea, feed your dog cat food without limits. They can’t handle that level of fats and protein and despite their zeal to get at it, they do not need it.
That leads us to desire. Just because a dog runs to another animal’s feed or feces does not mean it “needs” something in those any more than a person who chooses to eat their 20th cannoli at a dinner party does. An expressed desire does not a need make.
Finally, consider life stage of the animals. The nutritional needs in dogs and cats dictates ration formulations over three periods of time: juvenile growth, adult maintenance and all stages. It is important to select for the your pet accordingly.
Powell is the public information officer for the Washington State University College of Veterinary Medicine, which provides this column as a community service.
