Dogs & Cats are CARNIVORES. Feed them RAW DIETS.
I'm going to shoot it to you straight from the heart. I have been a veterinarian for 17 years. I went to the College of Veterinary Medicine at the University of Tennessee at Knoxville where I graduated in 2001. All throughout that time we were offered small amounts of education in nutrition.
We were, however, offered very large amounts of free food and pizza parties from sponsors such as Purina, Eukanuba and Science Diet. ALL of our pets received free food from these companies for four years. And I am NOT complaining! In debt up to my hair follicles, I was thankful for the food, the pizza, and snacks they provided.
I continued that path of feeding those types of foods for many years. I had an epiphany sometime in 2012 when entertaining the simplest thought. You know how when something so simple is presented to you and it makes you feel so dumb? That's what happened to me!
Then it occurred to me that cats are obligate carnivores and dogs are scavenger carnivores. They each have carnivorous shearing and stabbing teeth. They also have the shorter length gastrointestinal tract which carnivores need. Not to mention having a highly acidic stomach pH to kill pathogens from raw meat! (Insert light bulb) THEY ARE CARNIVORES! They NEED meat. Protein is life, but not just any protein. They crave muscle meat, organ meat - the good stuff.
Your dog and cat need a species appropriate diet to produce energy to grow correctly, maintain health during adulthood, and live to enjoy a quality old age. The list of ailments that dogs incur from not eating a species appropriate diet is extensive. Dogs simply will not thrive without it. They can have poor immune systems, odd behaviors, chronic skin and/or ear issues, obesity, and so much more.
All kibble has starches and carbohydrates in them to hold them together. You may remember from somewhere back in elementary school that proteins are made of amino acids. When they are heated, they are partially destroyed. All dry and canned commercial dog and cat food is heated in the manufacturing process. So already deficient food is made even more deficient from the process used to make it.