Dexter's diet has changed quite a bit from his wild ancestors, moving from what he was able to forage for himself to, in many cases, kibble from a bag. As vets and researchers learn more about Dexter's past, many commercially prepared foods are manufactured with his wild heritage in mind.
Dexter's Wild Roots
Though he may not look like it, Dexter's forefather is the timber wolf, from whom he -- and his pals from the dog park -- evolved from about 15,000 years ago. Like his wolf ancestors, your pup needs meat, needing the nutrients only animal-based proteins can provide. He's built for eating and digesting meat. However, a healthy, natural diet for Dexter needs requires than meat, meaning he's more than a carnivore -- he's an omnivore.
Dexter's Nutritional Requirements
If you're a vegetarian and aren't keen on Dexter eating other creatures, you should give him a pass. A dog requires animal-based proteins to meet his important amino acid needs. Protein is available from plant-based sources, but they aren't ideal because it's difficult for them to provide all the amino acids your pup requires. Fat supplies your dog with energy, giving him twice the energy that proteins or carbohydrates provide him. As well, fat provides insulation, protects your dog's internal organs and is a source of essential fatty acids. Despite their bad rap, carbohydrates are a good source of energy and fiber for Dexter. He also needs ample vitamins and minerals, most of which come from his diet.
Feeding What He Needs
Though Dexter's ancestors relied on what they could hunt, kill and dig up, he has a much easier life now. The choices for dog food have changed drastically over the past 30 years, and there are a wide variety of commercially available options to mimic what he would regularly eat if he were left to his own devices. PetMD recommends reading your chosen dog food's ingredients, paying special attention to the first three ingredients, which will tell you if the food is plant- or animal-based in its protein sources.
You've likely learned a dog will often eat things he doesn't need, if given the opportunity; unlike cats, dogs aren't known to be finicky eaters. It's normal for dogs to eat grass, though there's no scientific evidence why they do. If Dexter noshes on grass, he may want some additional roughage, he may have an upset belly or he just may enjoy the taste. Unless he eats grass to the extent he loses weight from excessive grass-induced vomiting or has diarrhea, Dexter's just doing what many dogs regularly do.