Humans who don't eat meat are starting to feed the same diets to their pets with catastrophic consequences.
Vegetarian and vegan diets are on the rise as people make conscious decisions to avoid meat and animal products in their diet, for a plethora of reasons. Two of the biggest reasons are nutrition and ethics.
But owners are beginning to funnel their dietary choices into the food they serve dogs and cats--even snakes. The results can be fatal.
Some animals, like cats, ferrets, and snakes, are obligate carnivores. Others, like dogs, can be omnivores but cannot survive properly on a strict diet of vegetables, fruits, and grains.
Most mammals make the essential amino acid taurine inside their bodies. Taurine is found in animal products, especially prominent in beef, lamb, and dark chicken meat. Raw meat has more taurine than processed meat kibble diets, which is one reason some veterinarians advocate raw diets for pets.
Because cats and ferrets cannot make taurine, they must receive it through their diet in substantial amounts and the right form in order to survive. The only way for this to happen is through a heavy meat diet.
Dogs, on the other hand, are seen as omnivores. While the modern domestic canine can metabolize some grain, this has only occurred during its co-evolution alongside omnivorous humans starting 10,000 years ago. Wolves--or the wild ancestors of house dogs--are carnivores.
A pet diet lacking in meat can also lead to magnesium deficiency, resulting in seizures. A heavy grain kibble diet in cats can result in bladder stones.
Despite needing meat in their diets, supplementing vegetables as snacks or "side dishes" can add vital nutrients to a pet's diet. In fact, though wolves and cats are carnivores, they will still eat grass in the wild when they have an upset stomach or are nutritionally deficient.
Squash, broccoli, pumpkin, carrots, sweet potatoes, and kale are some great additions to your pet's food bowl. Though your pets are not as efficient at metabolizing vegetable proteins, they can still glean other nutrients from the food.
There are still many animals who are strict herbivores, like guinea pigs and rabbits. These pets cannot metabolize meat protein.
Another reason meat-eating animals shouldn't be on meat-free diets is because pets cannot tell us how they feel. Additionally, there is still much left to be understood about their biology, whereas medical knowledge for humans has been studied in-depth, and many alternative dietary options are on the market.
So why do some studies say vegetarian or vegan diets can actually improve human longevity? Because of the different pathways for metabolizing food and the amount of knowledge and products available to make healthy, intelligent dietary decisions for people. There is still much to be understood about non-human biology.
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