Cats are “obligate carnivores.” Here’s the definition, straight from Wikipedia: “Obligate carnivores, or “true” carnivores, are those carnivores whose survival depends on nutrients which are found only in animal flesh. While obligate carnivores might be able to ingest small amounts of plant material, because of their evolution they lack the necessary physiology required to digest that plant matter.”
There are a number of articles on the rationale for feeding cats canned food (or freeze-dried raw or homemade) rather than kibble. These arguments are extremely compelling!
There an article by Lisa Pierson, DVM, Feeding Your Cat: Know the Basics of Feline Nutrition. While it does read like a diatribe against kibble for cats, at the same time she gets very specific with quantifying proteins, fats and carbs, which is extremely helpful in trying to figure out just what canned food to give. She also has a section on how to transition your cats from kibble to canned food. She also explains just why many cats prefer kibble to canned:
“One reason that cats like dry food so much is because the pet food companies do not play fair when manufacturing this sub-optimal food source. They coat the kibble with extremely enticing animal digest sprays which are very pleasing to a cat – making a poor quality diet very desirable to the target animal.”
She also makes the interesting point that fish is very bad for cats, on a number of different levels; not only because of composition and toxins, but also that the taste is apparently highly addictive to cats! Another point of note is that “pouch” foods contain too much water, which makes their nutritional value considerably lower.
In Cat Food – Natural Composition she explains why it’s necessary to use the Typical Nutrient Analysis (TNA) rather than the Guaranteed Analysis (GA) which is what is on the cans; you have to get the TNA from the manufacturer directly. OR! She also has put together a WONDERFUL gdocs spreadsheet of 1169 commercial cat foods available with the protein, fat and carb percentages according to the TNA. She also includes phosphorus, but since she gives no numerical range to aim for, it’s pretty useless. You can sort the chart by the various columns but you can’t edit it. However! If you save it to your own computer or google drive, then it is editable and you can save changes, as it’s your own document then. I’ve done this to add my own notations, highlight particular food types that seem to have the best balance, etc., (as well as changing the font slightly smaller) so I can print out and take to the pet store with me when shopping.
- Protein over 40%
- Fat under 50%
- Carbohydrates under 10%
- Moisture 75-78% (pretty standard and not on the chart; you’d need to check the can itself; pouches have too much water!)
There’s an even better article by Jean Hofve, DVM, “Why Dry Cat Food is Bad” that very simply and clearly lays out an excellent case against feeding kibble to cats.
To summarize: “The carnivore’s ideal diet is essentially the Atkins diet: lots of protein and fat, and a small amount of complex carbohydrates from vegetables.”
Some pertinent points are below. But these are just highlights I found most compelling; you need to read the whole article, it’s fabulous, and eye-opening!
- Ingredients: “Dry food is typically made from rendered ingredients, such as chicken meal, poultry by–product meal, and meat and bone meal (MBM).” … “Some rendered products are better—or worse—than others. Chicken meal, for instance, is likely to be relatively pure, because the rendering plant is usually associated with a slaughterhouse that processes only chickens. On the other end of the spectrum, MBM is the “dumping ground” of the nastiest raw ingredients.”
- Dehydration: “Obviously, dry food is dry. This is a very big problem for cats, whose ancestors are desert-dwelling wild cats. They have passed on their super-efficient kidneys, which are designed to extract every last drop of moisture from prey animals. As a result, cats have a low thirst drive, and don’t drink water until they are about 3% dehydrated—a dehydration level so serious that most veterinarians would consider giving intravenous fluids. Dogs have a higher thirst drive and will drink more readily, so they are less prone to serious dehydration. Dehydration causes or contributes to many serious health issues, including urinary crystals and stones, bladder infections, FLUTD, constipation, and kidney disease.”
- Carbohydrates: “While classified as carnivores, dogs (and humans) are, in practice, omnivorous, meaning they can use pretty much any food as fuel. They use carbs directly for energy by breaking them down to simple sugars. Strictly carnivorous cats preferentially use protein and fat for energy, and these pathways are mandatory. Felines can digest and absorb carbohydrates, but those carbs mostly turn quickly and directly into fat.”
- Calories: “Dry food is a highly concentrated source of calories. Dry food, not canned food or any other high-moisture food, is where the calories are. Dry food is the leading cause of obesity in pets.”
- Contaminants: “Given the types of things manufacturers put in pet food, such as pesticide-soaked grains and diseased, dead, and dying animals, it is not surprising that bad things sometimes happen. Ingredients used in pet food are often highly contaminated with a wide variety of toxic substances. Some of these are destroyed by processing, but others are not.”
- Allergies: “As mentioned briefly above, the high-heat processing that dry food undergoes during manufacturing can denature proteins, meaning that it distorts their shape. To a protein, shape is everything, and only a protein in the correct shape will function properly. Shape is also how the immune system identifies proteins that belong in the body (“self”) versus foreign proteins. When an abnormal protein is picked up by an immune cell and antibodies are produced, then every time that protein appears, antibodies flock to it and stimulate inflammation. More bad proteins = more inflammation.”
In this fabulous article, again by Jean Hofve,DVM, Switching Foods, it’s made clear that our “finicky” cats, aren’t actually just being finicky! They are addicted to a particular food type/taste/texture!
“The last big reason to change foods periodically is to prevent finicky eating habits. Pet food makers are masters at making the food irresistibly tasty. Consequently, an animal fed a single food may become “addicted” to it.” … “Many cat guardians have tried—and failed—to switch their cat to a better diet. A primary reason for that is the tendency of cats to turn their noses up at any new food.Cats often require more a more gradual (that is, sneaky) approach,”
TIPS AND TRICKS: And there’s a solution! Dr. Pierson’s article also covers this; my kibble-addicted cat was thrilled to get wet food with a quarter teaspoon (one-fourth packet) of Feline Forti-Flora sprinkled on it! I found it also helped by giving him canned food with some texture, such as shreds or grilled. BUT… food that has “sauce” or “gravy” has far too many carbs, as starches are needed to make the sauces and gravies. I also make his life happier by giving him Wysong Optimize Supplement as hand-fed treats…he particularly loves the Wild Caught Salmon, he just goes insane with happiness and likes to pounce on it and toss it around before gobbling it down! I’ve never seen him this enthusiastic about ANY of his food (or even toys) as he is about the Optimize! The powder I sprinkle on his canned food like the Forti-Flora to make it tastier. Please note, the manufacturer sells Optimize as a *supplement* which is fine, but they also state it can be used as a regular diet… it cannot! First and foremost, it has 4% moisture, and the cat’s regular diet should be 75-78% moisture (that’s one of the main reasons why we’re taking them off dry food in the first place!)
One point that’s been stressed in several articles: COST is not an indicator of quality! Some of the most expensive cat foods (whether dry OR canned) are not the best quality but those that are… surprise surprise! ….heavily marketed and promoted. Hill’s is definitely one to stay away from and is mentioned specifically in a number of articles (by different authors).
I was so impressed with Dr. Hofve’s articles, I thought I’d give her book a plug here! What Cats Should Eat, available in Kindle on Amazon. Freshly updated for 2018! This Amazon best-seller clearly explains everything you need to know about feeding your cat.
- Another interesting and brief article explains in layman’s terms, What Exactly Is An Obligate Carnivore? by Feline Nutrition Foundation.
- Here from PetMD is How a Cat’s Nutritional Needs Are Different From a Dog’s.