Complete Care for Your Aging Cat - Amy Shojai [54]
By giving the cat the right balance of vitamins, the oxidation process is put back in balance and aging is slowed. “Vitamin E is one of the antioxidants that do this. In cats it works quite nicely,” says Dr. Carey. Research that measures the immune response on the cells themselves has shown that 250 milligrams per kilogram of vitamin E in the food can give the cat the immune competence of a much younger cat. “But if you go too high, you lose the effect,” he says.
In experimental studies, antioxidants lessened the severity of age-related hearing loss in rats. William W. Ruehl, VMD, says antioxidants may also prove useful for senile cataract treatment or prevention. “We’re going to see research just explode with regard to the antioxidants and cytokines and interleukins and these immune stimulators,” says Dr. Abood. She predicts that as pet food companies will apply all of this research even beyond “senior cat” diets. In other words, if it’s good for old cats, why not feed it to younger cats so they also get the benefits?
Since certain cancers show oxidation damage to DNA, theoretically, antioxidants should also help protect against cancer. Early studies seem to indicate that antioxidants reduce DNA damage, but it’s still too early to say for sure.
Brain Research
Wouldn’t the proper nutritional antioxidant mix also protect the brain, and keep cats “thinking” young? Yes, says Debbie Davenport, DVM, an internist and director for special education for Hill’s Pet Nutrition. In fact, a diet for dogs developed by Hill’s does just that. It contains a mix of antioxidants, along with other nutrients such as folic acid and L-carnitine. Studies at University of New Mexico, the University of Toronto, and in-home tests with dog owners have shown that Prescription Diet Canine b/d improves learning ability and alertness in older dogs, significantly reduces house-soiling accidents and disorientation, and improves sleep patterns and interaction with owners. Researchers found that cognitive ability in these old dogs also improved when their brains were “challenged” with new things to learn.
It is believed that aged cats with similar cognitive dysfunction may also benefit from antioxidant-enriched foods and keeping their minds agile. “We’re not nearly as far along with the feline product as we are with the canine product,” says Dr. Davenport.
The difficulty is twofold: first, it is hard to find a large enough number of cats of the appropriate age to participate in feeding trials, she says. Second, researchers historically have used dogs, and aren’t sure how to devise appropriate cognitive tests for felines and train the cats to perform them.
There simply haven’t been as many studies of cognitive disorder in cats as in dogs, says Kelly Moffat, DVM, a veterinarian at Mesa Veterinary Hospital in Mesa, Arizona. “They’ve looked at brain changes, and they’ve found some that cats seem to have the beta amyloid deposition that are similar to the dog or people that are showing [Alzheimer’s-like] behavioral signs.”
Dr. Moffat collected data from 150 cats over the age of 11 (some as old as 21) to track age-related cognitive changes. A similar study was conducted by Melisa Bain, DVM, at the University of California-Davis. Results support many veterinarians’ opinion that aged cats do, indeed, suffer from similar senility problems as aged dogs.
The onset appears to happen later (since most cats are longer-lived than dogs), and also may develop less frequently in cats than in dogs. But that may be a perception difference on the part of owners, says Dr. Moffat. “Dogs know a lot more commands, and I don’t think we hold cats to that,” she says. Dog owners may therefore notice the dog “forgetting” a command more readily than cat owners noticing a more subtle behavior change.