As much as we resist accepting it, the fact is that our beloved pets do grow older and inevitably the day comes when they are classified as "geriatric". Cats age more slowly than dogs and do not appear to show breed differences in aging characteristics. Dogs, however, show great variation in aging due to both size and breed, with small dogs generally aging more slowly than large dogs. Indeed, large dogs can become geriatric as early as 7.5 years of age.
Like humans, dogs and cats experience numerous physiological and behavioral changes with aging. Organs function less efficiently, senses are dulled, and skeletal and muscle mass decline. Hence, geriatric pets have specific nutritional needs that must be met to ensure that they experience the highest quality of life possible during their golden years.
OLD DOGS
Dogs typically lose lean body tissue as they age, changing their ratio of body fat to body lean. Indeed, body fat can almost double in older dogs. This occurs in conjunction with a decrease in the animal's resting metabolic rate (basically how fast it burns calories at rest), since muscle is considerably more metabolically active (calorie-burning) than fat. Many older dogs also tend to be less active, which further contributes to a decrease in muscle mass and metabolic rate. Therefore, unless an older dog reduces its food intake or maintains it activity level, it will likely gain weight. A decrease in both activity and metabolic rate can reduce daily energy requirements by as much as 40%!
Nutritional products designed for the older dog become important to a continuance of quality of life for your pet. A decrease in energy content of the diet may be appropriate for more sedentary older dogs, but high-quality protein must continue to be supplied in order to maintain lean body tissue. Research has shown that older dogs actually need more dietary protein than younger dogs in order to maintain optimal muscle mass. Historically, people have believed that high dietary protein contributed to renal (or kidney) failure in older dogs. Research has disproved this; high dietary protein will not harm a healthy kidney or contribute to its decline. However, dogs of any age with renal disease do need dietary modification to support their metabolism in the face of clinical kidney insufficiency.
The older dog also experiences changes in fat metabolism, one of which is a decreased ability to synthesize certain omega fatty acids from other dietary fats. There is some evidence that these changes may be breed- as well as age-related. This suggests that food designed for older dogs should be supplemented with omega-3 and –6 fatty acids in order to maintain healthy skin and hair.
Age can also impair the canine immune system, and this may, again, be breed-specific. Early research indicates that antioxidants such as vitamin E, beta carotene and lutein may be beneficial in supporting immune health in the dog.
It is of primary importance for overall health to keep your older dog as active as possible. While the aging canine may not be able to chase down a tennis ball or follow a bicycle as he once did, he still needs significant exercise to maintain muscle mass, metabolic rate, and joint health. Two brisk 15- to 30-minute walks per day will keep your dog far healthier than allowing him to settle into a sedentary lifestyle or assuming that he will get enough exercise on his own if left in a fenced yard. He will need your help to ensure that he stays physically active and as healthy as possible.
Your aging dog must rely on you to keep the quality of his life as high as possible. Remember to make sure he has adequate exercise, plenty of clean, fresh water, regular trips to the vet, and a senior dog food (such as Exclusive® Senior) designed to meet his very special needs. After all, he's been your very special friend for years – he deserves the best!
OLD CATS
As in most things, cats are different from dogs in how they age. Cats do not appear to show breed or size differences in aging, perhaps because the difference between a small and large cat is not nearly as great as that between a small and large dog. In addition, the metabolic rate of a cat does not decline with age as much as a dog's, possibly because young adult cats are not that much more active than older cats. Cats also lose less lean tissue and gain less fat tissue than dogs due to aging alone, though this certainly does not mean that they cannot become obese or that their body composition does not noticeably change as they age.
Aging cats do experience a decline in dietary energy digestibility, primarily due to a decreased ability to digest fat, which can also decrease the availability of the omega fatty acids. Most older cats will make up for this deficiency by simply eating more food. However, like the dog, the cat's energy requirements decrease with age, so the older cat that increases its intake may eat too many calories and gain weight. Some cats will need to be fed controlled portions to aid them in weight management. This means the fat in the diet will need to be high in omega-3 and –6 fatty acids in order to meet the needs of the older cat whose intake must be regulated. Cats will also need an adequate source of high-quality dietary protein in order to maintain muscle tissue. Being true carnivores, cats have a high need for dietary protein, and this does not diminish with age.
While only preliminary research has been done with cats, indications are that antioxidants such as vitamin E, beta carotene and lutein may be beneficial for enhancing sagging immune systems in geriatric cats. More work is needed in order to more specifically determine the effect of age and dietary antioxidants on immune system health in cats.
Exercise can benefit a cat just as it does a dog. Playing with your elderly cat or encouraging him to move around will help to keep him healthier longer and help him manage his weight better than if he lapses into a completely sedentary lifestyle. Try keeping his litter box and food at opposite ends of the house or on different floors to encourage more movement.
Foods designed for geriatric pets should contain adequate levels of high-quality protein, the appropriate amount of energy from fat rich in the important omega-3 and –6 fatty acids, and antioxidants. The right food will help your aging pet receive the nutrition he needs without risking the weight gain that can predispose him to obesity-related diseases. You just add the exercise and the love to help your best companion continue to be your buddy for many more years!
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