Age is not a disease. Veterinarians commonly say this in response to pet owners’ comments that animals are sick just because they’re old. While certainly age isn’t a disease, it’s clear that with aging comes disease. This is true for both people and pets — and for certain exotic pets, such as large parrots and many reptiles, who can live as long as many people, the parallels between disease in people and animals are clear.
Five Common Diseases That Affect People and Pets
Atherosclerosis: Atherosclerosis, or hardening of the arteries, occurs when fat (cholesterol and triglycerides) is deposited inside blood vessel walls as plaque, making vessels stiff, rigid and unable to pump blood effectively. Deposits can become so large that they can either block the blood flow or rupture, causing clots. If blood vessels to the brain are blocked, this can cause a stroke. If blood vessels to heart muscle are blocked, this can cause a heart attack. These scenarios can occur in both people and pets.
Long-lived pet parrots, particularly Amazon and Quaker parrots, who may live 20 to 50 years, are prone to development of atherosclerosis. Like people with atherosclerosis, pet Amazons are commonly overweight, sedentary and often consume a high-fat (predominantly seed) diet. However, studies have shown that while parrots fed high-fat diets can develop atherosclerosis, not all seed-eating birds develop this condition. So it is likely that in birds, just as in people, genetic factors also play a role in the development of this disease.
Veterinarians generally diagnose atherosclerosis in birds from the presence of clinical signs (for example, weakness and sometimes fainting when birds with rigid blood vessels get stressed and can’t pump blood to their brains fast enough) as well as obvious lesions on X-rays. While humans may be treated with blood vessel catheterization to remove dangerous fatty plaques, obese birds, because of their small size and big anesthetic risk, are generally treated simply with low-fat diets, increased exercise and sometimes fat-lowering drugs. These treatments help lessen the likelihood that a parrot will suffer a stroke or heart attack from these fatty plaque deposits. Veterinarians recognize successful treatment of affected birds by disappearance of weakness and fainting and lower blood cholesterol and triglyceride levels.
Arthritis: This degenerative joint disorder, marked by joint inflammation and pain, is seen often in birds and guinea pigs. Since the incidence of arthritis increases with age and obesity, it is not surprising that this condition occurs in large parrots, who may live in captivity for more than 40 years and who often become obese from chronic lack of exercise and consumption of high-fat, all-seed diets. Poor nutrition and excess weight can strain joints and may predispose a bird to development of arthritis. Bird owners must recognize arthritis-related changes in their pets and make adjustments to cages (perch height, access to food bowls, etc.) to make getting around easier for them.
Like parrots, older guinea pigs commonly develop arthritis in their knees, particularly when their diet lacks vitamin C. Dietary vitamin C is crucial in all guinea pigs to help maintain healthy joint cartilage. Guinea pigs cannot make their own vitamin C, so they must receive vitamin C supplements. Guinea pig owners often mistakenly think that feeding vitamin C-enriched guinea pig pellets or vitamin C-rich vegetables and fruit will provide adequate vitamin C.
However, the average shelf life of vitamin C in pelleted food for guinea pigs is only three months from the time it is manufactured. Since it may take more than three months for pellets to go from the manufacturing plant to the pet stores to an owner’s home, by the time the pellets are consumed, the vitamin C content may be at less than adequate levels. To ensure guinea pigs are getting enough vitamin C, owners can administer vitamin C tablets daily under a veterinarian’s guidance. Proper nutrition for guinea pigs is essential in helping to decrease the occurrence of this debilitating disease.
Kidney failure: Regardless of species, animals who live long enough ultimately experience kidney function decline that may lead to failure as they age. The kidneys clear toxic byproducts of digestion from the bloodstream. As the body ages, kidney function slowly declines until the kidneys become unable to perform effectively, leading to buildup of toxins in the blood and, eventually, to death. Kidney failure is particularly common in older rabbits. As with people, rabbits with kidney failure often drink and urinate frequently and pass very dilute urine. Their appetite decreases, and they lose weight. In both people and pets, eating a balanced diet and staying hydrated may help delay the onset of this condition.
Gout: Gout, a painful condition caused by buildup of uric acid (a byproduct of digestion) in the blood, afflicts people, birds and reptiles. In all species, uric acid is a crystalline substance normally excreted in varying amounts by the kidneys. In people, it dissolves in blood and leaves the body in urine; in birds and reptiles, it is excreted as a solid waste product so that these animals can retain water. When kidneys don’t function properly to excrete uric acid, it precipitates in blood and deposits in joints, causing painful arthritis, and in kidneys and other vital organs, leading to organ failure, kidney stones and death.
In birds and reptiles, gout is associated with lack of dietary vitamin A, excessive dietary vitamin D, severe dehydration, administration of potentially kidney-toxic antibiotics and certain viral and bacterial kidney infections. Treatment includes increased fluid consumption to improve hydration, diet changes, administration of drugs to control pain and to decrease uric acid production and simultaneous treatment of other diseases. Nutritional requirements for exotics are complex, so any dietary supplementation should be done under the supervision of a veterinarian.
Cataracts: Cataracts — a change in the lenses of the eyes from clear to opaque — occur when lens proteins degrade. Cataracts also may develop as a result of excessive exposure to ultraviolet light, genetic predisposition, eye trauma, administration of certain medications or the presence of other diseases. Over time, the lenses become more opaque and are less able to transmit light, ultimately leading to loss of vision. People and pets with significant visual impairment may have surgery to remove cataracts. While cataract removal is simple in most people, many exotic pets have very small eyes, making cataract surgery difficult.
Veterinary Attention Is the Best Prevention
While these diseases are interesting because they are ones we may share with our exotics, they also point out the need for regular, routine veterinary care. Exotic pets, like all pets, should see a veterinarian at least annually, if not more frequently, to help prevent these diseases from occurring. People and pets may suffer from similar medical conditions, but treatment of exotic pets is often more challenging because of patient size, increased risk and expense and therefore should only be attempted under the guidance of a veterinarian well-versed in the specific biology of these unique and fascinating species.