Changes in Behavior Associated With Aging in Dogs

An old dog is a special friend. We remember the times we shared and are often saddened by the changes we see. As our companions age, they undergo both physical and metabolic changes that affect our interaction with them. These physical and metabolic changes can often manifest themselves as behavioral changes. Understanding these changes can help increase our enjoyment of the “golden years.”

Musculoskeletal Changes

The aging dog undergoes many physical changes as time passes. Within the Musculoskeletal system these changes can be profound. Many older dogs develop arthritis in their joints and spondyliti changes the spine. Geriatric dogs also show a decrease in muscle mass. These changes may be accompanied by outward physical manifestations that the owner can see. When arthritis is present, the animal may limp or hold up the affected limb, or the joint may be painful to movement or touch. In the case of spondylitis, the animal may be unwilling or unable to go up and down stairs, jump on furniture, or even sit comfortably. These changes in mobility can then affect the dog’s behavior. A dog that can no longer follow its owner from room to room may become depressed. Dogs are social animals and wish to be with their family, but if they are unable to dog so because of mobility problems, they may suffer the effects of isolation. One solution may be to give the dog a resting place that is the center of activity and does not require the dog to move to be with people.

Because of loss of muscle mass, the older dog may need a softer place to lay down and may no longer be able to lay on a hard floor. This too needs to be considered so that the dog can join in with the family.

These musculoskeletal changes can make it difficult for older dogs to walk on smooth or slippery surfaces such as wood, tile, or linoleum floors. Non skid area rugs strategically placed may enable the dog to navigate the home.

Changes in the animal’s joints can often be accompanied by pain. Some dogs show very little evidence of pain, while others become irritable. this irritability can lead to aggressive encounters with family members and visitors. In consultation with a veterinarian, medications can be given to decrease pain and therefore increase the dog’s ability to interact with people. Accommodations in sleeping arrangements and walking surfaces need to be considered to maximize the dog’s comfort and minimize pain.

Decreased mobility also affects how the pet may react to stressful events. Previously, the dog may have moved away from such a situation, but in its present condition, a lack of mobility or an unwillingness to move may require the dog to stay. This can result in a fearful situation for the dog that leads to aggression. One example is an older less mobile dog in a home with a new, very mobil baby. The dog may be unable or unwilling to get out of the way of the baby, yet it may find the constant intrusions of the child unwelcome. This may lead to aggression toward the baby in an attempt to get the child to leave. Carefully monitoring the interaction and watching the dog for signs of stress or fear are important. If the dog shows any of these reactions, then remove the dog from the situation for its comfort and the child’s safety.

Visual Changes

Alterations also occur in the visual system of an elderly dog. The most common change is nuclear sclerosis, a hardening of the central portion of the lens that results in a clouding of the lens. While overall vision appears to be unaffected in advanced stages, a dog may have problems visualizing near objects, for example, food dropped on the floor.

The most common age-related visual change that results in a behavioral change is the formation of cataracts. This can result in a functional vision loss that is noticeable to the owner. One of the greatest difficulties for the blind dog is any change in routine. Often he navigates familiar surroundings very well, so well, in fact, that owners often are unaware at first that the dog is blind. When furniture is moved or the dog is taken to a new location, the owner then notices visual deficits. If the visual loss is coupled with a hearing loss, an area of concern is possible aggression if the dog is reached for or touched while sleeping. If the dog’s hearing is intact, people should speak to the dog prior to touching it.

Hearing Changes

Deafness is another common condition that accompanies aging in dogs. three common problems arise out of deafness. The first is a loss of control and ability to discipline the dog. A dog that was previously well trained may begin to be difficult to control. With time and patience. the dog can be taught to respond to hand signals for common commands such as sit, down and come. Occasionally, these dogs can still hear loud sounds or vibrations, and stamping the floor may be used to get their attention so that you can give the hand signal.

Secondly, some deaf dogs may begin to bark uncontrollably. Often this behavior is inadvertently encouraged by the owner who gives the dog food treats to stop the barking. A strategy that can be more effective is isolating the dog until the barking stops, even if it is only for a short time. As soon as it is quiet, let it out and reward the quiet behavior.

A third problem with deafness is the threat of automobiles. Many dogs seem to avoid cars by the sound, and when they are deaf, they are at extreme risk for injury, often in their own driveway.

House Soiling

House soiling can be a major problem in geriatric dogs, and one that frustrates owners. Kidney function does decline with age. There is also some evidence that the decline in kidney function is related to changes in the brain of elderly dogs. At the present time, a new drug being tested by Deprenyl Animal Health, Inc. (Overland Park, Ks.), seems to have an effect on inappropriate urination in geriatric dogs.

Concurrent medical problems need to be investigated to rule out metabolic causes of urinary incontinence or inappropriate elimination. For some older dogs, an increase in the frequency of access to the outside is helpful in controlling house soiling. If the dog must be left alone for long periods, paper training may be helpful. Often owners resort to isolation of the dog to avoid ruining household possessions. This can lead to other problems of loneliness or barking for attention. One possible solution is to keep the dog on a leash while with people so that it can alert someone to its need to go outside and cannot wander off to eliminate in the house.

Defecation can also be a problem due to loss of sphincter control. Dogs also respond to stress by soiling the house with stool. If the stress can be identified, the animal can be acclimated to the change and hopefully the house soiling will subside.

Mourning

Many animals today live in multi-pet households and therefore have house mates that they share experiences with well into old age. A common behavioral problem for older dogs is mourning for the loss of a house mate. Although there has not been a great deal of research on mourning in pets, it is well known that pets form attachments to other animals they live with, and anecdotal evidence indicates that animals grieve over the loss of their companions. For some animals this grieving process may be short, or it may not be evident or visible to the owner. For other animals, especially geriatric pets, mourning can be a real phenomenon with behavioral ramifications.

Dogs may undergo several behavioral changes after the loss of a companion. these include a decrease in appetite and activity, possible anxiety or restlessness, depression, or sleep disturbances. Some animals have been observed to be “searching” for the missing companion. While not all of these reactions occur, they are not uncommon. These changes often abate over time, especially if the owner attempts to follow a few of these suggestions.

Keep the routine as close to the previous routine as possible.

Avoid rewarding negative behavior changes with petting or food.

Create opportunities for positive associations with the dog. Additional walks, playtime, or games can help ease the transition.

It is important to realize that the dog is mourning the loss of a specific companion, so replacing the lost companion with another pet is often the solution to the problem.

These changes can occur with the loss of a human companion as well. For example, if one member of a family, with whom the dog was closest, leaves or dies, the dog may start exhibiting behavioral changes unless the surviving member of the family puts time in with the dog.

Whenever there are changes in eating or drinking in an elderly dog, they may signal health problems and should never be ignored. Veterinary attention should be sought to rule out a possible metabolic cause.

Changes in Routine

Geriatric canines can be very resistant to change. New routines, new locations, and increased social situations can be stressful to the elderly dog. In some situations, it may be better to isolate the dog to avoid short-term stress. These include situations with many visitors, visits from small children, or the presence of workmen in the home. Sometimes, the new situation cannot be avoided. Changes in location and territory, for instance, when a family moves to a new home, can result in behavior changes such as house soiling. Care must be taken to give the dog adequate time to eliminate in a new location and perhaps to provide a surface that is similar to what the dog was used to previously. If a dog is used to going out into a yard to eliminate and now has to eliminate while on a leash, time and patience are necessary to change old habits. Praise and rewards are much more effective in changing behavior than scolding or punishment. The following example illustrates this point.

A 9 year old German Shepherd was eliminating in the home. It has a previous history of urinary marking, from time to time, but now was soiling with stool and urine to an excessive extent. For the past 8 months, there had been a great deal of construction around the grounds of the house, and the dog was no longer being walked three times a day.

Concurrently, the hose soiling began. On examination, the dog showed lack of normal gait in the rear legs. Because of the construction work, the dog was now being asked to go out into a dog pen and eliminate on gravel. The change in surface was uncomfortable for the dog, and it therefore was eliminating in the house. A return to walks helped abolish the problem.

Changes in Social Structure

In multi-dog households, there usually exists a social structure in which one dog is the dominant animal. This often can be the dog who was there first, usually the older dog. As a dog ages and a young companion matures, there can be dominance challenges from the young dog toward the older dog. When size is a compounding factor, serious damage can occur. An older dog may have to relinquish its dominance role to the younger, stronger and bigger dog. If the fights are severe, the professional assistance of a behaviorist should be sought.

Cognitive Dysfunction

Recently, the veterinary literature has discussed a group of age-related changes in dogs and grouped them together under the heading of canine cognitive dysfunction syndrome. These behaviors include circling, tremors, stiffness or weakness, inappropriate vocalization, compulsive behaviors, and changes in sleep patterns, house training, interest in food, attention and activity, and awareness of surroundings.

The dog may exhibit separation-related behaviors where it never has before, uneasiness with visitors, and other problems discussed earlier in this article. Trials with drugs used to treat Parkinson’s disease in humans have been shown to be useful in some dogs for selected behaviors. Hopefully, one or more of these drugs will be marketed to help control some of these age-related cognitive changes in dogs.

Summary

Many changes take place both physically and behaviorally as a dog ages. With good veterinary care, love and patience, our friends can live a long and comfortable life while bringing us joy.

Definitions:

Arthritis–inflammation of a joint

Cognition–awareness and judgment, which is important in daily functioning

Cognitive Dysfunction–a term used in aging dogs to describe the loss of awareness and judgment

Geriatric–referring to the process of aging nuclear sclerosis

Nuclear Sclerosis–hardening of the central portion of the lens of the eye

Spondylitis–inflammation of one or more of the vertebrae

References