Senile Dementia In Dogs: What Does Science Say?
Veterinary medicine aimed at geriatric-age pets is advancing rapidly. This is because more and more companion animals are reaching this stage, thanks to the care of their guardians and the evolution of veterinary medicine for small animals.
Unfortunately, while pets are living longer, more age-related illnesses are also appearing. This is the case with senile dementia in dogs. This canine pathology is comparable to dementia in humans – a good example is Alzheimer’s – although there are other neurodegenerative diseases associated with this event.
Scientist WW Ruehl, along with his collaborators, coined the term “cognitive dysfunction syndrome” to explain the degeneration suffered by the brains of some elderly dogs that caused certain changes in the animal’s behavior.
What are the changes that occur in the brain during senile dementia in dogs?
Cognitive dysfunction syndrome or senile dementia in dogs is a neurodegenerative disease typical of older dogs. This does not mean that all elderly pets suffer from dementia, it does mean that it is at this age that it appears.
As with humans, dogs’ brains also change when they reach old age. These are normal changes that, although they can cause certain changes in behavior or personality, are not pathological. These changes are as follows:
- Cortical atrophy, which usually causes a progressive decrease in vision.
- Thickening and calcification of the meninges. Calcium is deposited in the meninges rather than in bones or teeth and this can interfere with brain function.
- Dilation of the ventricles, which are part of the system through which cerebrospinal fluid circulates.
- Widening of the grooves and retraction of the convolutions. In other words, the brain seems to shrink.
- Glia reactivity, which are nerve cells involved in maintaining neurons and processing the information that travels between them.
Many of these changes can also appear in senile dementia processes in dogs. However, one of the most important factors discovered so far and which also appears in Alzheimer’s in humans is the presence of deposits of a protein called β-amyloid.
Accumulation of beta-amyloid during cognitive dysfunction syndrome in dogs
The β-amyloid protein accumulates in the spaces between neurons in different parts of the brain, such as the brain parenchyma or its vascular vessels. This accumulation is called neuritic, senile, or amyloid plaque.
Although it is not yet known exactly how these protein depositions work, the neurotoxic properties of β-amyloid are known. This compound compromises neuronal function, causes damage to synapses, kills neurons, and causes the depletion of neurotransmitters from these dead cells.
According to studies, depending on the size of the neuritic plaques, the degree of severity of senile dementia will be greater or lesser. This fact is very similar to what happens in the human brain when you suffer from Alzheimer’s.
Genetic inheritance and senile dementia in dogs
Some dog breeds seem to have a greater predisposition than others when it comes to suffering from cognitive dysfunction syndrome. This fact is related to mutations in several chromosomes, which cause the overproduction of the β-amyloid protein.
Research suggests that while small-breed dogs live longer, they are not as prone to dementia as medium- or large- breed dogs . Likewise, some scientists have observed that females are more likely to develop this dysfunction than males.
Treatment of cognitive dysfunction in dogs
Many of the symptoms of senile dementia cause the relationship between the guardian and the dog to deteriorate so much that the person decides to euthanize or abandon it. The problem arises when the dog is diagnosed with senile dementia, as the condition has no cure or ideal treatment.
Treatment is usually aimed at treating and reducing the anxiety state that dogs with this disease often experience. In short, in a very short period of time, the dog ceases to understand the world around him and suffers so much stress that he starts to present behaviors that are undesirable for the tutors, such as aggressiveness or excessive vocalization.
Currently, the treatment used for dogs with dementia generally consists of a set of therapies that include specific behavioral guidelines to deal with the animal, various medications, nutraceuticals and specific diets.
Unfortunately, like Alzheimer’s, senile dementia in dogs is not curable and the process simply needs to be dealt with in the most gentle and empathetic way possible. The dog is totally unaware of what is happening to him and simply responds as his nature guides him.
