OVERWEIGHT PETS
Over weight animals or pet obesity is an excess of body fat that is enough to impair the health,
welfare and lifestyle of the animal.
When experts speak about humans being obese, they usually define it as being 20-25 per cent
above ideal body weight. However, in animals, the degree of obesity that impairs health,
welfare and quality of life has not been fully defined and will vary from one individual animal to
another, but it is more likely to be similar to that seen in people.
Obesity is a serious health issue in pets for several reasons:
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It affects millions across the globe.
It causes suffering and can be disabling for the animal.
It can affect an animal for a long period of its life.
It’s preventable.
Causes of Obesity
The main reason is the type of food being fed to the animal. If the animal eats too much and
does not exercise enough, they can become obese. However, there are some diseases that can
cause obesity also. Always check with your vet.
Is it Common?
Studies from various parts of the world estimate that between 22 and 44 per cent of dogs are
obese. There is a similar figure for cats.
Is Obesity Particular to Certain Pets?
There are certain reasons why a pet is obese.
Dogs:
Breed: Certain breeds of dog have a higher risk of becoming obese than others.
Age: The risk increases with age.
Sex: with the exception of older dogs, obesity is reported to be more common in females.
Owner: It’s been suggested that dogs owned by obese owners are more likely to be obese. The
reason is not clear, however, it may be because overweight owners are less likely to exercise
their dog.
Health Risks?
Obesity can cause welfare and health problems and make existing problems worse. This can
reduce both the length and quality of an animal’s life.
Some examples of medical conditions are:
Diabetes Mellitus or Sugar Diabetes
One of the most common complications of obesity in dogs is diabetes mellitus. Obesity causes
an increase in the secretion of insulin. This is in response to the increased blood glucose level
in the dog. When a requirement for insulin exceeds the ability of the animal’s body to produce
insulin, diabetes mellitus develops. If the need for insulin increases over a long period of time,
the cells in the pancreas which produce insulin can burn out, resulting in diabetes.
Complaints in Joints and Bones.
The bones, joints, muscles and associated tendons and ligaments work together to give the
animal smooth and efficient movement. If the animal is carrying excess weight, these can begin
to become damaged. As a result, arthritis can develop and the pain and joint changes
associated with hip dysplasia can become very severe. Also, extra tension on joints caused by
increased weight can lead to damage of certain ligaments.
What is a ligament?
A ligament is a tough, fibrous strand of tissue that holds one bone in proximity to another bone
in joints. There is a ligament in the knee; the anterior cruciate ligament. This is prone to strains
or tears. If this ligament tears, the knee becomes unstable and the animal is reluctant to use it.
Surgery must be carried out to repair this problem.
It is also worth mentioning that certain breeds of dog, Dachshunds, for example, are prone to
develop intervertebral disc disease or a slipped disc. If the dog carries extra weight they will
probably develop a painful and often debilitating condition.
Heart Disease.
Like humans, overweight dogs can develop an increase in blood pressure. The heart has an
increased workload because it’s pumping additional blood to excess tissues. This can lead to
congestive heart failure.
Problems with Breathing.
If an animal is overweight, the lungs can’t function properly as the additional fat in the chest
restricts the expansion of the lungs. Also, the extra fat in the tummy pushes against the
diaphragm giving less space in the chest for the lungs to expand on inspiration. Add to that, the
increased quantity of tissue is then putting extra demand on the lungs to supply oxygen. This
can be very serious in animals that already have a respiratory disease.
Heat Intolerance.
We all know, fat is an insulator. Great during the bitterly cold winter we’ve just experienced.
However, during the summer months; and, even though it never gets tropical here in Ireland, if
you’re an overweight dog, you are going to suffer and be less capable of regulating your body
temperature. Also, the liver stores fat, and when a dog is overweight, an increased amount of
fluids built up in the liver causing hepatic lipidosis. This can result in decreased liver function.
Surgical Risk
An overweight animal will take longer to come out of anesthesia. This is because many of the
anesthetics used are taken up by fat and the anesthetic must be removed from the fat by the
animal’s body. Also, many anesthetics are broken down by the liver. It’s obvious that a fatty
liver may not be as efficient at breaking down anesthetics and various other medications; thus
resulting in the possible delay in the animal’s recovery.
An increased amount of fat in the tissue makes surgery more difficult. It’s harder for the vet to
get to the area they are looking for. For example, in abdominal surgery in an obese dog, there
may be inches of fat between where the incision is made and the organ needing work, This
makes the surgery technically more difficult and the procedure will take longer; again,
increasing the anesthetic risk.
Giving Birth
An overweight dog will have more problems giving birth than dogs at their optimum weight.
This difficult birthing is known as dystocia. Dogs experiencing dystocia may need veterinary
assistance while delivering their puppies and may even require a cesarean section.
Constipation
An overweight animal has an increased risk of developing constipation and may have other
intestinal problems such as gas. This is not nice for the dog or for you, its owner.
Other Health Hazards
Obesity in an animal is linked with decreased resistance to viral and bacterial infections. For
example, salmonella and distemper appear to be more severe in overweight dogs. The causes
of this lowered resistance to disease in obese dogs in unknown.
Cancer
The link between obesity and certain forms of cancer is unknown. There have been studies
suggesting obese dogs tend to have an increased risk of developing certain types of cancers. A
recent study has found that dogs who are obese at one year old are at a greater risk of
developing mammary tumours.
So, we’ve set out a few facts on obesity for you; but how do you tell if your animal is obese?
Below are a few common, telltale signs to watch out for.
1. Excessive panting, particularly in hot weather
2. Lagging behind during walks
3. Sluggish behaviour
4. Reluctance to exercise resulting in fewer calories being used up, thus being stored as
fat.
Here’s a simple test:
Stand over your dog and check to see if his waistline is visible. There should be a depression,
even if only slight, behind his ribcage. This does not mean a bulge. Viewed from the side his
abdomen should not sag and it you run your hands over his chest area, you should be able to
feel his ribs easily.
Try and weigh your animal. A bathroom scales will give you a rough idea but if you can do it on
an electronic scales that will give you a better calculation of his weight. Your vet should have
one of these.
Talk to your vet and ask them to give your pet a complete health check in order to identify any
problems that may have arisen as a consequence of him being overweight. Also, it’s a good
way of ruling out conditions that may make the animal appear overweight, for example,
pregnancy or fluid retention or under activity of the thyroid gland-hypothyroidism.
Your pet’s weight loss regime should involve the entire family. Avoid feeding tidbits and sweet
treats like biscuits. It will take time and patience and a lot of restraint from you.
For more information please contact your veterinarian.