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Obesity is now the most prevalent form of malnutrition in dogs and cats today. One recent study found that over 25% of dogs and cats seen by their veterinarian were either overweight or obese!

Fat Cat

The incidence increases to an alarming 40% in dogs and cats between the ages of 5-12 years old! Yet most pet owners fail to recognize their pet’s weight issue.

Additional weight can be detrimental to your pet’s health. Nestles Purina has developed a body scoring system that is often helpful to dog and cat owners as they struggle to realize their pet’s weight problem.

Dog Body Condition Scoring System
Cat Body Condition Scoring System

Obesity can reduce your pet’s lifespan and can be responsible for many chronic medical problems. Problems associated with obesity include: increased anesthetic and surgical risks; heart disease due to overwork); respiratory issues associated with decreased exercise and endurance; arthritis as well as strain on tendons and ligaments; liver disease (Hepatic Lipidosis); heat stroke (due to an inability to dissipate heat); skin problems (excess skin folds creating moist dermatitis); anal gland impaction or infection and dystocia.

Further, there are several diseases that have obesity as one of the presenting clinical signs. Among these include: Diabetes, Hypothyroidism and Hyperadrenocorticism. Note: These diseases should be ruled out prior to implementing a weight loss program in your pet.

Even though there are genetic variations and different metabolisms among animals, the cause for 90% of all obesity cases is overfeeding! Additional causes include: lack of exercise, lowered metabolism (as a result of spaying and neutering) and hormonal imbalances.

Think of fat as an endocrine organ…When all of the fat cells are full, they begin dividing. As fat cells divide, changes occur to metabolism and hormones. Fat cells produce the hormones Leptin and Adiponectin. Leptin controls metabolism and appetite. As your pet becomes heavier, it becomes Leptin resistant. This means that the animal ALWAYS thinks it is hungry and NEVER seems satiated! As a result the metabolism slows even further. It takes even less food for the animal to maintain itself! It becomes a vicious cycle.

On the other hand, Adiponectin manages fat lipids, glucose and has direct control over the way a body metabolizes Insulin. Yet, this hormone is down-regulated and becomes much less effective as weight gain continues! It’s easy to see how overweight animals become Diabetic.

Dog Eating

Most pet owners choose to feed their pet’s free-choice. It’s simply more convenient. This means that they refill their pet’s bowl when it gets low or empty and therefore have no idea how much their furry friend is consuming. One study found that cats fed free-choice experienced a 40% weight gain within a 12 week period following early spaying and neutering! The reason for this is because after altering, the metabolism decreases by 30-40%. So free-choice feeding must stop after pets are altered! Additionally, their food intake should be decreased by 25-30% due to their “new” slower metabolic rate.

So how can we as pet owners get a better handle on our pet’s weight? First, we must have FULL cooperation from everyone in the family. Weight loss incorporates appropriate dietary, exercise and behavioral modification. We must realize what and how much we are feeding. Free-choice feeding must be eliminated; instead, feeding “timed” meals in which food is measured out and the pet is allowed a certain amount of time to consume it before it is put away until the next meal. Pets object to this method at first, but quickly comply.

Dog Measuring Cup Cat Measuring Cup

Owners must realize that feeding the amount of recommended food on the bag is NOT necessarily the amount the pet may need. Most of the feeding amounts listed on food bags are for INTACT animals! If a pet has been altered, it will require 30% less food due to its lowered metabolism.

Additionally, feed diets that are recommended for weight loss (ex: Hills RD, WD or Metabolic Diet, Purina OM). Diets should be fed based on the ideal weight of the pet, NOT the current weight. It is also important to limit the number of snacks and treats a dieting pet has access to. Feeding snacks that are “weight loss” treats helps to ensure that pets don’t get too many unnecessary calories.

It is important for owners to weigh their pets regularly while they are on their diet. Adjustments may need to be made depending on the pet’s activity level. Then once the desired weight is achieved, a maintainance program will need to be implemented. As in people, weight management is a lifelong process in our pets.