Some pets have a slower metabolic rate than others, and factors such as a low activity level, orthopedic disease, and spay or neuter status can impact how many calories a cat or dog needs each day. It is often helpful to go back to the diet history after calculating energy requirements and comparing current intake to the calculated energy requirement for weight loss. If the pet’s current intake is higher than the calculated amount, the veterinary team can proceed with the next step. If the pet is currently eating less than the calculated amount he or she needs for weight loss, it can be helpful to revisit the diet history. For canine patients, it can be beneficial to check thyroid hormone levels. It also can be helpful to consult a board certified veterinary nutritionist when the pet is eating less than the calculated amount for weight loss.
Diet selection for overweight animals
Animals with excess body weight should ideally be placed on a therapeutic weight loss diet. These formulas are nutrient-dense, meaning there is a higher concentration of protein, essential fatty acids, vitamins, and minerals per kilocalorie when compared to a maintenance diet. Therapeutic weight loss diets also are lower in energy density, allowing the owner to feed the pet a larger volume of food. Other options include therapeutic “moderate calorie” diets designed for obese-prone patients with other health conditions, as well as over-the-counter weight management diets. These are typically used when the patient has concurrent disease or when the patient is not extremely overweight. Most obese patients require a therapeutic weight loss diet for safe and successful weight loss. The goal is to provide adequate nutrition while restricting calories for weight loss.
Treats can be included in a successful weight loss plan, but should be considered when calculating total caloric intake. Additionally, they should make up no more than five to 10 percent of total calories. Most owners are unaware of the high calorie content in treats, which can make up a significant percentage of calorie intake. Reducing the number of treats, as well as modifying treat type, is usually necessary when designing a weight loss plan.
Monitoring and adjusting the weight loss plan
Patients should be weighed every two weeks during a weight loss plan to allow for safe weight loss at a rate of 0.5 to two percent of body weight per week. If the patient is losing weight too quickly or too slowly, the caloric intake should be adjusted in five to 10 percent increments. Treat intake should be adjusted as well. Based on the rule of thumb that weight loss should occur at 0.5 to two percent of starting body weight per week, the owner can be given a time frame in which weight loss would ideally occur. This can help provide them a sense of perspective and a realistic timeline.
In addition to feeding an appropriate diet for weight loss at an appropriate amount, monitoring patients is essential for success and will also improve client compliance. Once target weight is achieved and the pet is in ideal body condition, the patient should receive an average of five to 10 percent more calories than what was necessary to achieve weight loss to maintain ideal body weight.
This systematic step-by-step approach helps manage many patients, but each pet must be assessed on an individual basis and will require a nutritional plan targeted to its specific needs. Use your nutritional assessment to help discover your patient’s requirements, to understand the owner’s feeding methods and practices, and to help develop the most effective weight loss plans for your patients.
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Catherine Lenox, DVM, DACVN, is a nutritionist with Royal Canin USA. She also teaches online nutrition continuing education through the Veterinary Information Network (VIN). Dr. Lenox can be reached at firstname.lastname@example.org.