Justin Shmalberg, DVM, Diplomate ACVN
To ensure weight loss in obese pets, veterinarians must provide sound information and guidance to owners. The following guidelines can be used to formulate successful treatment plans.
1. Calculate body condition score (BCS); then ideal body weight (BW).
- Follow the BCS definitions closely as it is an objective system.
- Dogs: See Table 1
- Cats: Use BCS or use the estimate that most cats should weigh between 3 to 5 kg.
2. Calculate estimated caloric intake for weight loss.
- Dogs: (50 to 70) × (ideal BW in kg)0.75 = kcal/day
- Cats: (30 to 40) × (ideal BW in kg) = kcal/day
- A 1/3 reduction of a known weight-stable caloric intake is also generally effective.
3. Select a diet with elevated protein levels and reduced caloric density.
- Dogs: Protein > 90 g/1000 kcal
- Cats: Protein > 120 g/1000 kcal
- If the food volume is significantly reduced, diets with < 300 calories/cup and 25 calories/ounce (canned) may reduce food-seeking behavior in dogs and cats.
- Canned diets should be considered in cats based on the available literature, which suggests these diets assist with increased weight loss and decreased rebound weight gain.
4. Provide specific feeding instructions to owners.
- Ask owners to describe how they measure food; ideally, provide an appropriate measuring cup.
- Encourage owners to measure food by weight instead of volume, especially when amounts are small, to maintain consistent caloric intake. Clients can purchase inexpensive digital kitchen scales, or they can be loaned to clients to improve compliance.
- Include treats in the weight-loss plan to increase owner compliance, reducing intake of food appropriately; treats should provide ≤ 10% of daily caloric intake. If the caloric content of a treat is unknown, a value of 4 kcal/g can be used.
- Advise the owner that feeding the recommended daily amount of food in multiple small meals may reduce food-seeking behavior, and has been associated with increased daily energy expenditure.
5. Patients should return for frequent observation and weight-loss plan adjustments.
- Adjust caloric intake weekly or every other week, following a weight check-in.
- Recommended target rates of weight loss are 0.5% to 2% of BW weekly (2%–8%/month).
- Weight loss rates may be higher than desired for the first month; however, do not increase caloric intake as the rate typically slows as weight loss progresses.
- During follow-up visits, reinforce weight-loss goals with the client. Photographic evidence of the pet’s progression can help maintain owner commitment.
6. Routine monitoring is required after achieving weight-loss goals.
- Rebound weight gain is common. Counsel owners that long-term dietary modification is required for weight maintenance.
- Previously obese animals likely benefit from long-term feeding of reduced-calorie, high-protein diets to prevent weight gain.
- Provide honest BCS assessments to owners at each examination.
For help in selecting the right diet, read Beyond the Guaranteed Analysis: Comparing Pet Foods (January/February 2013).
Technicians are well positioned to help manage the obese patient, which is emphasized in the Today’s Technician article, Developing a Nutrition Program in Your Practice (July/August 2012).