Page 525 - Small Animal Clinical Nutrition 5th Edition

Obesity 541

VetBooks.ir CASE 27-4

Weight Loss in a Domestic Shorthair Cat
Philip Roudebush, DVM, Dipl. ACVIM (Small Animal Internal Medicine)
Hill’s Scientific Affairs
Topeka, Kansas, USA

William D. Schoenherr, PhD
Hill’s Pet Nutrition Center
Topeka, Kansas, USA

Patient Assessment
A 10-year-old, neutered female domestic shorthair cat was examined for routine geriatric health maintenance.The patient weighed
4.8 kg and its ribs were very difficult to feel under a thick fat cover. A moderate-to-thick fat layer covered bony prominences. The
cat’s abdomen was pendulous with no obvious waist. A marked abdominal fat pad was present and the cat’s back was broadened
when viewed from above. The cat’s limbs also had fat deposits. Results of a complete blood count, serum biochemistry profile and
urinalysis were normal.

Assess the Food and Feeding Method
The cat was fed a dry, specialty brand adult cat food free choice and was given one can of moist, grocery store brand cat food twice
weekly as a treat.

Questions
1. What is the body condition score (BCS) for this patient?
2. What are risk factors for obesity in cats?
3. What types of therapeutic foods are available to help manage overweight or obese cats?
4. Are there clinical studies supporting the use of therapeutic foods for effective weight loss in cats?

Answers and Discussion
1. The physical examination findings support a diagnosis of obesity (BCS 5/5).
2. This cat has several risk factors for obesity. Middle-aged and older cats are more prone to obesity than younger animals. Female
cats are at higher risk than male cats. Neutered cats are at greater risk than intact animals. Studies have shown that neutered cats
require up to 30% fewer calories per day than before they were neutered. Strictly indoor cats usually are less active.
3. Traditional methods of weight management include use of low-calorie, high-fiber foods. Added fiber increases bulk and reduces
hunger, while diluting calories.Weight-management foods often contain added L-carnitine, which helps cats lose fat safely, while
maintaining lean body mass. An alternative weight-management concept for cats includes using a low-carbohydrate, high-pro-
tein food to alter a cat’s metabolism for effective weight loss. When carbohydrates are unavailable, the body burns body fat and
dietary protein as energy sources. When fed this type of food, cats lose weight and have improved glucose and lipid control. Food
choice is based on veterinarian discretion and response to previous weight-management programs. Regardless of the food cho-
sen, caloric restriction should be instituted and the amount of food fed should be closely monitored.
4. A study was conducted in which middle-aged or senior domestic shorthair cats with more than 30% body fat were fed either a
a
low-calorie, high-fiber formula (Prescription Diet r/d Feline ) or a low-carbohydrate, high-protein formula (Prescription Diet
a
m/d Feline ) for 24 weeks. Cats were fed to achieve ideal body weight and condition, which typically means 20% body fat. Each
cat was fed its assigned food until it achieved 20% body fat or completed the 24-week study. More than 70% of each group
reached ideal body weight within 20 weeks. Weight loss was well within the 0.5 to 2% of initial body weight per week recom-
mended for safe weight loss by veterinary nutritionists. Importantly, both groups maintained lean body mass.
After two months of feeding, cats fed the moist, low-carbohydrate, high-protein formula had twice the levels of beta-hydroxy-
butyrate (a ketone) as cats fed the moist, low-calorie, high-fiber formula.This finding signals a metabolic shift from using dietary
carbohydrates to body fat as a primary energy source.These metabolic changes contributed to the weight loss in cats fed the low-
carbohydrate, high-protein formula. Biochemistry profile data indicated no abnormal changes in organ function in either study
group. Both the traditional, low-calorie, high-fiber food, and the low-carbohydrate, high-protein, metabolic control food, were
safe and effective for weight loss in cats.

Progress Notes
The cat was fed a dry, low-carbohydrate, high-protein food (Prescription Diet m/d Feline) to help achieve weight loss.The amount
of food was calculated based on an ideal body weight of 3.41 kg (daily energy requirement for weight loss = 0.8 x resting energy