Page 499 - Small Animal Clinical Nutrition 5th Edition

Obesity 515

VetBooks.ir Depending on the combination, mixed fibers would be likely to DM protein and 21% DM crude fiber. The two experimental
foods were only slightly different and contained about 33.5%
result in less flatulence than using only soluble fibers and less
fecal volume than using only insoluble fibers. DM protein and about 10.5% DM crude fiber; the soluble
Taken together, study results support the use of dietary fiber fiber fraction was increased vs. the control food. The experi-
in foods intended for weight loss and weight maintenance. For mental foods also had optimized amino acid ratios based in
the reasons noted above, most commercial calorie-restricted part on higher lysine content. Compared to dogs fed the con-
foods with increased fiber contain primarily insoluble fiber. trol food, dogs fed the experimental foods lost significantly
The recommended range for fiber content of dog foods more body weight (-2.1 kg vs. -1.3 kg, respectively) and had
intended for weight loss is between 12 and 25% DM; for pre- better lean body mass responses (approximately +0.3 kg vs. -
vention of weight regain, the range is between 10 to 20% 1.1 kg, respectively) (Yamka et al, 2007b).
DM. The range for dietary fiber content of cat foods used for The lysine content of a food for weight management is not
weight loss is between 15 and 20% DM; for prevention of reflected by crude protein content. Individual ratios of essential
weight regain following weight loss, the range is between 6 amino acids to lysine are useful but are cumbersome to use for
and 15% DM. key nutritional factor targets. Although not an ideal represen-
tation of how “perfect” a food’s protein content is, the total
Protein and Amino Acids amount of lysine in dog foods for weight management is some-
Dietary protein has several effects that benefit weight loss. what indicative. The recommended amount of DM lysine in
Increased dietary protein and amino acids are necessary for dog foods for weight loss is at least 1.7% (Yamka et al, 2007).
animals undergoing a weight-loss regimen to prevent loss of Dietary protein stimulates increased postprandial thermogene-
lean body mass (Hannah and Laflamme, 1998; Bierer and sis and protein turnover. The heat generated during the post-
Bui, 2004; Laflamme and Hannah, 2005). Dog foods for prandial period is approximately 68% greater than that gener-
weight loss should contain at least 25% DM crude protein ated from carbohydrate sources. Therefore, when an animal
(higher is better) to help prevent loss of lean body mass consumes protein, it burns more energy (more heat), which
(Jewell and Toll, 2007). Dog foods intended for prevention of appears to be associated with increased protein turnover
weight regain should contain at least 18% crude protein (increased protein synthesis). Also, the efficiency of the body to
(higher is better). Cat foods for weight loss should contain at convert protein to ATP via oxidation is decreased substantially
least 35% DM crude protein (higher is better) for the same when compared to fat or carbohydrate. Thus, less net energy is
reason.These same values are recommended for prevention of available when animals consume high-protein compared to
weight regain in cats. high-carbohydrate foods (Laflamme and Hannah, 2005).
Not only is the amount of protein important in protecting
against loss of lean body mass during weight loss, so is the Carbohydrates
protein quality (Yamka et al, 2007b). The quality of a protein Carbohydrates are an excellent source of energy in canine and
depends on the makeup of its constituent amino acids. When feline foods. There are three main categories of carbohydrates:
amino acids are used for protein synthesis, each necessary simple sugars, complex carbohydrates and dietary fiber (Flick-
amino acid must be available in adequate amounts. The inger and Sunvold, 2005) (Chapter 5). The importance of
amino acid that is in the shortest supply is referred to as the dietary fiber has been discussed above.
first limiting amino acid. The idea of an ideal or perfect pro- Simple sugars and complex carbohydrates (grain sources)
tein was first established in swine. The purpose of optimizing have received much attention in human nutrition and weight
the amino acid profile of feeds for swine was to maximize lean loss because of their effects on the glycemic index. The
tissue and minimize fat in finished swine carcasses. This glycemic index is a ranking system for carbohydrates based on
required determining the first limiting amino acid, usually their immediate effect on blood glucose levels. Similar to effects
lysine, then balancing the content of the other essential amino in people, consumption of different sugars and carbohydrate
acids in the feed to the lysine content. This resulted in swine sources alters postprandial glucose levels and insulin secretory
feeds with ideal or perfect protein content; protein for which patterns in dogs and cats (Flickinger and Sunvold, 2005;
the potential for amino acid antagonism and imbalances were Bouchard and Sunvold, 2000; Nguyen et al, 1998; Sunvold and
minimized (Chapter 5). The result was a leaner, more readily Bouchard, 1998). As a result, it has been suggested that foods
marketable carcass and more efficient growth. Later, producing low glycemic responses be fed to animals that are
researchers used the same idea for determining the ideal or diabetic, obese and for the prevention of both conditions.
perfect amino acid profile for dogs and cats (Baker and Consumption of foods with a low glycemic index improves
Czarnecki-Mauldin, 1991). blood glucose and lipid control (Nguyen et al, 1998).
The use of this technology in foods for overweight dogs has In a study that evaluated the effects of feeding five different
shown promising results in weight loss and maintenance of carbohydrate sources (corn, wheat, barley, rice and sorghum) on
lean body mass during weight loss. Overweight dogs (>30% glucose and insulin responses in dogs, rice had the highest post-
body fat) were fed either a commercial veterinary therapeutic prandial glycemic response (i.e., increased postprandial glucose
weight-loss food (control food) or two experimental weight- and insulin response). Barley, corn and sorghum were the best
loss foods for two months. The control food provided 28% carbohydrate sources for dogs with impaired glucose control