Page 64 - Small Animal Clinical Nutrition 5th Edition

64 Small Animal Clinical Nutrition

DER, but prolonged exercise can increase energy require-
Box 5-5. Quick Feline Feeding Guide.
VetBooks.ir Unlike dogs, most breeds of cats have a similar body size and ments four- to eightfold over RER. The DER for dogs with
normal activity is 1.6 to 1.8 x RER. This requirement
increases to 2 x RER for dogs doing light work, 3 x RER for
weight (with the exception of certain large breeds like the Maine
coon cat). Therefore, a starting point for feeding cats can be dogs doing moderate work and 4 to 8 x RER for dogs doing
simplified. Assuming the ideal body weight for most cats is heavy work. Many pets, however, are less active than their
approximately 3.6 kg (8 lb) and apply this body weight to the owners perceive. Many pets in the United States may have
equations in Table 5-2. less than “normal activity;” and are overweight and obese
(Chapter 27). Therefore, it may be prudent to start DER cal-
WEIGHT LOSS
culations lower than 1.6 and increase DER if needed to
0.75
Weight loss = 0.8 x RER = 0.8 x (70 x [3.6 ]) = approximate- maintain body condition.
ly 150 kcal/day.*
If a wet food contains 150 kcal/can then offer the cat one THERMOREGULATION
can/day. The influence of housing and climate should not be neglect-
If a dry food contains 450 kcal/cup then offer the cat 1/3 cup ed when evaluating energy requirements.When kept outside in
of food/day.
cold weather, dogs may need 10 to 90% more calories than dur-
ing optimal weather conditions (Table 5-3). Heat losses are
PREVENTION OF WEIGHT GAIN
minimal at a temperature range called the thermoneutral zone.
Weight prevention (inactive/obese-prone cats) = 1.0 x RER = The environmental temperature range at which dogs reach
0.75
1.0 x (70 x [3.6 ]) = offer the cat approximately 180 kcal/day. their minimum metabolic rate is breed specific and is lower
If a wet food contains 150 kcal/can then offer the cat 1 and 1/5 when the thermic insulation (e.g., coat density and length, skin
cans/day. insulation) is better (Kleiber, 1961; Männer, 1991; Meyer,
If a dry food contains 450 kcal/cup then offer the cat 2/5 cup 1983, 1990; Zentek and Meyer, 1992).The thermoneutral zone
of food/day.
was estimated at 15 to 20°C for longhaired and 20 to 25°C for
FEEDING FOR MAINTENANCE shorthaired breeds (Kleiber, 1961; Männer, 1991; Meyer, 1983,
1990). For Alaskan sled dogs, it may be as low as 10 to 15°C
Maintenance = 1.2 x RER = 1.2 x (70 x [3.6 ]) = offer the cat (Meyer, 1983, 1990).
0.75
approximately 200 kcal/day. At temperatures above the thermoneutral zone, energy is
If a wet food contains 150 kcal/can then offer the cat 1 and 1/3 expended to dissipate heat. Conversely, at temperatures below
cans/day.
If a dry food contains 450 kcal/cup then offer the cat 1/3 cup the thermoneutral zone, energy is used to maintain core body
of food per day. temperature. The degree to which environmental temperature
affects energy needs of an animal also depends on air move-
Key: RER = resting energy requirement. ment (wind chill factor), air humidity (Meyer, 1983) and the
*These are starting points and food offerings should be adjust- degree of acclimatization (NRC, 1985). Animal factors includ-
ed to maintain or achieve the desired body weight. ing insulative characteristics of skin and coat (subcutaneous fat,
hair length and coat density) (NRC, 1985; Meyer, 1983; Finke,
1991; Meyer and Heckötter, 1986) and differences in stature,
behavior and activity (Finke, 1991; Meyer and Heckötter,
aging on body composition in Labrador retrievers found that 1986) interact and affect DER.
2
the percentage of fat mass was directly related to age (r = 0.50).
The same study also found that lean body mass was inversely NEUTER STATUS
related to age (r = 0.52) (Harper, 1998a). Because energy There is a paucity of information in the literature regarding
2
requirements are related to lean body mass, reduced activity and the effect of neuter status on energy requirements. Neutering
lean body mass may contribute to reduced energy requirements. (castration, ovariohysterectomy) of animals is thought to be
The reduction in lean mass and increase in fat mass associated associated with the development of obesity because of a com-
with aging could also result from decreased levels of growth bination of factors including reduced activity and changes in
hormone (Harper, 1998a). BER. Data suggest that intact cats have higher energy require-
ments than those that have been neutered (Flynn et al, 1996;
ACTIVITY Root et al, 1996). Neutered cats may be less able to self-regu-
Activity significantly influences energy requirements (i.e., late food intake than intact cats and thus are predisposed to eat
standing up requires 40% more energy than lying down) more food and to become obese (Flynn et al, 1996).
(Meyer, 1983), yet recommendations for MER do not always In dogs, it is unknown whether increases in body weight after
mention the degree of activity included. Most of the dispar- neutering result from increases in appetite and thus food intake
ities in the literature for MER and RER are attributed to dif- or a reduction in energy expenditure or both. In a study of six
ferent activity levels of animals studied. Short bouts of dogs, the fasting energy expenditure was reduced from 37.1
intense physical exercise may cause only small increases in kcal/BW /day (155 kJ) to 33.9 (142 kJ) and 35.3 (148 kJ) at
kg