Body fat measurement system

1. A method for determining the percentage body fat of a four legged domestic pet mammal, comprising the steps of:

measuring a first body dimension having a high correlation with percentage body fat;

measuring a second body dimension having a low correlation with percentage body fat; and

determining the percentage body fat from a relationship between only the first and second body measurements and the percentage body fat using a body fat look-up table comprising a first storage area for storing therein entries of the first body dimension, a second storage area storing therein entries of the second body dimension and an output storage area storing an indication of the percentage body fat.

2. A method according to claim 1 , wherein the first body measurement is the circumference of the ribcage, taken at the 9 th rib.

3. A method according to claim 1 , wherein the second body measurement is a leg index measurement, which is the length of the hind limb measured between the patella (knee) and the calcaneal tuber (hock).

4. A method according to claim 1 , wherein the output storage area provides an indication of whether the mammal is under, normal or overweight.

5. A method according to claim 1 , wherein the output storage area provides a numerical percentage body fat.

6. A method according to claim 1 , wherein the relationship between the percentage body fat and first and second body dimension is given by the equation:

PercentageBodyFat

=

[

(

R

C

1

-

L

)

C

2

]

-

L

where

R=ribcage circumference

L=leg index measurement

C1=constant

C2=constant.

7. A method according to claim 1 , wherein the four legged mammal is a cat.

8. A method according to claim 1 , comprising the further step of determining a target body weight from a relationship between the percentage body fat, a body weight and the target body weight using a look-up table comprising a first storage area for storing entries of the percentage body fat, a second storage area for storing entries of body weight, and an output storage area storing an indication of the target body weight.

9. A method according to claim 8 , wherein the relationship between the target weight, the body weight and the percentage body fat is given by the equation:

Target weight=1.33×Body weight (kg)×((100−% body fat)/100).

10. A method according to claim 8 , wherein the target weight is an ideal weight.

11. A method according to claim 8 , further comprising the step of determining an energy allowance.

12. A method according to claim 11 , wherein the energy allowance is a daily allowance in kcal/kg.