a Presumes an energy density of 3.5 kcal ME/g DM, based
on the "modified Atwater" values of 3.5, 8.5, and 3.5 kcal/g
for protein, fat, and carbohydrate (nitrogen-free extract, NFE), respectively.
Rations greater than 4.0 kcal/g should be corrected for energy density;
rations less than 3.5 kcal/g should not be corrected for energy.
b Although a true requirement for fat per se has not been
established, the minimum level was based on recognition of fat as a
source of essential fatty acids, as a carrier of fat-soluble vitamins,
to enhance palatability, and to supply an adequate caloric density.
c Because of very poor bioavailability, iron from carbonate
or oxide sources that are added to the diet should not be considered
as components in meeting the minimum nutrient level.
d Because of very poor bioavailability, copper from oxide
sources that are added to the diet should not be considered as components
in meeting the minimum nutrient level.
e Because processing may destroy up to 90 percent of the
thiamine in the diet, allowance in formulation should be made to ensure
the minimum nutrient level is met after processing.
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