Page 106 - Raw Diet References Book 2019

2.2.9 Analytical determination

Prepared samples shall be used for analysis. AOAC is not collected, food and faeces also shall be assayed
approved analytical methodology shall be used for crude protein.
when available or one of the methods p.
If digestibility values of dry matter, fat or other
Food, faeces and urine (if collected) shall be nutrients are wanted, food and faeces should also be
assayed for gross energy (bomb calorimetry). If urine assayed for those substances.

2.2.10 Calculation of digestible energy and digestible nutrients

The determination is based on assays of the gross energy consumed minus the energy in the faeces.

(GE of food consumed - GE of faeces collected)
DE (per g food) =
amount of food consumed

(CP of food consumed - CP of faeces collected) x100
DP (% of food) =
amount of food consumed

Digestible fat, ash and dry matter can be calculated in the same way as digestible protein.

2.2.11 Calculation of metabolizable energy

The determination is based on assays of the gross correction for energy lost in the urine (or energy lost
energy consumed minus the energy in the faeces and in urine as determined by calorimetry).

Without urine collection

[(GE of food consumed - GE of faeces collected) -
(grams protein consumed - grams protein in faeces) x
ME = correction factor for energy loss in urine]

amount of food consumed

Correction factor for energy lost in urine (Kienzle 1.25kcal or 5.23kJ/g for dogs
et al. 1998): 0.86kcal or 3.60kJ/g for cats

Example:

a. gross energy of food .........................................................= 4.35kcal/g or 18.2kJ/g
b. amount of food consumed .............................................= 1250g
c. gross energy of faeces .....................................................= 1.65kcal/g or 6.90kJ/g
d. amount of faeces collected ............................................= 600g
e. protein in food ...................................................................= 24%
f. protein in faeces ................................................................= 9%
g. correction factor (dog) .....................................................= 1.25kcal/g or 5.23kJ/g

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