Table 6. Metabolizable energy (ME; kcal/kg; means and standard deviation, SD), were determined in feline digestibility studies and compared to those calculated using predictive equations.
All Cat Foods | Dry Cat Foods | Canned Cat Foods | ||||
(n = 227 studies) | (n = 173 studies) | (n = 54 studies) | ||||
Mean | SD | Mean | SD | Mean | SD | |
Measured ME | 3369 | 1374 | 4107 | 410 | 1005 | 189 |
Calculated ME using modified Atwater factors a | 3316 | 1288 | 4017 | 306 | 1069 | 153 |
Delta b | −53 | 224 | −90 | 241 | 64 | 81 |
Absolute Delta c | 173 | 151 | 201 | 160 | 83 | 61 |
Calculated ME using NRC predictive equations d | 3308 | 1297 | 4010 | 343 | 1059 | 153 |
Delta b | −61 | 240 | −96 | 261 | 54 | 88 |
Absolute Delta c | 180 | 170 | 210 | 182 | 86 | 55 |
Calculated ME using new predictive equation e | 3369 | 1372 | 4107 | 395 | 1004 | 195 |
Delta b | 0 | 82 | 0 | 90 | −1 | 42 |
Absolute Delta c | 63 | 52 | 71 | 55 | 35 | 29 |
Predicted ME using equation with modified Atwater factors [4].
The difference between measured and estimated ME.
The absolute value of the difference between measured and estimated ME.
Predicted ME using NRC [2] equations.
Predicted ME using equation developed from the experimental animal feeding studies.