Temporal changes in metabolic rate following a meal
The metabolic rate increased by an average of 21.4% 30 min following a meal, continued to increase to a maximum of 33.2% observed at 60 min, and then decreased towards the basal value (Figure 1).
Figure 1: Oxygen consumption in relation to time since last feed. The symbols represent the different individuals and the colours the energy intakes. Based on the mean oxygen consumption acrosseach time point, the black line represents the predicted rate of oxygen consumption across time.
| Time since last feed (min) | Mean % increase over BMR |
| 30 | 21.39 |
| 60 | 33.2 |
| 90 | 30.68 |
| 120 | 26.95 |
Metabolic responses to varying energy intake levels
The relative increase in metabolism for each energy intake group varied between 31-61%.
| Energy intake (kcal) | HIF (L O2 min-1) | HIF % increase in metabolism over BMR |
| 2658 (5) | 0.3 ± 0.18 | 41.19± 22.61 |
| 2221 (1) | 0.36 | 40.45 |
| 1798 (3) | 0.26± 0.07 | 31.54 ± 2.84 |
| 1659 (1) | 0.33 | 61.11 |
| Mean | 0.31 | 43.57 |
Generalized additive model
The results of the model showed statistical significance for the time after feeding and the random effect of the animal, whereas the rest of the parameters i.e., energy intake, age, body mass, pool temperature were not statistically significant.
Figure 2: Partial effects of the predictor variables of the generalized additive model