Hunger and food interest assessment.

Setups (A) and performance in the two consumption tests during the first (B), second (C) and third test session (D), with the different food deprivation levels stated in the title of each figure panel. The time needed to eat 100 reward pellets and the time spent exploring in the reward pellet consumption setup, are displayed in the top left and right graphs of each panel, respectively. The bottom graph of each panel shows the cumulative food consumed per rat during the regular food consumption test. Scatter plots for reward pellet consumption test results indicate individual values and group mean. Line graphs for regular food consumption indicate group mean plus standard error of the mean. Statistical test results are given inside the graphs. For the regular food consumption test, two-way ANOVA results are displayed in the bottom right corner, and results from post-hoc analysis are shown for individual data points. Significant genotype differences are indicated by (p<0.05) *, (p<0.01) **, (p<0.001) *** and (p<0.0001) ****.