On the last visit of day 1, nevertheless, the difference was not significant anymore. As the food was available during a 20 h period, one may think that a decrease in the freshness of the VPK diet could be involved.
During the last visit of day 2, however, the difference of consumption between the two diets was still observed. If the attraction of the diet decreased with time the effect should have been higher for LPK since the last visits occurred later than during the VPK session on day