Demand functions for cage size in rabbits selectively bred for high and low activity in open-field

The H males had the highest intercept and the L males had the lowest intercept and the shallowest slope, however, all the differences in characteristics of the demand functions between lines and sexes were non-significant. There were significant correlations between measures of motivation calculated from the demand function (baseline rate, total number of lever pressess, total cage size achieved, area under the curve, slope, intercept). The motivation for more cage space was negatively correlated with body weight. The percentage of animals that could be conditioned operantly have been suggested as the additional measure of differences in motivation between groups of animals. The results show that operant conditioning and demand function using the settings as in the present experiment could not demonstrate significant differences in motivation for more cage space in rabbits selected divergently for open-field locomotor activity.