Two experiments were conducted. Experiment 1 used 2 cohorts each of HAP2 and LAP2 mice, and Experiment 2 used 1 cohort each of HAP1 and HS/Ibg mice. In both experiments, both lines of mice were tested concurrently. In Experiment 1, the first cohort of mice were 12 HAP2 and 12 LAP2, (generation 23) 6 male and 6 female of each line, and were an average of 110 ± 25 days old at the beginning of shaping. The second cohort were 12 HAP2 and 12 LAP2 (generation 24) 6 male and 6 female of each line, and were an average of 137 ± 3 days old at the beginning of shaping. Experiment 2 used 1 cohort of 24 HAP1 (generation 34) and 24 HS/Ibg (generation 76), 12 males and 12 females of each line, which were 70 ± 4 days old at the beginning of the experiment.
