Figure 3.
B6/J mice exhibit seasonal variation in birthrates. A) Mean number of pups per litter from 2006 to 2012. B) Annual variation in birthrates from 2006 to 2012. C) Mean number of progeny per litter for all calendar years from 2006 to 2012. Data were fitted to a third-order polynomial function (R2 = 0.47). D) Monthly number of B6/J mice born per litter differs significant across the year. Significance of observed differences for the monthly number of B6/J mice born per litter was determined by 1-way ANOVA (F = 107.3; P < 0.0001) followed by Dunn’s multiple comparison test with January as reference variable. *P ≤ 0.05; **P ≤ 0.01; ****P < 0.0001.