Fig. 1.

Average daily litter gain (ADG) and pup survival among 32 inbred mouse strains. Females from each strain were studied in their 2nd lactation. Females were induced to ovulation by treatment with PMS and HCG and then mated to CD-1 males. On day 1 postpartum, number of pups born per litter was recorded and independent cross-foster litters of 10 1-day-old CD-1 pups were then given to each dam. ADG weight gain (A) and maternal litter rearing capacity (B) were recorded daily through day 8 postpartum (PNUM8). Each symbol represents the mean ± 95% confidence interval (CI) for 8–16 dams with the exception of CAST/EiJ for which only a single dam was obtained. Numbers in parentheses indicate the number of animals studied. The solid gray lines indicate the 95% CIs about the overall mean for each trait. Symbols are color coded by the percentile ranking of the strain mean for ADG.