Organ weights and organ:body weight ratios of the African white-tailed rat (Mystromys albicaudatus).

Fifty-three adult female and 51 adult male white-tailed rats (Mystromys albicaudatus) were killed with ether and weighed; the spleen, kidneys, liver, heart, lung, pancreas, brain and gonads were dissected free of adhering tissue and weighted. The mean absolute organ weight and organ:body weight ratios by sex and organ were calculated and compared. The male rats were significantly (p less than or equal to 0.05) heavier. The mean weight of the males was 110.0 +/- 23.8 g versus 82.9 +/- 16.1 g for the females. The absolute weights of the heart, liver and kidneys were significantly (p less than or equal to 0.05) greater for the males. The organ:body weight ratios, except for heart and brain (excluding ovary and testicle), were unaffected by sex. The heart to body weight ratio and the brain to body weight ratio were significantly (p less than or equal to 0.05) larger in female rats.