Effect of White Rice, Brown Rice and New Enriched Rice Diets on Growth, Amount of Voluntary Exercise and Swimming Endurance Time in Rats

Abstract

Effects of white, brown and new enriched rice diets on growth, amount of voluntary exercise and swimming endurance time were compared in rats. Main results were as follows:
1) The final body weight was heaviest in the group fed new enriched rice and lightest in the white rice group with significant differences. The body length showed the same tendency as the body weight, but there were no significant differences in the tail length.
2) Food intake in the white rice group was significantly less than the other two groups during the most of the experimental period. Food intake in the new enriched rice group tended to be larger than in the brown rice group after 42nd day, but the difference was not significant
3) Apparent digestibility of protein in the brown rice group was significantly lower than in the other two groups. There was no significant difference between the white rice and the new enriched rice groups.
4) Amount of voluntary exercise was significantly less in the white rice group than in the other groups after 59th day. The amount in the brown rice group was less than in the new enriched rice group after 63rd day, but not significantly so.
5) Swimming endurance time was shorter in the white rice group than in others. No significant difference was found between the brown rice group and the new enriched rice group.
6) No significant differences were found in the total cholesterol level in the serum of three groups. Urinary excretion of vitamin B₁ and B₂ were in the following order; new enriched rice group>brown rice group>white rice group with significant difference.