Studies on the starch values of swedes, fodder beet and grass silage and on the complementary value of grass silage and roots when fed together to ruminants

1. Two digestibility trials were carried out to determine the s.e. and t.d.n. of swedes, fodder beet and grass silage when fed alone and when each kind of root was fed with silage at separate feeds. In addition, fodder beet and silage were fed together at the same feed. 2. The results were examined to determine if the feeding of roots and silage together in the diet, but at separate feeds, had led to any complementary effect. 3. No complementary effect was found when swedes and silage were fed at separate feeds. 4. A negative complementary effect was found when fodder beet and silage were fed at separate feeds. 5. The s.e. and t.d.n. values of the fodder beet plus silage at each feed were significantly higher than when the two foods were given at separate feed times. 6. The s.e. and t.d.n. of the swede dry matter were higher than the standard figures published. An explanation is given. 7. The nutritive value of the fodder-beet dry matter was not higher than that of swede dry matter. 8. The results of the digestibility trials are compared with some calculated results from a cattle feeding trial.