Effect of endosperm type on the utilization of sorghum grain by beef cattle

Abstract

In vitro evaluation of 61 varieties of sorghum grain indicated definite varietal differences in digestibility. The only factor having a significant influence on in vitro digestibility was seed hardness which is directly related to the endosperm type of the grain. In vivo carbohydrate digestibilities of dry ground grain of four endosperm types (floury, normal, corneous, and waxy) indicated varietal differences. Floury and waxy endosperm grains were most digestible, normal endosperm grain was intermediate, and corneous endosperm grain was least digestible. When floury, waxy, and corneous endosperm grains were reconstituted and ground, the in vivo digestibilities of all endosperm types were statistically equal though floury and waxy endosperm grain tended to be superior to grain with a corneous endosperm. Feeding trials indicated no difference due to endosperm type in average daily grain, dressing percentage, or carcass quality. Tattle receiving mixtures containing floury endosperm grain consumed less dry matter than cattle fed the other endosperm types with waxy endosperm mixtures being consumed, in intermediate amounts. Cattle receiving normal or corneous endosperm grain mixtures consumed the moot: dry matter. In dry ground mixtures, floury endosperm grain had the highest net energy value with normal and waxy endosperm grains intermediate in net energy value. Dry ground corneous endosperm grain had the lowest net energy. Met energy was equal if grain was reconstituted and ground.