Starch Disappearance from Different Segments of the Digestive Tract of Steers

Abstract

Eight yearling Angus steers fitted with ruminal and either abomasal or posterior ileal fistulas were fed ground mixed rations containing 19 to 63.5% starch to study its disappearance during passage through different sections of the ruminant gastrointestinal tract. The quantity of starch passing into the abomasum (16 to 38%) increased with increasing starch intake. Thus, postruminal starch digestion assumed a greater role in the overall utilization of starch as dietary starch intake increased. The data suggest that more starch may reach the small intestine than can be digested in this section of the digestive tract of yearling steers fed high-concentrate rations.