Dry Matter Intake and Digestibility of ‘Coastal’, ‘Tifton 44’, and ‘Tifton 85’ Bermudagrass Hays Grown in the U.S. Upper South

Abstract

ABSTRACT‘Coastal’ bermudagrass [Cynodon dactylon (Pers.) L.] is the major warm‐season grass grown across the U.S. upper south. More recent hybrids of ‘Tifton 44’ (T44) and ‘Tifton 85’ (T85) (Cynodon sp.) offer improved nutritive value. Compared are dry matter (DM) intake and digestion of Coastal bermudagrass (CB), T44, and T85 hays grown under different soil and climate conditions and harvested at either the same or different maturities. In the comparison of CB and T44 with steers (Bos taurus L.), DM intake was greater for CB in one of three experiments, whereas intakes did not differ in the other two. Greater intake for CB was associated with greater DM digestion. In the other two experiments, T44 had greater DM digestion than did CB in one trial but did not differ in the other. Hays of CB, T44, and T85, harvested in 2 yr, were compared by means of sheep (Ovis aries L.). In Year 1, sheep consumed more CB than either T44 or T85, whereas in Year 2, no differences in intake were detected. Coastal was digested least in both experiments compared with T44 and T85, and T85 had greatest DM digestion in one of the two years. Samples of masticate of CB had the least in vitro true dry matter disappearance (IVTDMD) with T44 intermediate and T85 generally greatest. In general, animal response data showed little advantage of T44 in comparison with CB; however, Tifton 85 appears to have greater digestible fiber and offers potentially greater DM digestion and digestible intake compared with CB.