Yield, Digestibility, and Chemical Composition of Endophyte Free and Infected Tall Fescue

Publisher Website
Google Scholar
Abstract
Utilization of low‐endophyte (Acremonium coenophialum Morgan‐Jones and Gams) cultivars of tall fescue (Festuca arundinacea Schreb.) has been shown to improve animal performance; however, insufficient information is available on the direct effects of endophyte infection on the productivity and composition of tall fescue herbage. A 2‐yr field study was conducted to assess the effects of A. coenophialum infection on the yield, digestibility, and chemical composition of tall fescue. Endophyte‐free (EF) and endophyte‐infected (EI) plots for each of two tall fescue cultivars (Kenhy and Kentucky 31) were established in August 1985 on a Maury silt loam (fine, mixed, mesic Typic Paleudalt) soil. Dry matter yields were determined for three harvests made in 1986 and 1987. Total N, fiber composition, and in vitro rate and extent of neutral detergent fiber (NDF) digestion were determined on samples of first and second harvest forage. Dry matter yields were not affected by infection status and averaged 0.80 and 0.83 Mg ha−1 in 1986 and 1.69 and 1.79 Mg ha−1 in 1987 for EF and EI tall fescue, respectively. Endophyte infection status had no effect on the rate or extent of NDF digestion. Rate of NDF digestion averaged 0.056 and 0.055 h−1 for EF and El tall fescue, respectively. Endophytic infection also had no influence on the N concentration or fiber composition of tall fescue. The results of this study suggests that A. coenophialum does not have a significant effect on the digestibility or chemical composition of tall fescue.