QUALITY AND ERGOVALINE CONTENT OF TALL FESCUE SILAGE AS AFFECTED BY HARVEST STAGE AND ADDITION OF POULTRY LITTER AND INOCULUM

Alternative methods of managing endophyte (Acremonium coenophialum)-in fected (EI) tall fescue (Festuca arundinacea Schreb.) are needed to re duce the severity of fescue toxicosis in cattle. Two field experiments were conducted at Fayetteville, AR to determine the effect of adding silage inoculant or poultry litter and harvesting at two maturities on tall fescue silage quality and ergovaline concentration. In Experimen t 1, mature, EI tall fescue (85% of plants infected) was chopped and m ixed with broiler litter at 0, 20, 40, 60, 80, and 100% litter (0, 12, 27, 46, 69, and 100% litter on a dry weight basis). Each mixture was also either inoculated or noninoculated with a mixture of dried fermen tation products of Streptococcus lactus, Lactobacillis caseii, L. plan tarum, and Aspergillus oryzae plus nutrients. Inoculated silage had lo wer (P < 0.01) pH than noninoculated silage except in the 100% litter treatment (inoculation x litter level interaction of P < 0.05). Increa sing proportions of litter increased concentrations of ash, volatile f atty acids (VFA), and nitrogenous compounds and lowered concentrations of neutral detergent fiber (NDF) (P < 0.01). Lactic acid concentratio n was highest (P < 0.01) in silage containing no litter. No nutritiona l advantage to ensiling poultry litter with tall fescue was found. In Experiment 2, El (85% infected) and endophyte-free (EF) tall fescue wa s chopped at the boot stage (24 April) or early mature-seed stage (4 J une) and ensiled for 60 d. Silage from forage harvested at the boot st age had higher (P < 0.05) lactic:butyric acid ratio, and lower (P < 0. 05) pH and butyric acid concentration than silage harvested at the mat ure seed stage. In Experiments 1 and 2, ergovaline concentration of EI fescue was not affected by the ensiling process, but was lower (P < 0 .07) in boot-stage than mature-seed-stage forage. Ensiling allows harv esting of El tall fescue at a relatively early maturity stage, thereby providing higher quality forage with reduced risk of rain damage or e rgovaline toxicity than with harvesting late-maturity tall fescue.