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A simple, rapid method of liquid solid extraction coupled with a sensitive HPLC procedure with fluorescence detection to measure ergot alkaloid levels in bovine blood samples is presented. Single injections of either ergosine, ergotamine, or ergine were given to Holstein steer calves (140 kg), and serum concentrations of the ergot alkaloids were monitored over a 2-h period. Serum samples were loaded on a Bond Elut (100 mg) C 18 column that had been washed with methanol and distilled water. Ergot alkaloids were then eluted with methanol and analyzed by HPLC. Recovery of ergosine, when added to serum at concentrations of 0.5-24.0 ng/mL, ranged from 95 to 98%. The data fit previous reports of three phases in elimination of drug. The method reported has excellent repeatability, a detection limit of 0.5 ng/mL, and provides an alternative to quantitate ergosine, ergotamine, and ergine in bovine blood samples at therapeutic dosages.

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Alternative methods of managing endophyte (Acremonium coenophialum)‐infected (EI) tall fescue (Festuca arundinacea Schreb.) are needed to reduce 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 Experiment 1, mature, EI tall fescue (85% of plants infected) was chopped and mixed 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 fermentation products of Streptococcus lactus, Lactobacillis caScii, L. plantarum, and Aspergillus oryzae plus nutrients. Inoculated silage had lower (P < 0.01) pH than noninoculated silage except in the 100% litter treatment (inoculation × litter level interaction of P < 0.05). Increasing proportions of litter increased concentrations of ash, volatile fatty acids (VFA), and nitrogenous compounds and lowered concentrations of neutral detergent fiber (NDF) (P < 0.01). Lactic acid concentration was highest (P < 0.01) in silage containing no litter. No nutritional advantage to ensiling poultry litter with tall fescue was found. In Experiment 2, EI (85% infected) and endophyte‐free (EF) tall fescue was chopped at the boot stage (24 April) or early mature‐seed stage (4 June) and ensiled for 60 d. Silage from forage harvested at the boot stage had higher (P < 0.05) lactic:butyric acid ratio, and lower (P < 0.05) pH and butyric acid concentration than silage harvested at the mature 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 harvesting of EI tall fescue at a relatively early maturity stage, thereby providing higher quality forage with reduced risk of rain damage or ergovaline toxicity than with harvesting late‐maturity tall fescue. Research Question Beef producers in the tall fescue producing region of the southeastern USA usually have difficulty harvesting excess spring growth of tall fescue as hay at the optimum stage for high forage quality because of wet, cool conditions. Producers also often have access to abundant supplies of poultry litter for use as a cheap N fertilizer or animal feed. Making silage is an alternative method of harvesting and preserving excess spring growth of tall fescue and preserving poultry litter; however, little is known of the ensiling characteristics of tall fescue or litter, nor of the fate of toxins associated with the endophyte in tall fescue. Our objectives were to study the silage characteristics of tall fescue‐poultry litter mixes, with or without a silage inoculant, and to compare the forage quality and potential toxicity of early‐ and late‐cut tall fescue for silage. Literature Summary Fescue toxicosis in cattle consuming endophyte‐infected tall...