The goal of the research is to protect consumers from chemical residues potentially present in food animals. Specifically, the objectives of this research are to determine if ergopeptine is responsible for illness observed in animals associated with fescue toxicosis, assess whether ergopeptine residues are a risk, determine if market animals have illegal residue levels of phenylbutazone, and develop methods to allow the rapid detection of illegal levels of or unsafe drug residues.
Radiolabelled beta-agonists or ergopeptine alkaloids will be used to provide quantitative metabolic fate information. The distribution of the beta-agonist or ergopeptine alkaloids and their metabolites after exposure of an animal to a radiolabelled beta-agonist or ergopeptine alkaloid will be determined by radioassay. The radioactive compounds present in tissues and excreta will be isolated by appropriate extraction and chromatographic procedures. Isolated radiolabelled compounds will be characterized by mass spectrometry, nuclear resonance spectrometry and infrared spectrometry and structures will be confirmed by synthesis if possible. FSIS and FDA will be consulted with respect to choice of the specific beta-agonist studied. FSIS has indicated that clenbuterol is an extremely high priority beta-agonist to be investigated. Salbutamol and zilpaterol are also beta-agonists of interest. Ergovalvine has been chosen as the first ergopeptine to be studied.