EVALUATION OF CLINICOPATHOLOGICAL PARAMETERS IN CATTLE GRAZING TIMBERMILKVETCH

The purpose of this study was to determine whether hematological and s erum biochemical parameters could be used to diagnose poisoning in cat tle grazing timber milkvetch (Astragalus miser var. serotinus), a nitr opropanol-containing legume. Blood samples were obtained from 20 Heref ord cattle on timber milkvetch range in southern British Columbia duri ng 1992 and 1993. Relevant changes in blood parameters were not detect ed and the parameters could not be used to predict nitropropanol inges tion or intoxication. The same parameters were measured in dosing tria ls with cattle with rumen fistulas, but relevant changes were not dete cted. Succinate dehydrogenase is the key target in nitropropanol intox ication and an assay for this enzyme may provide a probe for diagnosis .