Toxicologic studies in growing sheep fed silage corn cultured on municipal sludge‐amended acid subsoil

Field corn was grown on subsoil, pH 5.5, that had been amended with 100 dry tons per acre (224 metric tons per hectare) of municipal sewage sludge from Syracuse, New York. The corn plants containing 3.88 ppm dry weight of cadmium were field-chopped and ensiled, and the silage was fed to growing sheep for 225 d. The sheep fed the sludge-grown corn silage showed a significantly (10 higher feed efficiency, (2) higher hepatic microsomal p-nitroanisole O-demethylase activity, and (3) higher concentrations of cadmium in liver and kidney and nickel in kidney as compared to the control animals. No significant treatment effects were observed in mutagenic responses for animal feed or feces samples. No consistent treatment effects were noted during histopathologic examination of sheep tissues.