A model to predict kidney and liver cadmium concentrations in grazing animals

摘要

Abstract Cadmium (Cd) accumulation in the kidneys and liver of older grazing animals is a major concern in New Zealand and Australian agriculture. Use of phosphate fertilisers containing high Cd concentration is the main cause of this accumulation. A simple mathematical model running in a user‐friendly computer package was developed to predict annual accumulation of Cd in kidneys and liver of animals grazing pastures of known herbage Cd concentration and phosphate fertiliser history. Results from the model showed that kidney and liver Cd concentration of sheep were most sensitive to fertiliser Cd concentration, moderately sensitive to pasture ingestion rate, and least sensitive to soil ingestion rate. The model was validated using kidney Cd data from a farmlet‐scale sheep‐grazing trial. Kidney Cd concentrations predicted by the model were strongly correlated with measured mean kidney Cd concentrations. The relationship between the measured and predicted Cd concentrations is not statistically different fro...