CADMIUM CONCENTRATIONS IN KIDNEYS OF SHEEP AND CATTLE IN WESTERN-AUSTRALIA .1. REGIONAL DISTRIBUTION

A sample of 4973 kidneys from sheep stratified by age and shire of origin within the Agricultural Region Of Western Australia, was analysed for cadmium (Cd) content during the period August 1989 to April 1991. The geometric mean Cd concentration in the kidney of hogget ewes was 0.9 mg/kg, in 4-tooth ewes 1.47 mg/kg and in adult ewes 3.34 mg/kg on a wet weight basis. The mean Cd concentrations of either ewe or hogget flocks from different Divisions of the Agricultural Region did not differ from each other. The annual increase in Cd concentration of kidney from hogget sheep was estimated to be 0.65 mg/kg. The rate of accumulation of Cd in kidney from cattle and sheep grazing the same properties was similar. Kidneys from a sample of 354 adult cattle from the Kimberley Region and 483 aged sheep from the Pastoral Region, both areas of unimproved rangelands, had geometric mean Cd concentrations of 0.15 mg/kg and 0.31 mg/kg respectively. A higher Cd concentration in flocks from the divisions adjacent to the Agricultural Region may have resulted from the establishment of some volunteer species of winter annual pastures in the rangeland.