Trace element status on sheep-beef farms in the Raglan-Franklin districts

Abstract

During spring 1995, pastoral farms in the Raglan- Franklin districts were surveyed to establish their trace element status. The major soil groups of the area were identified and a geographically representative sample of farms within these soil groups sampled for soil and pasture trace element concentrations. In total, 82 sites on 40 farms were sampled. In addition, liver samples from 80 lambs on 20 of these properties were analysed for trace elements during summer of 1995/96. Soil samples were analysed for Mn, Cu and Co; pastures were analysed for Mn, Fe, Zn, Cu, B, Mo, Co, Se and I. Lamb livers were analysed for Cu, Se and vitamin B12. Survey findings indicated that the Co concentrations in soils, pastures and vitamin B12 in lamb livers throughout much of the district were marginal, particularly in the southern area. The two soil groups most at risk were the yellow-brown loams and yellow-brown earths. Farmers are advised to closely monitor their Co status during late spring and to consider their grazing management strategies. Generally, the status of other trace elements was satisfactory. Keywords: lambs, liver vitamin B12, pasture cobalt, soil cobalt, soil contamination, soil group, titanium, trace elements