Major trace elements limiting livestock performance in New Zealand

Abstract

Extract

• Many New Zealand soils are naturally deficient in cobalt and/or selenium and/or copper, or are naturally high in molybdenum. livestock grazing pasture grown on such soils may be deficient in one or more of these trace elements.

• In the 1940s and 1950s, New Zealand researchers were at the forefront of research to define the cause of trace-element related ill-thrift and clinical diseases like white muscle disease, peat scours and enzootic ataxia.

• New Zealanders have devised production-related reference ranges for blood and liver copper, vitamin B₁₂ and selenium that are used for the diagnosis and prevention of deficiencies.

• A range of supplementation procedures has been devised, from topdressing or spraying pasture to direct animal supplementation, to suit the range of livestock management systems found in New Zealand.

• Trace-element monitoring programmes are now a routine procedure for farmers grazing cattle, sheep, and deer on trace-element deficient land.

• Copper deficiency is the main trace-element deficiency diagnosed in deer.