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.