Mineral deficiencies

The most common mineral deficiencies in cattle, sheep and goats in Australia are of copper, selenium, cobalt and phosphorus.

Conditions when mineral deficiencies are likely to occur

Copper deficiency

• known deficient areas such as coastal sandy soils, granite soils and peat swamps. Deficiency is made worse by excess molybdenum or lime application
• extended periods on green feed as copper is more available in dry feed
• breeding stock
• growing stock.

Selenium deficiency

• known deficient areas such as coastal sandy soils, acidic soils, sedimentary and granite soils, usually in high rainfall regions. Deficiency is made worse by high superphosphate application and clover dominance
• lush feed situations
• young growing stock.

Cobalt deficiency

• known deficient areas such as coastal calcareous sands, high rainfall granite soils and krasnozem soils. Deficiency is made worse by lime application and high superphosphate application, especially in lush seasons
• young growing stock.

Phosphorus deficiency

• history of very limited superphosphate application on soils naturally deficient in phosphorus
• lactating cows
• young growing cattle.

Identification and diagnosis

Clinical signs that would lead you to suspect a mineral deficiency include the following:

• copper deficiency – rough coat, faded coat (e.g. sandy-colour Hereford or bronze-tinged Angus), poor growth and diarrhoea
• selenium deficiency – stiff-legged gait, poor growth and sudden death
• cobalt deficiency – ill-thrift and emaciation
• phosphorus deficiency – pica (eating bones and other rubbish), poor growth, soft bones and fractures, infertility and post-calving red water.

Pasture samples, soil samples and blood samples from affected animals can also be useful in the diagnosis of mineral deficiencies. Clinical response-to-treatment trials can also assist.

Prevention

An integrated approach to prevent mineral deficiencies should consider the following:

• supplementing minerals via injections, capsules, drenches, pellets, pour-ons or as loose licks
• top-dressing pastures.