Cobalt is an essential ingredient for healthy sheep

COBALT is essential for health, because it is converted to vitamin B12 in the rumen and a lack of it suppresses appetite, resulting in what is often recognised as ‘pine’ and significant lack of growth.

Mrs Dun said affected lambs often developed an open, ‘starey’ coat and sometimes tear staining down the face, caused by mild conjunctivitis.

“The cobalt requirement of sucking lambs is low but once they start to eat grass their requirement becomes high, with sheep having higher cobalt requirements than cattle,” said Mrs Dun.

Soils derived from acidic igneous rock are low in cobalt, and most incidences of cobalt deficiency are found in parts of Scotland, Northumbria, Devon and North Wales.

“Other applications of nutrients to the land, in particular iron, manganese and/or nitrogen can restrict the uptake of cobalt in the pasture, as can high soil pH levels,” she said.

“If your stock had a cobalt deficiency in previous years and your pasture management is similar, the problem may continue.

“Once your vet has, through assessing vitamin B12 levels, identified a cobalt deficiency, short term solutions, lasting three to four weeks, are cobalt sulphate drenches or appetite stimulation with injections of vitamin B12.

“Boluses, with nine to 12 months protection, offer a longer term solution.”

Mrs Dun said cobalt sulphate could be sprayed onto the land, but this was expensive. Cattle mineral tubs which include cobalt, but also high levels of copper, can be dangerous to sheep, and their use should be avoided.