28 March 1997

Dont overdo Mg

EWES in late pregnancy should not be fed too much magnesium before lambing and turn-out.

ADAS nutritionist Pete Kelly reports that many ewes near lambing are suffering calcium deficiency due to over feeding magnesium.

"Avoid offering free access minerals or feed blocks high in magnesium to ewes in late pregnancy." The excess magnesium interferes with calcium mobilisation and can cause calcium deficiency, he says. Ewes have twitchy ears and go off their legs.

He suggests such ewes should respond within 10 minutes to an injection of calcium under the skin.

Once lambed and turned out, however, ewes will need extra magnesium to avoid staggers, he says.

"Where grazing conditions are quite dry, producers could add magnesium chloride to drinking water. But when sheep are drinking from streams or conditions are wet, offer magnesium through a concentrate or mix calcined magnesite with maize gluten." &#42