EVALUATION OF INTRARUMINAL DEVICES FOR COMBINED FACIAL ECZEMA CONTROLAND TRACE-ELEMENT SUPPLEMENTATION IN SHEEP

Intraruminal devices containing zinc oxide are very effective in preve nting facial eczema in sheep. In the present study, such devices augme nted with various amounts of selenium and cobalt have been evaluated f or their ability to improve the Se and Co status of pregnant ewes, as reflected by changes in blood Se and serum Vitamin B-12 concentrations . Devices containing 16.4 mg of Se (as sodium selenate) and 20.4 mg of Co (as cobalt sulphate) were effective in increasing and maintaining elevated blood Se concentrations for at least 84 days and serum Vitami n B-12 for 42 days. Such devices will therefore prevent trace element deficiencies in sheep as well as providing protection against facial e czema.