EFFICACY OF COPPER-OXIDE WIRE SUPPLEMENTATION ON REPLETION OF COPPER STORES IN RANGE BEEF-CATTLE IN NORTHERN CALIFORNIA

A field study was conducted to determine effects of copper oxide wire supplementation on serum and liver copper concentration in range beef cows diagnosed with copper deficiency. Cows were supplemented with one 25-g copper oxide wire capsule (N = 39) or left unsupplemented (N = 1 25). All cattle were vaccinated with a commercial clostridial vaccine before supplementation to ensure adequate titers to these antigens bef ore liver biopsy. Cows were bled before and 45 days, 4, 6, and 8 month s after supplementation. Liver biopsies were collected 4, 6, and 8 mon ths after supplementation. It was found that range beef cattle can be supplemented safely with a single dose of copper oxide needles (25 g) and may have higher liver copper concentrations than control cattle 8 months after supplementation.