title: Some problems in assessing the physiological and economic significance of hypocupraemia in beef suckler herds.
abstract: Factors influencing the incidence of hypocupraemia and responses to copper therapy were investigated in three beef suckler herds calving in spring and early summer. On farm A hypocupraemia was most severe (plasma copper less than 0.4 mg per litre) in March for the cows and in October/November for their calves. On farm B plasma copper levels were 30 per cent lower in five to eight-year-old cows than in two-year-old cows in late November. Administration of copper (100 mg) in late pregnancy significantly increased plasma copper in the suckled calves on farm A but not in their dams after parturition. Growth of the calves was not increased. The alleviation of severe hypocupraemia on a third farm (C) by injecting the calf with copper did not improve growth rate. It is concluded that in some areas a severe seasonal hypocupraemia may be tolerated without loss of productivity.
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D002417:Cattle / Q000254:growth & development*; D002418:Cattle Diseases / Q000097:blood / Q000191:economics*; D003300:Copper / Q000008:administration & dosage / Q000097:blood / Q000172:deficiency*; D005260:Female; D008297:Male; D011247:Pregnancy; D012621:Seasons; D012987:Soil / Q000032:analysis
chemical_list: D012987:Soil; D003300:Copper