[Copper and zinc contents in milk and plasma of cows after high nutritional copper supplements].
In three feeding trials with dairy cows over periods of six weeks each, it was studied whether very high nutritional supplements of copper alter the copper and zinc levels of milk and plasma. The supplemented groups with an average milk yield of 20 kg were given CuSO4 X 5H2O at levels varying from 250 to 550 mg copper per cow and day over and above the amount supplied by the commercial winter ration (300 mg copper and 1200 mg zinc). There was no significant influence of the copper supplementation on the copper and zinc contents of milk compared with the untreated control animals. On the average for all experimental weeks, copper contents of 0.15--0.20 mg and zinc content of 4.0--4.6 mg/kg milk were recorded for the various experimental groups. The mean copper contents in plasma varied from 1.00 to 1.18 microgram/ml in the copper-supplemented groups and from 0.93 to 1.09 mircogram/ml in the control groups. The corresponding mean values for zinc ranged from 0.93 to 1.18 microgram/ml. Analysis of variance did not show any significant differences between the experimental groups nor any interactions between the copper and zinc contents. These results were discussed in relation to the dietary supply status.
D000818:Animals; D002417:Cattle; D003300:Copper / Q000032:analysis* / Q000097:blood; D004032:Diet; D005260:Female; D008892:Milk / Q000032:analysis*; D015032:Zinc / Q000032:analysis* / Q000097:blood
D003300:Copper; D015032:Zinc
Kupfer-und Zinkgehalte in der Milch und im Plasma von Kühen nach hoher nutritiver Kupferdosierung.