[Fe-, Cu-, Zn-, Ni- and Mn-concentrations in sow's milk during a five-week lactation period].

In a trial with 18 sows of the German landrace in three groups the dietary copper supply was varied in gravidity and lactation. Iron, copper, zinc, nickel and manganese concentration of milk was measured on 11 different days during the five weeks' lactation period in response to alimentary copper supply. Copper supply did not influence iron, zinc, and manganese concentration even if it was deficient during gravidity and lactation. Mature sow's milk contained 1.2 micrograms Fe, 1.5 micrograms Cu, 6-8 micrograms Zn, 0.16-0.23 microgram Ni and 0.07-0.13 microgram Mn per g fresh milk. First colostrum contained higher copper and zinc concentrations and lower concentrations of nickel and manganese compared to mature milk. Fe concentration remained constant. This investigation reproduced and completed thereby previous results. It was concluded that in copper deficiency status the interactions of copper with iron, zinc, nickel and manganese may not be effective for the excretion pathway milk.