[The content of Hb in blood and the protein, Fe, Fe-binding capacity, Cu and Zn in blood plasma of low parity sows before and after oral iron administration].

In investigations of 51 pregnant sows, blood Hb levels above 7.45 mmol/l (mean value of 8.94 +/- 0.88) were recorded from 43 animals (Group A), while levels below that margin were recorded from eight (Group B) (mean value of 6.73 +/- 0.31). Iron levels in blood plasma of Group A were 36.9 +/- 8.07 and were thus higher (p less than 0.01) than those in Group B (28.9 +/- 5.19 mumol/l). No difference was found to exist between the two groups with regard to iron fixation capacity as well as copper and zinc in blood plasma. Oral uptake of 50, 500 or 2,000 mg of iron in the form of FeSO4.7H2O with cereal shred as morning ration by 17 or 15 sows failed to cause any increase in blood plasma iron levels, within 360 minutes from uptake. Literature data as well as the results of these analyses have supported the recommendation that Hb variations between 4.96 and 9.93 mmol/l (8-16 g/dl) should be rated as physiological in the blood of pregnant sows. The GDR Standard TGL 35,423 on "Monitoring of Metabolism on Pig Breeding and Fattening Units" should be accordingly amended.