Effect of iron treatment on erythrocyte parameters in postnatal anemia of the pig.

The development of postnatal anemia and the preventive and curative effect of iron supplementation were examined in 34 piglets from three litters of Norwegian Landrace pigs. A prostaglandin analog was given on day 111 or 112 of pregnancy, and the piglets were removed by caesarean section. Seventeen piglets were given 180 mg iron as colloidal ferridextran subcutaneously at birth (0 = day group); the remaining 17 were given the same amount on day 13 (13-day group). The piglets had access to a milk substitute from day 1 to day 7 and pelleted food for piglets after day 13. From about 4 weeks of age the piglets ate considerable amounts of pellets. The red blood cell count (RBC) and hemoglobin concentration (Hb) at birth were 3.2 +/- 0.4 (SD) x 10(12)/L and 80.4 +/- 8.1 x 10(12) g/L, respectively. In both groups Hb, RBC, mean corpuscular volume (MCV), and particularly packed cell volume (PCV) decreased markedly the first day after birth. In the 13-day group there was a further decrease until treatment with iron on day 13. Injection with iron on day 13 led to a rapid increase in the above mentioned parameters, with statistically significant increases for Hb, PCV, and MCV four days after treatment. The calculated mass of hemoglobin was fairly constant until treatment in the 13-day group. In the group given iron at birth the data obtained indicate that the amount of iron given is insufficient to sustain a production of normal-sized erythrocytes with a normal mean corpuscular hemoglobin concentration for more than approximately 21 days. Furthermore, the present study also indicates that MCV is a sensitive indicator of iron availability in piglets.