Hematology of the neonatal calf. III. Frequency of congenital iron deficiency anemia.

The hematocrits of 258 Holstein-Friesian and Jersey calves were determined during the first 3 days following birth. Hematocrit values of 25% or less were observed in 15.8% of the calves and hematocrits of 20% or less were observed in 6.9% of calves from apparently normal dams. The serum iron concentration of neonatal calves with hematocrits of 25% or less was significantly lower than the value recorded in calves with hematocrits above 25% and there was a direct correlation between PCV and serum iron concentration. The data presented suggested that prenatal development of iron deficiency is an important cause of anemia in neonatal dairy calves. Factors which may be important in pathogenesis are discussed.