Breeding Forms of Heifers and Serum ^|^alpha;1-Acid Glycoprotein and Sialic Acid

Serum α1-acid glycoprotein (α1AG) and sialic acid (SIAL) of heifers were examinedin relation to changes in breeding forms in a pubulic pasture land. The α1AG and SIAL levels were significantly higher after pasturing than before, returning to the previous levels at 2 months of pasturing. The heifers reared within the public drylot during winter showed similar changes in α1AG, while the level was lower, and no changes were observed in SIAL levels. The results suggested that heifers might be in immunosuppressive state during some weeks after moving to different breeding forms, such as pasturing.