“…Erythrocytes from various animal species that differ in oligosaccharide composition were used. Agglutination of erythrocytes from cows, horses, and pigs requires NeuAc␣2,3Gal or NeuGc␣2,3Gal recognition, while agglutination of those from chickens, ducks, guinea pigs, and humans (type O) requires NeuAc␣2,3Gal and NeuAc␣2,6Gal recognition (7,10,12). To explore the receptor specificity of H9N2 viruses, hemagglutination assays were conducted with 50 l 0.5% host red blood cells from each of the following: chicken, duck, goose, pigeon, quail, buffalo, donkey, goat, pig, dog, guinea pig, and human (type O) in phosphate buffer solution (pH 7.4) at 4°C for 45 min, as described previously (12).…”