Abstract: | Infective hookworm larvae of Ancylostoma caninum showed chemotaxis on agar plates in a dog serum gradient. This chemotactic behaviour remain unaltered using an ultrafiltrated serum fraction with a molecular weight less than 500. Gelfiltration of this ultrafiltrated fraction revealed a factor with a molecular weight of 480 causing chemotaxis. The chemotactic activity of the factor was destroyed after a pronase treatment. We conclude that the factor could be a polypeptide. |