Method of treating immature birds with IL-2

摘要

A method of causing an animal to gain weight by administering that animal a T-cell growth factor comprising Interleukin-2 (IL-2) in an amount effective to cause that animal to increase in weight is disclosed. A method of treating birds by administering birds in ovo avian IL-2 is also disclosed. The method is preferably carried out on chicken with 30K chicken IL-2 on about the eighteenth day of incubation. The method may be employed to increase the weight of treated birds after hatch. A vaccine may optionally be administered concurrently with the avian IL-2.