Are there any natural or synthetic compounds which have a stimulating effect on immunity, especially cellular ones that can be measured (through its effect on interleukin, interferon, T cell proliferation ....etc) in chickens.
All adjuvants used for immunization have immunostimulant effect.
In addition to levamisol the Freunds adjuvant is a potent immunostimulator.
Some plant extracts e.g Tinospora cordifolia, Hippophae rhamnoides, Withania somnifera and indian gooseberry( Phyllanthus emblica are known immunomodulators.