CHRONOBIOLOGICAL INFLUENCE OF VITAMIN-C ON CHICKEN IMMUNE FUNCTIONS

One-hundred and twenty broilers, Ross strain, (60 males and 60 females ) were used to evaluate the effect of dietary vitamin C treatment dura tion and the period in which it is carried out on the humoral and cell ular immune response. Using a higher dietary dose of vitamin C (500 pp m) in broilers free from stress and an inactivated and emulsified vacc ine containing Newcastle disease virus (NDV) and a strain of Pasteurel la anatipestifer (serotype 1), the authors show that the production of circulating antibodies to bacterial and viral antigens and lymphocyte evaluation are conditioned by the time in which vitamin C is suppleme nted. In fact supplementing vitamin C in the first weeks of life the a ntibody production, the percentage of DNA synthesizing cells and the p ercentage of cells able to effect instantaneous basis incorporation in to the molecular DNA chain (S-phase cells) increase respect to continu ous vitamin supplementation and to basal diet.