Effects of Combined Application of NRTUAs and ABP on Growth and Humoral Immunity of Chicks

[Objectives] The paper was to study the effects of combined application of nonreplicating Toxoplasma uracil auxotrophs (NRTUAs) and Agaricus blazei Murill polysaccharide (APB) on growth and humoral immunity of chicks. [Methods] A total of 120 one-day-old female Hyline brown laying hens were randomly divided into 4 groups, 30 hens for each group. The chicks in group 1 were subcutaneously injected with NRTUAs and fed on the diet containing APB; the chicks in group 2 were subcutaneously injected with NRTUAs; the chicks in group 3 were subcutaneously injected with equal volume of PBS, and fed on the diet containing APB; the chicks in group 4 were subcutaneously injected with equal volume of PBS. The body weight of chicks in each group was counted at the 21st, 42nd, 84th and 112th week. During this period, blood samples were collected from chicks in each group at 0, 7, 14, 21, 28 and 35 d post immunization against Newcastle disease (ND), and serum was separated to detect the antibody titer of ND. [Results] The combined application of NRTUAs and APB had no effect on growth of chicks, but promoted the humoral immune response of chicks, significantly improved the ND antibody level of chicks, and could maintain high levels of antibodies in the body for a long time. [Conclusions] The study lays a theoretical foundation for further developing the clinical application of NRTUAs and APB.