Using T cell lymphokines of hyperimmunized chickens with Salmonella pullorum to enhance immune response of layer hens against avian influenza

The current study used immune lymphokines from chickens that had been hyperimmunized with Salmonella pullorum to improve the resistance of layer hens at the production stage to AIV-type (H5N1) infected hens (SP). Two groups (each consisting of 25 pullets) were treated; the first group received three doses of SP vaccination at 12, 14, and 16 weeks; the second group received no vaccination and was used as a control group. At 18 weeks, the T cells of the first group released immune lymphokines (S-ILK), whereas the T cells of the second group produced non-immune lymphokines (N-ILK). The following procedures were then used on a total of 100-layer hens (ISSA brown), divided into four groups of 25 each. G1: S-ILK treatment and H5N1 challenge. G2: N-ILK treatment and H5N1 challenge. G3: Untreated and challenged to (H5N1). G4: untreated or unchallenged. Blood samples were obtained at 31, 32, and 33 weeks of age to assess the (IgG, IFN-γ). Additionally, lung and tracheal tissues were obtained to assess the viral load of influenza RNA copies at (7 and 14) days following the challenge. The experiment's findings indicated that the first group produced the highest mean (IgG and IFN-γ) titers and had the lowest mortality of the other groups. The findings of the viral load test showed that G2 and G3 had the highest number of influenza RNA copies and had significantly lower egg production than G1, which had the lowest viral load and kept egg production at a normal level. The conclusion of the current study shows that using SILK gives layer hens a higher level of homogeneous protection against AIV without any dangers during production