The objective of this study was to investigate the effect of Spirulina Platensis algae (SP) or Turmeric Powder (TP) on some antioxidants, interferon proteins, immune response and its relationship to productive performances. A total number of 150 Golden Montazah (GM) laying hens and 15 cocks were kept individually in layer's cages and distributed randomly (divided equally into 5 treatment groups) during laying period from 29 to 40 weeks of age. The 1st group (T1) was fed the basal diet and served as a control group (without supplementation). The 2nd and 3rd groups were fed the basal diet supplemented with 2 or 3 g SP/kg diet, respectively. However, the 4th and 5th groups were fed the basal diet supplemented with 4 or 6 g TP/kg diet, respectively.
The obtained results indicated that supplementing layer diet with 2, 3g Sp/kg and 6 g TP/kg significantly improved feed conversion ratio (FC) compared to the control group during the whole period (29 to 40 weeks old). Hens received diet supplemented with 3 g SP/kg or 6 TP/kg had significantly higher egg number (EN), egg weight (EW) and egg mass (EM) during the whole period than those of the control group. Feeding GM layers on diets supplemented with 3 g SP/kg or 6 g TP/kg significantly increased shell weight percentage compared to the control group. Supplementing layers diets with either SP or TP at each tested levels significantly decreased blood cholesterol, total lipids and low density lipoprotein (LDL). While 3 g SP/kg or 6 g TP/kg groups recorded significantly higher values of high density lipoprotein (HDL), total antioxidant capacity (TAOC) and glutathione peroxidase (GPX), and some immunological parameters and such as antibody titers against Newcastle Disease Virus (NDV), Avian Influenza (AI), antibody against sheep red blood cells (SRBC) and Interferon proteins (IFN-γ) concentration) compared to the control group. The averages of fertility and hatchability percentage of total eggs were significantly increased for the hens received diet supplemented with 3 g SP/kg compared to all other groups. Conclusively, it could be recommended to supply layer diets with SP or TP for better productive and reproductive performance as well as improved immune responses during the laying period.