Objective: This study was conducted to evaluate the effects of different levels of Pahak (green Khalal-stage date) on growth performance, blood biochemistry, carcass characteristics, intestinal morphology, and gastrointestinal microbial population in Japanese quail.

Methods: A total of 360 chicks were used in a completely randomized design with four dietary treatments and six replicates per treatment (15 birds per replicate) for a 35-day experimental period. The treatments consisted of: (1) control (basal diet without Pahak); (2) 5% dietary Pahak; (3) 10% dietary Pahak; and (4) 15% dietary Pahak.

Results: Body weight was not influenced by the dietary inclusion of Pahak at any stage of the experiment. Inclusion of 5% Pahak reduced feed intake and improved feed conversion ratio as well as energy and protein efficiency ratios, whereas 15% Pahak increased feed intake (P < 0.05). Dietary inclusion of 10% and 15% Pahak decreased total cholesterol levels, and all three Pahak levels reduced the cardiac risk ratio and atherogenic index (P < 0.05). Diets containing 10% and 15% Pahak respectively decreased and increased relative carcass and liver weights (P < 0.05). The lowest liver weights were recorded in birds receiving control diet and 5% Pahak, whereas the highest liver weight occurred with the 15% inclusion level (P < 0.05). Compared with the control group, feeding 5% Pahak increased villus height and decreased submucosal thickness in the duodenum (P < 0.05). The greatest submucosal thickness was observed in birds fed 15% Pahak (P < 0.05). Compared with the control group, inclusion of 10% and 15% Pahak reduced villus height, villus thickness, and the villus height-to-crypt depth ratio in the ileum (P < 0.05). Moreover, the 15% Pahak level increased both submucosal and muscular layer thicknesses (P < 0.05). Feeding 5% and 10% Pahak led to a moderate reduction in the average number of goblet cells in the ileum, whereas 15% Pahak markedly reduced goblet cell counts (P < 0.05). Among treatments, the largest and smallest ileal villus surface areas were observed in birds fed 5% and 15% Pahak, respectively (P < 0.05). Although crypt depth was not significantly affected by Pahak, its values increased quadratically with increasing Pahak level (P < 0.05). Compared with the control, inclusion of 10% and 15% Pahak increased Salmonella-Shigella, Clostridia, and coliform colonization in the ileum (P < 0.05). Compared to the control, the inclusion of 5% Pahak reduced the total aerobic bacterial colonization in the cecum, while the 15% level increased the colonization of these bacteria (P < 0.05). Moreover, the colonization of Salmonella-Shigella and coliforms in the cecum of birds fed the 15% Pahak diet increased compared to the other treatments (P < 0.05).

Conclusion: It is concluded from the results that Pahak can be safely utilized at a dietary inclusion rate of 5% for Japanese quail during the first 35 days of the rearing period, with no deleterious effects on productive performance.