Effects of Cinnamon supplemented diet on growth performance, hematological parameters, blood biochemical and immunological indices of rainbow trout (Oncorhynchus mykiss) fingerlings

Dietary cinnamon supplementation has several bioactive compounds with growth-promoting and immunomodulation potential, which is suggested for finfish species. This study evaluated the inclusion of cinnamon at 0, 1, 3, 6, and 12 g/kg diet in Oncorhynchus mykiss fingerlings. After eight weeks, the best growth performance, and feed utilization parameters were calculated in fish treated with 12 g/kg (P < 0.05). Further, the white blood cells and lymphocyte levels were significantly increased and Neutrophil was significantly decreased in fish fed cinnamon at 12 g/kg compared to those fed 0-6 g/kg (P < 0.05). After the feeding trial, in the studied immune and biochemical indices, immunoglobulin ROS, Lysozyme was significantly increased (P<0.05), and Glucose decreased significantly (P < 0.05) in fish treated with cinnamon at 12 g/kg compared to fish fed 0-6 g/kg. Moreover, treated fish with cinnamon had higher levels of C3, C4, total protein and Albumin than the control with the highest value in fish treated with 12 g/kg. The results showed the positive influence of the inclusion of cinnamon in the diets for rainbow trout fingerlings on the growth performance, feed utilization, blood analysis, and immune functions. According to the results, it can be concluded that 12 g cinnamon powder per kg diet is suggested with no adverse effects to improve growth performance, feed utilization and health status in rainbow trout fingerlings.