Effects of the Pomegranate powder on the Body composition, hematological and biochemical indices of the rainbow trout (Oncorhynchus mykiss ).

The aim of this study was to investigate the effects of pomegranate powder on the body composition, hematological, and biochemical indices of rainbow trout (Oncorhynchus mykiss). Pomegranate peel powder was added to the experimental diets at 0 (control), 1, 2, 3 and 4 % with 3 replicates. In a completely randomized design, 450 rainbow trout with an average weight of 45±5 g were reared in 15 cement ponds for 60 days. Adding pomegranate peel powder to the fish diet had a significant effect on the carcass quality, hematological, and biochemical parameters (P<0.05). The results also showed that the ash content of the fish fed with pomegranate peel powder did not significantly differ different (P<0.05), while other parameters such as moisture, protein, and fat contents were significantly different (P<0.05). Moreover, the highest number of red blood cells was observed in the control group, but there was no significant difference among other treatments (P<0.05). In terms of white blood cell count, the highest number was observed in the treatment of 4% pomegranate peel powder and the lowest value was in the control group. Also, the addition of pomegranate peel powder had a significant effect on the biochemical parameters (glucose, cholesterol, triglyceride, protein, and albumin) (p <0.05). The results of this study showed that the addition of pomegranate peel powder at 4% in the diet would have a significant effect on the blood parameters related to the immune system in rainbow trout.