Abstract

The effect of 0, 70, 80, and 100% levels of extruded feed on biochemical and hematological indices of rainbow trout (Oncorhynchus mykiss) was studied at 480 fries with an average weight of 90±5 g in the form of a completely randomized design. 16 fish were randomly collected from each treatment at the middle and end of the 90-s experiment. According to the findings, the highest amount of protein in the carcasses was related to fish fed with 85% extruded feed. Also, the protein content of carcass was significantly different from that of extruded food before consumption (p <0.05). The highest amount of carcass Ca and Mn was related to 85% extruded food. There was also a significant difference between Mn and Ca levels in carcasses before and after extruded feed (p <0.05). There was no significant difference in albumin levels during the treatments. In the mid-period measurement, a significant difference was observed between total blood protein of 100% pellet and 70% extruded treatment (p <0.05). The highest was observed in 5.2 g/dl of fed with 70% extruded feed and the lowest was 4.24g/dl in the group of fed with 70% pellet. In general, the results showed that the use of high levels of extruded could be replaced with pellet supplements in the diet of rainbow trout (Oncorhynchus mykiss) without any negative effect on blood indices.

Keywords: Albumin, Rainbow trout, Total protein, Extruded