Effects of green tea (Camellia sinensis) Oil on Feed Utilization and Hametological Parameters of Rainbow Trout (Oncorhynchus mykiss)

In the study, experiments were conducted to determine effects of green tea oil (Camellia sinensis) on the growth rate, feed utilization and hematological parameters of rainbow trout (Oncorhynchus mykiss). Fish (76.25±2.75 g) were fed diets supplemented with different concentrations of green tea oil (%0.25, %0.5, %1.0). Weight gain (WG), feed conversion ratio (BDI) and some blood parameters were determined in the rainbow trout. It was determined that the values of WBC, GRAN, HGB, HCT, MCH, MCHC, PLT, PDW and PCT were increased with respect to control group at the end of 42 days feeding with green tea oil. However, groups treated with green tea oil stimulated megakaryocytes (increased PLC-R levels), which also increased platelet production. Feed evaluation ratio varied between 1.83-4.53. At the end of the experiment, it was determined that the feed evaluation ratio decreased with the increase of the amount of green tea oil in the groups. It is thought that the bioactive substances in the lipophilic property of green tea oil provide thermogenic stimulation in fishes by synergistic effect, which causes weight loss. Besides, it was determined that antioxidants such as hematopoiesis and catechins in hematopoietic organs of green tea oil act on the granulocyte cell group.