Effect of garlic (Allium sativum L.) extract on some heamatological parameters and immune response of rainbow trout fingerlings

Background & Aim: Continuous use of antibiotics leads to drug resistance and thereby to a reduced efficacy of the drugs. Antibiotics accumulate in the environment and fish pose a potential risk to consumers and to the environment.Increased public awareness of the negative effects caused by overexposure to synthetic chemicals has led to the search for ‘‘green drugs’’, such as organic and synthetic chemical-free food products. The main goal this work was effect of Allium sativum on some parameters and immune response of rainbow trout fingerlings. Experimental: A 500 fish with weight 10.47±0.29 g were purchased from a fish farm of Yasoj, Southern Iran. In this study, 15 fiberglass tanks (300 L) were used. Experimental treatments were different levels of  A. satinum extract included 0.05, 0.1, 0.15, and 0.2 g/kg  that were added to the diet. Control group was no add supplement to the diet. In final, biochemicals and hematologals were analyzed.  Results & Discussion: Results indicated that 0.05 g/kg garlic extract no had on some paramteres, including RBC, hematocrite percent, hemoglobin and white blood cell, while other experimental groups  had significant effects on the paramters serum. The most of albomin and globulin were obtined from 0.05 g/kg garlic extract trteatment. The highest of lysozyme activity was observed in 0.1 g/kg garlic extract and the lowest  lysozyme activity was obtined from control group. Recommended applications/industries: The obtained results indicated that A. sativum extract had immunostimulatory effect on these immunological variables of fingelings of rainbow trout and the best levels of extract effect 0.15 g/kg is recommended.