The essential oils of some medicinal plants on the immune system and growth of rainbow trout (Oncorhynchus mykiss)

Abstract

Background & Aim: In present study, some of the Iranian endemic medicinal plants were used to evaluate potential as well as therapeutic agent and immunostimulants in aquaculture. The essential oils of five species from leaves and inflorescence were used to determinate the effects on immune system in rainbow trout (<em>Oncorhynchus</em> <em>mykiss</em>). Experimental: The experimental in a completely randomized design with 7 treatments and 3 replicates and each replicate fish was divided into 12 pieces. An experiment with 252 fishes with average weight 50±5 g for 8 weeks was conducted. The experimental treatments were: essential oil of 1. <em>Satureja bachtiarica</em> Bunge; 2. <em>Thymus daenensis</em> Celak; 3. <em>Satureja Khuzestanica</em> Jamzad; 4. <em>Dracocephalum multicaule</em> Benth; 5. <em>Mentha longifolia</em> L) 1% oil); 6. Normal diet + olive oil; 7. Normal diet (control). Results & Discussion: The results of analysis of variance showed significant different (<em>p</em>≤0.05) between almost of factors of immune system and growth of rainbow trout. The results showed the highest levels of immune factors relating to the percentage of phagocytosis and the number and rate of crime phagosite Igm three essential oils of <em>M. longifolia</em>, <em>S. khuzestanica</em>, and <em>D. multicaule</em>. Lymphocytes in the blood and blood heterophile between yourself and the control diet containing the essential oil of <em>Satureja bachtiarica</em> significant difference (<em>p</em>≤0.05) was observed. There was no significant difference between some of the factors of immune system and growth of rainbow trout (hematocrit, hemoglobin, monocytes and etc). Industrial and practical recommendations: The use of essential oils and herbs, especially the <em>Mentha longifolia</em> and <em>Satureja bachtiarica </em>can improve the status indicator.