Document Type : Research Paper
Department of Fisheries Science and Engineering, Faculty of Natural Resources, University of Jiroft, Jiroft, Kerman, Iran
Dezful Fisheries Office, Khuzestan General Fisheries Office, Iran Fisheries Organization, Dezful, Khuzestan, Iran
Department of Plant Production, Faculty of Agriculture, Saravan Integrated Education, Saravan, Sistan and Baluchistan, Iran
The Lavandula angostifolia is a medicinal plant that has the property of strengthening the immune system. In the present study, the effects of different levels of L. angostifolia extract on growth performance, survival rate and blood indices of the grass carp (Ctenopharyngodon idella) (11.01 ± 0.05 g, 15.5 ± 0.3 cm) was investigated. The fish were didtributed in 4 treatments (0 (control), 0.1% (T1), 0.5% (T2) and 1% (T3)). The fish were fed for 8 weeks. The results showed highest and lowest weight in both leaves and lavender groups in T3 and control group, respectively (p < 0.05). The highest and lowest FCR were observed in the control group and T3 treatment, respectively (p < 0.05). WG, BWI and PER values in T3 had the highest value (p < 0.05). CF in treatments containing common lavender was higher than control (p < 0.05). There was no significant difference in HSI (p>0.05). The highest and lowest HSI was observed in control and T2 groups. No mortality was observed in the groups. The hematocrit, hemoglobin, RBC, WBC had significant difference (p < 0.05) but lymphocytes, monocytes, neutrophils, MCH, MCV and MCHC showed no significant difference (p>0.05). The levels of lysozyme, IgM and globulin in experimental treatments were significantly higher than control (p < 0.05). In general, the extract of common lavender has a positive effect on improving the biological status of grass carp.