author(s)
Ameer H ALsafah and Jamal K AL-Faragi

abstract
The present study was aimed to evaluate the efficiency of thyme (Thymus vulgaris) on growth performance and antifungal activity on Saprolegnia spp. on Common carp. For this purpose, 100 fingerlings of Cyprinus carpio weight ranged between 75.18-75.36 g were randomly distributed into five treatment groups. Fish were fed with different thyme concentrations: 0.5% (T2), 1% (T3), 1.5% (T4) and 2% (T5). The first group (T1) was serve as control group without any addition of thyme. After 56 days of feeding, blood samples were collected for determination of hematological and biochemical parameters. The fingerlings were challenged with Saprolegnia spp. post feeding trail (at concentration 1×10⁵ zoospore/ml) and their mortalities were recorded up to 15 days. Results of feeding trail in treated groups with thyme supplementation showed significant increase (P<0.05) in growth rate, hematological and biochemical parameters compared with the control group, and the highest values were recorded in T4 supplemented with thyme at concentration of 1.5%. On the basis of our data, the dietary supplementation of T. vulgaris improved the growth rate, hematological, biochemical parameters and survival rate of C. carpio challenged with Saprolegnia spp. This indicates the immunostimulant effect and anti-fungal activity of this feed additive in common carp.