Effect Of dill (Anethum graveolens) and garden cress (Lepidium sativum) dietary supplementation on growth performance, digestive enzyme activities and immune responses of juvenile common carp (Cyprinus carpio)

In this study, Bilen et all, studied that the effect of dietary supplementation of dill (Anethum graveolens) and garden cress (Lepidium sativum) on the growth performance, digestive enzyme activities and immune responses of juvenile common carp (Cyprinus carpio) in addition to their disease resistance to Aeromonas hydrophila and Edwardsiella tarda. Common carp were fed for 45 days with two different doses of extracts of plant (1 and 2 g kg−1) in four treatment groups: dill 1 g kg−1 (D1) and 2 g kg−1 (D2) and garden cress 1 g kg−1 (G1) and 2 g kg−1 (G2). At the end of the study, the fish were challenged with A. hydrophila and E. tarda. Results showed that the final fish weight and specific growth rates were higher in the G2 group than in the control group (C) and other experimental groups (D1, D2 and G1) (P < 0.05). Compared with the control group, there were no differences in the feed conversion ratio (FCR) in the experimental groups, except the D1 group, (P > 0.05). In the D1 group, FCR was significantly increased. Trypsin activity was significantly decreased in the G2 group. Compared with the control group, amylase activity was the highest in the D2 group (P < 0.05). There were no differences in lipase activities among the groups. Lysozyme activity was significantly increased on the 15th day of the study in D1 and G2 groups compared with that in the control group (P < 0.05). On the 30th day, lysozyme activity was increased in the D2 group compared with that in the control group (P < 0.05). No differences were observed in lysozyme activity among the groups on the 45th day. Myeloperoxidase (MPO) activity was elevated in the G2 group on the 15th day (P < 0.05). The highest MPO activity was observed in the D1 group (P < 0.05) on the 30th day of the study. On the 45th day, the MPO activity in all experimental group's (P < 0.05) was higher than that in the control group. At any sampling time of the study, superoxide anion production was elevated in all experimental groups compared with that in the control group. Moreover, when challenged with A. hydrophila, survival rates of common carp in G1, G2 and D1 groups were significantly increased, and when challenged with E. tarda, those of common carp in G2 and D1 groups were also elevated. The results of the study showed that cress had immunostimulatory effects in common carp and increased the fishes' growth rate.