Effects of anthraquinones extracted from Rheum officinale Bail on the growth, non-specific immune response of Macrobrachium rosenbergii

The effects of anthraquinone extracted from Rheum officinale Bail on growth, some non-specific immunite parameters, and disease resistance of Macrobrachium rosenbergii were studied in this experiment. M. rosenbergii were randomly divided into five groups: a control group was fed with basal diet, and four treated groups fed with basal diet supplemented with 0.05%, 0.1%, 0.2%, and 0.4% anthraquinone extract for 8 weeks, respectively. The growth, the variations of haemolymph lysozyme, alkaline phosphatase, nitrogen monoxide, total anti-oxidative capacity, glutathione peroxidase, and malondialdehyde content and the relative level of hepatic HSP70 mRNA were investigated. The growth gain rate, length gain rate, haemolymph alkaline phosphatase activity and the relative level of hepatic HSP70 mRNA of M. rosenbergii fed with 0.1% anthraquinone extract for 6 or 8 weeks were higher than those of the control. Weight gain rate and haemolymph alkaline phosphatase activity of M. rosenbergii fed with 0.2% anthraquinone extract for 8 weeks were higher than those of the control. However feed conversion ratios of M. rosenbergii fed with 0.1% and 0.2% anthraquinone extracts for 8 weeks were lower compared to those of the control (P<0.05). The haemolymph lysozyme activity and total anti-oxidative capacity in the group fed with 0.05% anthraquinone extract for 8 weeks were significantly higher than those of the control. However, there were no significant differences in haemolymph nitrogen monoxide concentrations and glutathione peroxidase activities between all treatment groups and the control. The present study suggested that the ingestion of 0.1%-0.2% anthraquinone extracts supplemented with a basal diet had the potential to stimulate immunity, increase the gene expression of HSP70, and promote the growth of prawns. (C) 2010 Elsevier B.V. All rights reserved.