Marine Secondary Metabolites (MSM) from Macro Algae Enhance Bacterial Clearance in Hemolymph of Penaeus monodon

Abstract

Marine secondary metabolites (MSM) from macro algae were incorporated into four experimental feeds for juvenile shrimp (Penaeus monodon) as follows: 1.0% Hypnea musciformis extract (diet 1); 0.1% H. musciformis ex- tract (diet 2); 1.0% H. musciformis extract with 500 mg Ulva fasciata extract and 50 mg of the antibiotic levamisole (diet 3); 1.0% H. musciformis with 500 mg U. fasciata per kg body weight (diet 4). Diet 3 enhanced bacterial clearance to 99.69% in the hemolymph of shrimp challenged with Vibrio alginolyticus and Vibrio fischeri, significantly higher than clearance rates in all other treatments and the unmedicated control. Results suggest that feed containing MSM is a good alternative to application of antibiotics in control- ling bacterial diseases in shrimp.