title: Dietary Supplementation of Magnesium Oxide (MgO) Nanoparticles for Better Survival and Growth of the Freshwater Prawn Macrobrachium rosenbergii Post-larvae.
abstract: This study was performed to assess the growth-promoting potential of dietary magnesium oxide nanoparticles (MgO NPs) in Macrobrachium rosenbergii post-larvae (PL). MgO NPs were supplemented at 0, 100, 200, 300, 400 and 500 mg kg-1with the basal diet (containing 0.95 g Mg kg-1); the concentrations of Mg in MgO NP-supplemented diets were increased correspondingly (1.07, 1.15, 1.24, 1.37 and 1.46 g Mg kg-1respectively). MgO NP-supplemented diets were fed to M. rosenbergii PL (initial weight 0.11 ± 0.04 g) for a period of 90 days. In the carcasses of experimental prawns, the content of Mg was found to be elevated significantly with respect to the individual diet (102.14, 183.29, 205.46, 221.03, 237.10 and 254.36 μg Mg g-1respectively) when compared with that of the control. The contents of Cu, Zn, Fe, Ca, Na and K levels were also found to be elevated in the carcasses of experimental prawns. Significant (P < 0.05) improvements were observed in nutritional indices [survival rate (SR), weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR) and protein efficiency ratio (PER)], activities of digestive enzymes (protease, amylase and lipase), concentrations of basic biochemical constituents (total protein, amino acid, carbohydrate, lipid, profiles of amino acids and fatty acids) and population of haemocytes [total and differential (hyalinocytes, semigranulocytes and granulocytes)] in all the test PL. Maximum performance was recorded in 500 mg kg-1MgO NP-supplemented-feed-fed PL. There were no significant elevations recorded in activities of antioxidant enzymes [superoxide dismutase (SOD) and catalase (CAT)], lipid peroxidation (LPO) and metabolic enzymes [glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT)] recorded in any of the MgO NP-supplemented-feed-fed PL when compared with the control. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed increases in the staining intensity of polypeptide bands resolved in 500 mg kg-1MgO NP-supplemented-feed-fed PL when compared with the control. Based on the gradual improvement in attaining survival, growth, FCR, biochemical constituents and haemocyte population, this study recommends MgO NP supplementation of 500 mg kg-1for sustainable maintenance of M. rosenbergii PL. As the studied highest concentration of MgO NPs showed the best performance, it is necessary to study with beyond 500 mg kg-1of MgO NPs to optimize the actual concentration.
authors.affiliation: Department of Zoology, Bharathiar University, Coimbatore, Tamil Nadu, 641046, India.
authors.forename: Veeran
authors.initials: V
authors.lastname: Srinivasan
authors.affiliation: Department of Zoology, Bharathiar University, Coimbatore, Tamil Nadu, 641046, India. bhavan@buc.edu.in.
authors.forename: Periyakali Saravana
authors.initials: PS
authors.lastname: Bhavan
authors.affiliation: Department of Zoology, Bharathiar University, Coimbatore, Tamil Nadu, 641046, India.
authors.forename: Gopalan
authors.initials: G
authors.lastname: Rajkumar
authors.affiliation: Department of Zoology, Bharathiar University, Coimbatore, Tamil Nadu, 641046, India.
authors.forename: Thangavelu
authors.initials: T
authors.lastname: Satgurunathan
authors.affiliation: Department of Marine Science, Bharathidasan University, Tiruchirappalli, Tamil Nadu, 620024, India.
authors.forename: Thirunavukkarasu
authors.initials: T
authors.lastname: Muralisankar
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D019587:Dietary Supplements; D005618:Fresh Water; D007814:Larva / Q000187:drug effects* / Q000254:growth & development* / Q000378:metabolism; D008277:Magnesium Oxide / Q000008:administration & dosage* / Q000494:pharmacology*; D053758:Nanoparticles / Q000008:administration & dosage*; D033541:Palaemonidae / Q000187:drug effects* / Q000254:growth & development*
chemical_list: D008277:Magnesium Oxide
keywords: Catalase; FCR; GOT; GPT; Growth; Haemocyte population; Lipid peroxidation; Macrobrachium rosenbergii; MgO NPs; SOD; Total protein