Influence of dietary vitamin C and bovine lactoferrin on blood chemistry and non-specific immune responses of Japanese eel, Anguilla japonica

• Published in: Aquaculture 2007-07, Vol.267 (1), p.31-37
• Main Authors: Ren, Tongjun, Koshio, Shunsuke, Ishikawa, Manabu, Yokoyama, Saichiro, Micheal, Faddy Raffat, Uyan, Orhan, Tung, Ha Thanh
• Format: Article
• Language: English
• Subjects: Anguilla japonica; Animal and plant ecology; Animal aquaculture; Animal productions; Animal, plant and microbial ecology; Aquaculture; Aquatic life; Ascorbic acid; Bactericidal activity; Biological and medical sciences; Blood; blood chemistry; eel; feed composition; feeds; fish culture; fish feeding; Fundamental and applied biological sciences. Psychology; General aspects; immune response; Immune system; Japanese eel; Lactoferrin; Lysozyme activity; Sea water ecosystems; Synecology; Vitamin C
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2007.03.033

A trial was conducted to determine the effect of ascorbyl-2-monophosphate Na/Ca (AMP-Na/Ca) and bovine lactoferrin (Lf) on blood chemistry and non-specific immune response of Japanese eel juveniles. Test diets with 32 or 762 mg AsA/kg diet, and with or without 500 mg Lf/kg diet were fed to juvenile Japanese eels (75.5 ± 4.4 g) once a day for 3 weeks. A diet without AMP-Na/Ca and Lf supplements was employed simultaneously as a negative control. Liver AsA content of fish fed diets containing 762 mg AsA/kg was significantly ( P < 0.05) higher than fish fed diets containing 32 mg AsA/kg regardless of Lf level. Fish fed diets containing 762 mg AsA/kg showed lower serum glutamic oxaloacetic transaminase (GOT), lactate dehydrogenase (LDH), and serum total bilirubin (T-Bil) than fish fed diets containing 32 mg AsA/kg and the negative control group ( P < 0.05), respectively. Lf was not a significant factor on those parameters. Fish fed diets containing 762 mg AsA/kg showed significantly higher lysozyme activity (LA) of mucus and serum, and bactericidal activity of mucus than the fish fed the diet containing 32 mg AsA/kg. Lf was a significant factor on serum LA, and there was an interaction between AsA and Lf on serum bactericidal activity. These results demonstrated that AMP-Na/Ca is an effective AsA source and higher level in the diet improved blood chemistry and non-specific immune function of Japanese eel. Moreover, the highest serum LA and mucus bactericidal activity were found in eel fed the diet containing the highest AsA content with supplemental Lf.