Influence of combined vitamins C and E on non‐specific immunity and disease resistance of rainbow trout, Oncorhynchus mykiss (Walbaum)

Abstract

The effect of various combinations of vitamins C and E on immune response and disease resistance was investigated in rainbow trout, Oncorhynchus mykiss (Walbaum). The following combinations of vitamins were included in the diet (C/E): 0/0, 0/800, 2000/0, 30/30, 30/800, 2000/30, 2000/800. Liver ascorbic acid and alpha-tocopherol contents reflected the dietary treatments well. Complement levels showed no significant differences. The combination of the high dietary doses of vitamins C and E significantly stimulated lymphoproliferation induced by Concanavalin A when compared with fish fed a low level of both vitamins, but also when compared with fish fed a low level of vitamin C and a high level of vitamin E. The highest macrophage oxidative burst activity, measured by chemiluminescence, was found in fish receiving both vitamins at high levels. In the disease resistance experiments, the best survival rates in trout infected with viral haemorrhagic septicaemia virus were achieved with diets containing both vitamins at a high level, or at least one at a high and the other at a low level. Highest mortalities in fish infected with Yersinia ruckeri occurred in trout fed double-deficient or double low diets. The best survival of fish exposed to Ichthyophthirius multifiliis was achieved with diets high in one and low in the other, or high in both vitamins. However, differences were not statistically significant in the parasite experiment.

Influence of Stress and Dietary Natural‐Source Vitamin E on Nonspecific Immunocompetence, Tissue Tocopherol Composition, and Postslaughter Fillet Oxidative Stability in Sunshine Bass

“…Elevated levels of vitamin E were accompanied by an increase in phagocytic activity in rainbow trout (Clerton et al 2001) and gilthead seabream Sparus aurata (Mulero et al 1998;Ortuño et al 2000). Enhanced lysozyme activity has been reported for malabar grouper Epinephelus malabaricus (Lin and Shiau 2005), rainbow trout (Kiron et al 2004), and Indian major carp Labeo rohita (Sahoo and Mukherjee 2002) fed increasing levels of vitamin E. Increased oxidative burst has been reported in association with vitamin E supplementation, but these studies typically observed enhanced responses in conjunction with increased levels of other micro-or macronutrients, such as vitamin C (Mulero et al 1998;Wahli et al 1998;Sealey and Gatlin 2002b) or lipid (Lin and Shiau 2005). Statistically significant effects were not reported in all studies, and the variability of the data was often cited as a limitation.…”

Effects of Vitamin C and E Administration on Leukocyte Counts in Rainbow Trout (Oncorhynchus mykiss)

“…The dietary supplements of vitamins have promised reducing the severity of disease, and enhancing of immune response [35,36]. Leukocytes are defense mechanism indicators in fishes, and it has shown that vitamins E and C are potent antioxidants that can provide the protection to the leukocyte function [5,18,25,26]. The vitamin E and/or C supplementation in the diet of fishes has shown a greater efficiency in the production of antibodies, lysozyme levels, phagocyte activity and stress attenuation [6,14].…”

“…In fishes, essential nutrients, including fatty acids, proteins, polysaccharides, vitamins, and some minerals have pivotal importance to reinforce their immune functions [4]. Vitamins C and E are among the most important nutrients influencing specific and non-specific immune responses of fishes [5][6][7][8]. Vitamin C is an essential micronutrient and water-soluble antioxidant in biological fluids, which is associated to biochemical reactions in cells and tissues.…”

“…Furthermore, they are important antioxidants offering protection against oxidative damages [20], enhancing the resistance of red blood cell membranes [18,[21][22][23][24], protecting leukocyte functions [5,18,20,25,26], and influencing blood cell indices such as leukocytes profile [24,27].…”

Aquaculture Health Management: A new Approach

“…Elevated doses of vitamin C have been shown to enhance immune responses such as macrophage activities, cell proliferation, natural killer cell activity, and complement and lysozyme levels in fish [101]. A positive effect of vitamin C together with vitamin E on the immune response of fish has also been found [102,103]. Feeding high levels of ascorbic acid has been reported to enhance protection against bacterial infections viz.…”