The Effects of Balanced Diets with Soy Bean Extract or Meat and Bone meal on Muscle and Liver Tissue Protein and Glycogen Levels of the Nile Tilapia (Oreochromis niloticus L.) Infected with Vibrio anguillarum

This study investigated the effects of balanced diets with solvent extracted soy bean and meat and bone meal on the levels of protein and glycogen in muscle and liver tissues of the Nile tilapia (Oreochromis niloticus L.) infected with Vibrio anguillarum. Compared to the control diet (fishmeal only), diets with solvent extracted soy bean (SBM) and meat and bone meal (MBM) significantly lowered (P<0.05) the protein levels in liver tissues. However, glycogen levels in muscle and liver tissues were also lower in fish fed with SBM and MBM diets than fish fed with control diet. When fish infected or not infected with V. anguillarum compared within the same diet groups, the liver protein levels were measured significantly higher (P<0.05) on day1, day3 and day5 of following injection. Glycogen levels both in muscle and liver tissues were also found to be significantly higher (P<0.05) in infected fish compared to control fish during the experiment. Considering the level of increase of metabolic reserves in muscle and liver tissues, it might be concluded from this experiment that the Nile tilapia has utilized SBM diet better than MBM diet under stress. Further research concentrating on higher amounts of solvent extracted soy bean and meat and bone meal, different environmental conditions and doses of infection with V. anguillarum and immune response parameters including physiological and cellular stress responses is needed in order to identify the effects of dietary plant and animal protein sources on overall mobilization of metabolic reserves in the Nile tilapia infected with V. anguillarum.