W. Meeus, T. Abeel, J. Adriaen, E. Roelant, S. Aerts, L. Kuterna, E. Vanderbeke, P. Bossier and B. Goddeeris
When using high inclusion levels of plant based ingredients in fish feed, the presence of Anti-Nutritional Factors (ANF) needs to be taken into consideration. Non Starch Polysaccharides (NSP) are recognized as true ANF, causing impaired growth performance and feed utilization. The mode of action of NSP in fish is still not completely understood and is probably multi factorial (Sinha et al., 2011). Increasing digesta viscosity and thereby hindering the action of endogenous digestive enzymes, altering the composition of the gut microbiota, trapping of bile salts which results in elevated excretion and thus affecting cholesterol balance,…are some of the hypothesized mechanisms involved.
NSPase could counteract these negative effects but on the other hand NSPase have the potential of negatively affecting product quality; by liberating the “trapped” energy from NSP itself or through an increased VFA production, the energy level of the diet could be increased. Too high energy levels in the diet can result in undesired fat deposition as visceral fat or in the fillet. Therefor the energy balance and product quality is also studied in this research.
In a previous trial several NSPase formulas (selection based on the used ingredients) were tested. The best performing formula was selected for this experiment.
The goal of this experiment was to determine which concentration results in the best performance in Nile tilapia and to investigate which of the selected parameters are affected.