Main research question/goal
Enzyme addition is commonly used in broiler diets to enhance digestibility. This project aims to determine whether a second (putative) effect exists, namely whether these enzymes also have a prebiotic activity. The research questions are: To what extent do endogenous enzymes, which help to break down non-starch-polysaccharides, also drive the gut microbiota? Digestibility and production experiments are performed at ILVO and effects on gut microbiota are done in collaboration with the Veterinary Faculty of Ghent University.
We formulate a number of specific target diets (with a high non-starch-polysaccharide content) to which both single enzymes or a combination of enzymes (xylanase, beta-glucanase) are added. The different diets are fed at varying dosages to the broilers. Commonly-used diets are also always fed to a control group. We try to enhance the disposal of starch from grains (corn or wheat) using several methods, including freezing for several days. The intention here is to separate the enzymatic effect from the prebiotic effect. We quantify the effects on the digestibility while simultaneously studying the effects on the gut morphology, viscosity and microbiota. These experiments test the hypothesis that the enzymes work all in the same way and in some cases a synergistic effect is achieved. Relevance/Valorisation
Positive effects of enzymes added to the diet are very divergent and dependent upon the raw materials in the diet. This variability is expected to increase with an increasing and more diverse use of by-products in broiler diets (e.g. by-products originating from the feed- or bio-fuel industry). Knowledge about the optimal addition of target enzymes is thus becoming increasingly important. From earlier observations we know that the digestibility (availability) of by-products is lower than traditional feed and consequently the gut health of the animal is compromised when using by-products in feed. An optimal prebiotic effect is expected to deliver both better immunity-building, better availability of nutrients, and enhanced gut health of the future broiler.
Iran Ministry of Science, Research and Technology