Fibres Making Up Wheat Cell Walls in the Context of Broiler Diets

In this paper, the non-starch polysaccharides (NSP) that make up most of wheat fibre in broiler diets are discussed. Wheat is the prevalent dietary energy source in European wheat-based broiler diets, although it contains large amounts of such NSP. They are mostly present in the wheat cell walls and are composed of arabinoxylan (AX), mixed linked β-glucan and cellulose. Due to their physicochemical properties, they evoke anti-nutritional effects in the gastrointestinal tract (GIT) of poultry and pigs. The viscosity-generating potential and the formation of a physical barrier of these NSP will decrease the feed digestibility of wheat-based broiler diets and, hence, negatively affect broiler performance. This anti-nutritional behaviour of wheat NSP in the GIT of animals led to a negative perception in the feeding industry about wheat as animal feed ingredient over the past decades. However, pressure on the use of antibiotics pushed nutritionists to search for alternative feed ingredients which could maintain the health status of poultry. Based on research and advances in the area of gut microbiota, the view on NSP in the animal feeding industry evolved from them being anti-nutrients to them being at the same time anti-nutrients as well as health- and growth-stimulating fibres, i.e. dietary fibre. Defining and analysing the different types of dietary fibre among animal feed ingredients and their functional value in the GIT of animals is still a major obstacle in the feeding industry. Hence, a better understanding of the functional-structural relationship of wheat NSP is needed.

Presented at the International Fibre Summit 2019 (https://internationalfibre.com/). Reproduced with permission from the organizers.