HERFS/AUTUMN BONUS TYDSKRIF 2026

Feed structure for chickens: Why does it matter? Retha Gericke – Product Manager: Poultry When producing poultry feed, the goal is to produce a predictable and constant feed tomeet market and animal requirements in terms of both nutrients and physical structure. The physical structure of feed is very important in chicken nutrition because it influences feed intake, digestion, and consequently production performance. Feed structure can be differentiated by both microstructure and macrostructure qualities, as de- fined in the table below. Table 1: Feed structure terms Term What it means Why it matters Microstructure Intrinsic granulation of each ingredient, especially ground raw material particles (e.g. maize particle size) Directly modulates gizzard activity, starch/protein digestibility, and gut health Macrostructure Final physical form of the complete feed: pellet or crumble diameter/length, percent fines, pellet durability Determines voluntary feed intake, potential nutrient/ingredient segregation losses The microstructure (raw material particle size) affects the macrostructure quality for multiple parameters, such as dust, uniformity, particle size, pellet durability, and hardness. Colour, smell, and taste can also be affected by the physical structure and processing of the feed. Feed structure and particle size affect how every raw material in poultry feed is digested. Chickens’ preference for physical structure depends on age. Younger birds prefer smaller particles and can struggle to ingest large particles such as whole maize or pellets. If the maize particles of mash feed are too coarse, young layer hens coming into peak production may select around these particles, as seen in the picture on the left. The importance of the coarse-to-fine particle ratio in feed for both the intakes and physiological development of chickens cannot be underestimated. Coarse particles in the feed stimulate the gizzard. As a result, the size of the gizzard increases and digestion improves. Whereas if the feed is ground too finely, the fine particles can slip through the upper digestive tract without activating the gizzard. Even in pelleted feed for broilers, it has been proven that feeding coarser raw material particles, such as soybean meal, results in the Herfs/Autumn 2026 BONUS www.agribonus.co.za 28