Two feeds with the same formulation can result in different feed conversion ratios (FCR), average daily weight gains, and flock uniformity. The reason lies not in the chemical composition, but in how that composition is delivered to the birds. Feed form and structure are determined by the production technology, so let us examine it in detail.

The pelleting process is a sequence of mechanical, hydrothermal, and physicochemical effects on the raw materials. An error at any stage reduces the quality of the finished product and PDI (Pellet Durability Index).

Grain ingredients (corn, wheat, barley) are ground in hammer or roller mills. The degree of grinding is crucial: excessively fine grinding impairs gizzard development, while excessively coarse grinding reduces pellet durability.

Dosing and Mixing of the Feed Mixture: ground grain is dosed according to the formulation and thoroughly mixed with protein components (meals, oilseed cake), minerals, amino acids, and dry premixes to achieve high mixture uniformity.

The dry mixture enters the conditioner, where dry saturated steam is supplied under pressure (2–4 bar). The feed is heated to 70–85 °C (in long-term conditioners or expanders — up to 85–90 °C), while moisture increases by 3–5%. This is a key stage for starch gelatinization, protein plasticization, and mass sanitation.

The moistened and heated mass is fed into a pellet mill, where press rollers force it through the holes of a ring or flat die. Under high pressure and friction, feed particles tightly bind together, forming continuous strands that are cut by knives into pellets of the required length.

Hot, moist pellets enter a counterflow cooler. By blowing dry air through them, the pellet temperature is reduced to a level no more than 5 °C above ambient temperature, while moisture is reduced to a safe 12–13%. This stabilizes the structure and ensures long-term storage without mold formation.

For starter chicks, cooled pellets with a diameter of 3–4 mm are passed through a crumbler to obtain crumbles of the optimal size (1.5–2.5 mm).

The product passes through a vibrating screen, where the dusty fraction is removed. This off-spec residue is returned to the pellet mill for re-pelleting.

To preserve heat-sensitive substances (fats above 1.5–2%, liquid enzymes, vitamins, probiotics), liquid ingredients are sprayed onto the surface of already cooled pellets or crumbles using nozzles or under vacuum.

To preserve heat-sensitive substances (fats above 1.5–2%, liquid enzymes, vitamins, probiotics), liquid ingredients are sprayed onto the surface of already cooled pellets or crumbles using nozzles or under vacuum.

Grain raw materials (corn, wheat, barley) in their pure form contain 60% to 72% starch. In finished broiler feed (after adding meals, oil, and minerals), its proportion is 35–45%.

In their raw (native) state, starch granules have a dense crystalline structure that is difficult for the bird’s digestive enzymes (amylases) to access.

With mash feed, birds select larger grain particles, leaving the fine fraction at the bottom of the feeder. This fine fraction contains vitamins, minerals, and crystalline amino acids. As a result, actual nutrient intake deviates from the calculated values, and flock uniformity decreases. Pellets and crumbles lock the full nutrient balance into every particle.

Conditioning partially gelatinizes starch and reduces bacterial contamination (including Salmonella and E. coli).

Grasping a pellet or crumble requires significantly fewer beak movements and less time than consuming mash feed. As a result, the conserved energy is directed toward live weight gain rather than mechanical work.

During vibration in augers and feed trucks, mash feed separates according to particle density and size. Pelleted feed maintains composition uniformity.

Pellets do not become airborne dust in the poultry house. This reduces feed losses through ventilation and lowers the risk of respiratory diseases in the flock.

The benefits of pelleted feed are maintained only when it reaches the feeder intact. PDI (Pellet Durability Index) measures the percentage of pellets that remain undamaged after standard mechanical testing (for example, in a Holmen tester or TUMBLER tester).

• If PDI is low (< 85–90%), pellets break apart in the feed delivery line. The birds effectively receive mash feed, even though the farm has paid the full cost of pelleting.
• For broiler feed, the target PDI should be at least 90–92% (for finisher feeds — preferably up to 95%).

Pelleting adds 3–5% to the cost of a ton of feed (steam, electricity, and die wear costs). However, a 4–8% improvement in feed conversion (FCR), increased average daily gains, and maintained flock uniformity outweigh these costs, making pelleted feed the most effective solution in modern broiler production.