What Particle Size Should Feed Be Ground To? A Guide by Animal Species

Getting the particle size right in animal feed is not a one-size-fits-all task. Different species have unique digestive systems, and each responds best to a specific grind range. We have seen across our work that improper particle size leads to wasted feed, poor growth, and even health problems. Understanding these differences helps us design better milling processes. At FAMSUN, we focus on delivering equipment that matches these biological needs precisely.

Species-Specific Particle Size Requirements

Pigs need finer grinds when young and coarser grinds as they mature. For piglets, a particle size around 500–600 microns supports enzyme development and nutrient absorption. For grower-finisher pigs, 700–800 microns works well without causing gastric issues. Poultry, especially broilers, perform best with particle sizes between 1,000 and 1,500 microns. Their gizzard naturally grinds feed, so a mix of fine and coarse particles improves digestion and gut health.

Ruminants such as dairy cows and beef cattle require much coarser grinds, typically around 1,500–3,000 microns. Fine particles pass too quickly through the rumen, reducing fiber digestion and increasing the risk of acidosis. We recommend a coarse milling grinding approach for ruminant feed to maintain proper rumen function. In contrast, aquatic species like tilapia and shrimp need extremely fine particles, often below 300 microns for larvae and up to 1,200 microns for larger fish. The milling grinding process must therefore be adjustable across a wide range. Using the wrong grind for any species reduces feed conversion ratios and increases production costs.

How Machinery Settings Affect Grind Quality

The choice of animal feed grinder directly controls particle size distribution. Hammer mills use high-speed rotating hammers to shatter material, producing a wider range of particle sizes. They work well for fine grinding of swine and poultry feed. Roller mills, on the other hand, crush material between two rolls, creating a more uniform particle size with fewer fines. We often recommend roller mills for coarse grinding in ruminant feed and for reducing energy consumption.

But machine type alone is not enough. Screen hole diameter, hammer tip speed, and rotor configuration all change the final grind. For example, a hammer mill with smaller screen holes produces finer particles, but it also increases energy use and reduces throughput. In a roller mill, adjusting roll gap and differential speed gives us precise control over particle size. At FAMSUN, we integrate these parameters into our control systems so operators can switch between species-specific recipes without guesswork. Our SWFP66 series hammer mill and TPSG36 series roller mill are examples of how we apply this knowledge. Choosing the right animal feed grinder and setting it correctly ensures that every batch meets the target particle size for pigs, poultry, ruminants, or fish.

There is no universal particle size for all animals. Each species has distinct requirements that directly affect feed efficiency and animal health. By matching milling grinding parameters and animal feed grinder selection to these biological needs, we help producers achieve consistent, high-quality results. FAMSUN brings decades of practical experience into every grinding solution we offer.