Chicken feed particle size is often overlooked by poultry producers because, unlike nutrients or feeding instructions, it’s not listed on the feed tags. However, it’s not enough to assume your feed mill is delivering a consistent, well-balanced ration. If the feed isn’t the right size for your livestock’s age or digestive system, your results—and your bottom line—will suffer.
Why Particle Size Matters in Broiler Poultry Feed
When raising broilers, feed particle size influences physical development and digestive function, shaping traits like beak formation, gizzard strength, gut structure, and nutrient absorption. Larger particles remain in the gizzard for a longer period, which enhances gut motility, increases nutrient absorption in the upper digestive tract, and supports a healthier microbiota—all essential for optimal growth and feed conversion.
Conversely, a small particle diet—especially one with too many fines—can backfire. These particles move too quickly through the digestive system, limiting nutrient absorption and contributing to smaller gizzards, enlarged proventriculi, and poor gut health. Fines can also accumulate in feeders, causing birds to pick out larger particles and miss key nutrients like vitamins and amino acids.
Broiler Feed Size by Growth Stage
Broiler feed size should evolve with the bird’s age. Chicks typically start with crumbled feed (1–3 mm) made from finely ground ingredients, which provides a balanced nutrient bite in every crumb. However, continuing this texture for too long stunts gizzard development and reduces the length of the small intestine.
After the starter phase, a well-textured mash diet is ideal. This includes 55–85% of particles between 1 and 3 mm, with a geometric mean diameter (GMD) around 1200 microns. Research shows that gradually incorporating more coarse corn or whole grains improves feed efficiency and supports gut health without compromising carcass quality.
Replacing 50% of fine corn with coarse corn (1359 μm) improves nitrogen and energy digestibility, increases feed efficiency, and reduces nitrogen in litter by 8.47%, helping to prevent issues such as footpad dermatitis.
Roller Mill vs Hammer Mill: Getting the Right Grind
How feed is ground directly impacts its effectiveness. The two most common tools for the job are roller mills and hammer mills, and they produce very different results.
Hammer mills grind feed using rotating hammers and impact force. They’re versatile and can process fibrous materials, such as wheat by-products. However, the resulting particle sizes are less consistent. Hammer mills tend to produce more fines and a wider range of particle sizes, which can hurt feed uniformity in broiler feed.
Roller mills, on the other hand, compress and shear feed using rotating rollers. These mills produce a more uniform feed particle size and tighter distribution, making it easier to hit precise broiler feed size targets. This consistency is especially valuable when producing mash diets, where uneven particle distribution can lead to nutrient segregation and selective eating.
If you’re aiming for more control over your broiler poultry feed, a roller mill is your best bet. Not only does it reduce fines, but it also delivers better mixing characteristics and more efficient batching downstream.
Delivery Systems and Feed Separation
Even the best-formulated feed can fall short if it’s not delivered properly. Chain, auger, and hopper feeders all influence how feed particles separate in the trough. Chain feeders can grind particles and push fines to the center, while auger systems cause top-to-bottom segregation. Hopper feeders tend to preserve particle integrity best.
Managing feeding frequency and feed depth can also influence how birds consume different particle sizes. Leaving a 2–4 hour gap midday allows birds to clean feeders and consume accumulated fine particles, ensuring more balanced nutrient intake.
Striking the Right Balance
For poultry producers, adjusting feed particle size isn’t just a nutritional decision—it’s a matter of economics. With feed costs accounting for 60–70% of total production expenses, even slight improvements in grind consistency can lead to significant savings.
What to consider with finer grinding:
- Improves enzyme access and nutrient breakdown
- Increases processing time and energy use at the mill
- Reduces overall throughput
- Can cause flowability issues in silos, bins, and feeders
- Leads to higher moisture loss during handling and storage
- Adds up to significant inefficiencies in large-scale operations
Advantages of using coarser particles:
- Reduces the need for excessive grinding
- Lowers power consumption and processing costs
- Improves feed flow through automated delivery systems
- Minimizes fines that accumulate in feeders
- Promotes more consistent feed intake across the flock
There’s also a less obvious—but important—biosecurity benefit. Coarse particles stimulate reverse peristalsis in the gizzard, increasing acid production and lowering pH. That shift creates an inhospitable environment for pathogens like Salmonella and Clostridium perfringens, helping protect birds and preserve flock health.
Ready to Fine-Tune Your Feed Strategy?
Improving feed particle size doesn’t require an overhaul of your operations—It just requires the right tools. Whether you’re transitioning to mash diets, reducing fines, or aiming for more consistent broiler feed, RMS can help you choose the roller mill solution that fits your operation.
Request a quote or contact us for expert assistance in selecting the roller mill that best suits your operation.
