Mash is the most basic physical form of chicken feed: a loose, flour-like mixture of ground grains, protein meals, vitamins, and minerals that has not been compressed or heated into pellets. Think of it as the raw recipe, milled and blended but otherwise left alone. It is the starting point for every other feed form, since pellets and crumbles are simply mash that has been steam-conditioned and pressed through a die. Whether mash is the right choice for your flock depends on the birds’ age, purpose, and environment, and the answer is less straightforward than many feeding guides suggest.
How Mash Differs From Pellets and Crumbles
All commercial chicken feeds begin as mash. The ingredients are weighed, ground through a hammer mill, and mixed together. At that stage the feed is mash, a fine-to-coarse powder with a range of particle sizes. To make pellets, manufacturers push that mash through a pellet die under heat and pressure, producing uniform cylinders usually a few millimeters across. Crumbles are pellets that have been broken back down into coarse granules, giving young chicks something easier to pick up than a full pellet but more uniform than raw mash.
The processing distinction matters because heat and compression change more than just the shape of the feed. Pelleting gelatinizes some of the starch in grains, which can alter how quickly the bird digests it. It also binds the various ingredients together, so a bird eating a pellet gets the full nutrient package in every bite rather than being able to pick through for favorite particles. The trade-off is cost: running a pellet mill takes energy, and the conditioning step adds manufacturing expense. As one feed-processing study noted, total manufacturing energy costs go up even when individual pellet-mill energy costs drop with newer equipment.
Why Mash Still Has a Place
Given that pellets tend to outperform mash on paper, you might wonder why anyone feeds mash at all. There are several real advantages.
First, mash encourages birds to spend more time eating. Because the particles are small and varied, chickens peck at the feed more slowly and for longer stretches. Research on laying hens found that birds fed mash had longer feeding bouts and higher rates of pecking at the food compared to birds on pellets.1PubMed. Effect of foraging material and food form on feather pecking in laying hens That extended feeding time doubles as foraging enrichment. Hens in that study used the mash not just for eating but as a substrate for natural foraging behavior, scratching through the feed trough the way they would scratch through soil. The practical payoff was a reduction in feather pecking, a costly welfare problem in laying flocks. High rates of feather damage were only seen in hens housed without straw and fed on pellets, suggesting mash can serve as a kind of behavioral buffer.
Second, mash is the cheapest form to produce. Because it skips the pelleting step entirely, small farms and backyard flock owners can mix their own mash from locally sourced grains without specialized equipment. For operations that already pay for commercial feed, mash is typically priced lower per ton than pellets.
Third, mash supports gizzard development. The gizzard is the muscular organ that grinds food before it passes into the intestines. Birds fed mash diets develop heavier gizzards than those fed pelleted or crumbled diets. One broiler study found that the relative empty weight of the gizzard was significantly greater in birds fed mash than in those fed crumble-pellet diets.2PubMed Central. Effects of feed form and feed particle size on growth performance, carcass characteristics and digestive tract development of broilers A well-developed gizzard does a better job of mechanically breaking down feed, which can improve nutrient extraction over the bird’s lifetime.
Performance Differences in Broilers
For meat birds raised for fast growth, pellets and crumbles consistently outperform mash on the metrics that matter most to commercial producers: body weight gain, feed intake, and how efficiently birds convert feed into meat. A trial comparing fast-growing broilers on mash versus pellets found that pelleted birds had roughly 19% higher final body weight, about 12% higher feed intake, and a 12% better feed conversion ratio.3Journal of Applied Poultry Research. Short- and Long-Term Effects of Feed Form on Fast- and Slow-Growing Broilers Those are large differences. Interestingly, the same study found that slow-growing breeds showed no significant difference in feed intake or body weight gain between pellets and mash, though feed conversion still improved slightly with pellets.
Another trial looking at the first three weeks of life confirmed the pattern: body weight and feed conversion were both significantly better in broilers fed crumble-pellet diets than in those fed mash throughout the starter period.4PubMed Central. Effect of Crumble-Pellet and Mash Diets with Different Levels of Dietary Protein and Energy on the Performance of Broilers at the End of the Third Week The reason is partly mechanical. Birds eating pellets spend less time and energy physically picking up food, leaving more energy available for growth. Pellets also eliminate the selective feeding problem, where birds sort through mash for the tastiest or most visible particles and leave the rest.
That said, not every situation calls for maximum growth speed. Heritage breeds, pasture-raised birds, and backyard flocks are often managed differently, and the performance gap narrows or becomes less relevant when birds are not being pushed toward a market weight on a tight schedule.
How Feed Form Affects Laying Hens
The story for egg-layers is more nuanced than for broilers. A study comparing pellet and mash diets across two laying hen breeds found that pellets improved laying rate, egg weight, shell strength, and interior egg quality in both breeds.5PubMed Central. Effect of the Pellet and Mash Feed Forms on the Productive Performance, Egg Quality, Nutrient Metabolism, and Intestinal Morphology of Two Laying Hen Breeds The birds on pellets also digested dry matter and crude protein more efficiently. On the surface, that looks like a clear win for pellets.
But a separate study complicates the picture. Hens fed mash had about 2.3% higher feed consumption than those on pellets, and the researchers suggested the hens may actually prefer mash.6Canadian Journal of Animal Science. Effect of feed form, formulation, and restriction on the performance of laying hens The same study found that formulating the diet based on total protein content rather than specific amino acids boosted egg production and egg mass in hens on mash. In other words, a well-formulated mash diet can close a meaningful portion of the performance gap. For small-flock owners who value bird welfare and natural behavior alongside production, mash remains a solid choice for layers, especially given the behavioral benefits around feather pecking described earlier.
Feed Waste and the Segregation Problem
One of the most practical downsides of mash is waste. Because the particles are small and loose, birds flick feed out of troughs more easily, and fine powder settles at the bottom where birds may ignore it. Broilers fed crumbles wasted less feed than those fed mash regardless of the conditioning temperature used during crumble production.7Journal of Applied Poultry Research. Effect of feed form, energy level, and conditioning temperature on broiler performance, feed wastage, and nutrient digestibility from 1 to 21 days-of-age The reduction in waste is generally attributed to less selective feeding and fewer particles falling from the beak.
There is also the issue of segregation. Mash contains a wide range of particle sizes, and those particles tend to separate during transport through auger or chain delivery systems. Research documented two main segregation patterns: sieving, where small particles fall through spaces between larger ones, and side-to-side segregation during delivery.8Journal of Applied Poultry Research. Effect of Feed Segregation on the Commercial Hen and Egg Quality The result is that hens at different positions along a feed line can end up eating diets with significantly different nutrient profiles, even though the feed started out properly balanced. For backyard keepers filling a single feeder, segregation is less of a concern, but for anyone running a longer feed delivery system, it is a real nutritional risk.
Pelleting and crumbling largely eliminate both problems. The particles are bound together so they cannot sort during delivery, and their larger size means less spillage. This is one reason commercial operations overwhelmingly prefer processed feed forms despite the higher cost.
Selective Feeding and Flock Uniformity
When birds can pick through mash, they tend to favor certain ingredients. Corn particles are often preferred over finer protein meals, and the more dominant birds in a flock may eat their fill of the energy-dense grains while less assertive birds get what is left. This produces uneven nutrient intake across the flock, which shows up as poor body weight uniformity. Research on broilers confirmed that pelleting and crumbling reduced the impact of selective feeding and produced more consistent feed intake across the flock, while coarse corn in mash diets stimulated gizzard weight in a linear manner as particle size increased.9PubMed. Effects of feed form and dietary coarse ground corn on broiler live performance, body weight uniformity, relative gizzard weight, excreta nitrogen, and particle size preference behaviors
This is a genuine tension in mash feeding. The same particle-size variation that promotes gizzard health and natural foraging also enables sorting behavior that works against uniform nutrition. If you feed mash and notice that some birds in your flock are growing noticeably faster than others, selective feeding is a likely culprit. One practical workaround is to add a small amount of water or oil to the mash so it clumps slightly, making it harder for birds to pick out individual ingredients. That approach leads naturally to the topic of wet mash.
Wet Mash Feeding
Mixing mash with water creates wet mash, sometimes called a “porridge” feed. This is a time-honored practice in small-scale poultry keeping, and it has measurable benefits in certain conditions. A trial conducted in a hot climate found that broilers fed wet mash ate about 174 grams per day compared to 152 grams per day for those on dry mash, and gained about 64 grams per day compared to 58 grams for the dry-fed birds.10PubMed. Effect of wet feeding on growth performance of broiler chickens in a hot climate Feed efficiency was the same across groups, meaning the birds were not just eating more and wasting it. They were eating more and growing proportionally more.
The likely explanation is straightforward: in high temperatures, birds reduce feed intake to avoid generating metabolic heat from digestion. Wet feed is easier to swallow and may generate less heat during digestion, helping the birds maintain intake when they would otherwise back off. That same study found that feeding wet mash only during the hotter daytime hours and switching to dry feed at night produced results just as good as wet feeding all day, which is practical because wet mash spoils faster than dry. In warm climates or during summer heat waves, wetting a portion of your mash can be a simple, effective tool.
The spoilage caveat is real, though. Wet mash left in a feeder for more than a few hours in warm weather can grow mold and bacteria. The standard practice is to offer only as much wet mash as the birds will clean up within 20 to 30 minutes and remove any leftovers promptly.
Fermented Mash
Taking wet mash a step further, some poultry keepers ferment their mash by soaking it in water for one to three days, allowing naturally occurring lactic acid bacteria to proliferate. This is not a fringe practice; it has genuine science behind it. A review of fermented feed research found that fermentation enhances nutrient availability, reduces compounds that interfere with digestion, and generates short-chain fatty acids that support gut health.11PubMed Central. Effect of Fermented Feed on Growth Performance and Gut Health of Broilers: A Review The fermentation process also increases populations of beneficial lactic acid bacteria while reducing harmful microbes.
For backyard flock owners, fermented mash is an accessible way to squeeze more nutritional value from the same feed. The process is simple: submerge mash in water, keep it covered, stir once or twice daily, and feed the resulting slightly sour slurry after a couple of days. You maintain a rolling batch, adding fresh mash and water as you scoop out fermented feed. The birds generally take to it readily, and the mild acidity of the fermented mash may help suppress Salmonella and other pathogens in the gut. The downside is the extra daily labor and the need to manage the fermentation so it stays aerobically clean on top (mold on the surface means the batch is compromised).
Particle Size in Mash Matters More Than You Might Think
Not all mash is ground to the same fineness, and the particle size has real consequences. Very fine mash, ground to a powder, is harder for birds to eat, more prone to bridging in feeders, and tends to produce more dust. Coarser grinds are easier for birds to pick up and, as mentioned earlier, stimulate gizzard development. A study on young broilers in the starter phase found that body weight gain and feed conversion could be maximized by feeding an average particle size of roughly 2,800 micrometers or greater during the first two weeks.12Journal of Applied Poultry Research. Increasing Average Feed Particle Size During the Starter Period Maximizes Ross × Ross 708 Male Broiler Performance That is a fairly coarse grind, closer to cracked grain than to flour.
The same study on mash particle sizes in broilers confirmed that medium and coarse particle sizes produced higher body weight, daily gain, and daily feed intake than fine particle sizes across the full growing period.2PubMed Central. Effects of feed form and feed particle size on growth performance, carcass characteristics and digestive tract development of broilers So if you are buying or mixing mash, coarser is generally better than finer, within reason. When mash is ground too coarsely, birds can sort individual grain fragments from the protein and mineral components, bringing you back to the selective feeding problem. There is a sweet spot where the grind is coarse enough to support gizzard function and feed intake, but not so coarse that the birds can easily pick it apart.
Pathogen Safety and the Heat Advantage of Pellets
One underappreciated difference between mash and pellets is microbial safety. The steam conditioning and die compression involved in pelleting expose feed to temperatures that kill a significant portion of bacteria. A recent study pelleting mash broiler feed at temperatures ranging from 70 to 85°C found that pelleting at 80 or 85°C reduced Salmonella surrogate populations the fastest, and it took at least 50 seconds at those temperatures to achieve a meaningful reduction in bacterial counts.13PubMed Central. Thermal Inactivation of Salmonella Surrogate, Enterococcus faecium, in mash broiler feed pelleted in a university pilot feed mill Mash, by contrast, never sees those temperatures, so any Salmonella or other pathogens present in raw ingredients remain viable.
This does not mean mash is inherently dangerous. Most commercial feed ingredients undergo their own safety treatments, and good storage practices go a long way. But in contexts where biosecurity is critical, such as after a regional disease outbreak or on farms with a history of Salmonella issues, the thermal kill step in pelleting provides an extra margin of safety that mash simply cannot match.
The Role of Fiber Sources in Mash Diets
Mash diets offer more flexibility for incorporating structural fiber, which is increasingly recognized as beneficial for broiler gut health. A large-scale trial with over 4,000 day-old broilers tested seven different fibrous ingredients as replacements for a small portion of the wheat in the diet. Oat hulls improved feed conversion over the full growing period compared to most other fiber sources, while beet pulp reduced body weight and feed intake relative to oat hulls.14PubMed Central. Evaluation of fibrous feed ingredients alternatives to oat hulls as a source of feed structure in broiler diets The practical takeaway is that adding a small percentage of the right fibrous material to a mash diet can improve performance, but not all fiber sources are equal. Oat hulls are a well-established choice; alternatives like soy hulls, wheat bran, and rice hulls can work but may not match oat hulls’ consistency.
For backyard flock keepers who mix their own mash, this is useful context. Tossing in whatever fibrous scraps are available is not the same as choosing a fiber source that complements the diet. If you have access to oat hulls from a local feed supplier or brewery, incorporating a small proportion into a homemade mash is a straightforward way to support gut structure without complicating the overall nutrient balance.
When to Choose Mash Over Pellets
The research consistently shows pellets and crumbles outperform mash on production metrics, so the decision to feed mash is usually driven by factors beyond raw efficiency. Mash makes the most sense when you are managing laying hens in systems where feather pecking is a concern, since the extended feeding time doubles as behavioral enrichment. It also suits situations where cost matters more than maximizing growth speed: heritage breeds on pasture, backyard flocks kept for eggs and companionship, or small farms that mill their own grain. Hot climates are another scenario where wet mash can meaningfully improve feed intake compared to dry alternatives.
Conversely, if you are raising commercial broilers on a schedule where every gram of feed conversion matters, or if you are running a long mechanized feed delivery system where segregation would skew nutrition, pellets or crumbles are the better tool. Many producers use a hybrid approach: crumbles for the starter phase when chicks are too small to handle full pellets, then pellets from the grower phase onward, occasionally incorporating coarse mash elements to promote gizzard health.
Understanding what mash actually is and how it compares to processed forms puts you in a better position to match your feed choice to your flock’s real needs rather than defaulting to whatever the feed store stocks most of. The “best” feed form is always the one that fits the birds, the management system, and the goals of the person running the operation.