Pigs can eat hay, but they are not ruminants — they cannot efficiently digest the cellulose and fiber that makes hay nutritious for cattle, horses, and goats. The honest answer is that hay is a minor supplement for pigs, not a primary feed source. Understanding what hay can and cannot do for pigs helps you make practical decisions on a small farm where pigs and hay-eating animals often share a property.
Why Hay Is Limited for Pigs
Pigs have a monogastric (single-stomach) digestive system similar to humans. They lack the rumen microbiome that breaks down cellulose into usable energy. When pigs eat hay, most of the fiber passes through undigested — providing gut fill but little actual nutrition. Pigs require concentrated energy from grains, protein from legumes or animal sources, and specific vitamin/mineral supplements that hay does not adequately provide.
A pig fed primarily hay will lose weight, show poor growth, and may develop deficiencies regardless of how much hay it eats. Hay is not a substitute for a proper pig ration.
When Hay Is Useful for Pigs
- Bedding: Hay makes excellent pig bedding — it's absorbent, warm, and pigs enjoy rooting through it. Good-quality hay is wasted as bedding; use lower-quality or weather-damaged hay for this purpose.
- Foraging enrichment: Pigs are intelligent animals that root and explore by nature. Scattering hay in their area encourages natural foraging behavior and reduces boredom-related destructive behavior.
- Pregnant sow nesting: Sows given hay to nest with before farrowing show reduced stress and better maternal behavior. This is a legitimate and well-documented use of hay for pigs.
- Minor supplement during pasture access: Pastured pigs on good quality mixed legume-grass pasture get some nutritional value from the legume content. Hay in this context is a very minor supplement, not a ration component.
If Pigs Will Eat Hay, What Type?
If you're offering hay to pigs as enrichment or supplement, alfalfa or mixed legume hay provides the most digestible nutrition due to its higher protein and lower fiber content compared to pure grass hay. Pigs are typically more willing to eat leafy, palatable alfalfa than stemmy grass hay. Keep amounts small and never reduce grain rations in exchange for hay feeding.