How does Hay differ from fresh cut grasses

[Rolliet]

If you have an animal, such as a Horse or rabbit which feeds on Hay, what (if any) nutritional difference is there between "Hay" and "fresh grass". Obviously, Hay is grass that has been sun dried to make it more storable. Are there chemical or protein changes that occur to grass that has been dried into hay? I suspect that as the plant dries some sugars are turned into starch. If you have a reference source with an answer to this question I'd appreciate it.
Thanks

 

[D H]

Hay is not dried grass. Dried grass -- that's straw. Straw is not that nutritious. Hay is typically dried legumes.

 

[jim mcnamara]

Hay undergoes fermentation, starch creation, and other processes during the curing phase.

http://en.wikipedia.org/wiki/Hay

As hay changes due to the action of microbes, drying, sodden storage, time, and so on: the nutritional value changes. Often for the worse. Hay storage varies by species of domestic beastie. Cattle are the most tolerant.
I've seen cattle eat Pampers, quite literally. Makes you wonder what the meat is like...

 

[jim mcnamara]

D H - no. Period. Timothy hay is grass. There is ryegrass also hay - Bromus spp. - ryegrass. Straw comes from oat stem hay usually. And oats are grasses as well.

 

[D H]

jim mcnamara - I guess it depends on where you live. I grew up in dairy country. "Hay" was typically alfalfa or clover. If you didn't want your cows to dry up over winter you fed them that or silage. What you're writing about is what dairy farmers called "horse hay." Dairy farmers considered it to be (barely) a grade above straw, and they would use it as straw if they ran out of straw.

 

[jim mcnamara]

You're correct. Dairies require high protein hay == alfalfa. Where I am (New Mexico) steers get the lowest quality hay, horses and dairy cattle get better quality, protein-wise. We also have milk-a-doras (play on words for maquilodora), that are diary farms just over the border in Mexico. Their hay contracts have completely drained local hay supplies. The Animas river basin produces kilotons of alfafla. It all goes over the border.

The NM diaries down in Caballo and Hatch all have "semis" or hire truckers to get their alfalfa from as far way as Kansas. First cut alfalfa here is ~$12 for a 2-wire bale. When I raised horses prior to NAFTA it was 30% of that, inflation corrected.

Horses, steers and non-milking cows do fine on Timothy hay.

 

[Rolliet]

My question is what are the physical changes (apart from losing water) that occur as fresh grass becomes hay.

 

[Pythagorean]

I think jim answered that in his first reply.

 

[AlephZero]

All the above variations in terminology seem to be american-continent-specific.

IN the UK, "Hay" is made from grass (often from the natural grass flora of the region). "Straw" is the stalks of cereal crops like wheat and barley, after harvesting (also oats, but the UK doesn't grow much of that). We use "corn" as the generic name for those crops, to confuse you even more.

(The UK climate isn't suitable for maize as a food crop, though it is now being grown to use the whole plant as biofuel input.)

But UK dairy cattle are also fed mainly on silage (made from grass), not hay. Before the technology for silage making was widely used, hay was supplemented with linseed, or oil-seed (commonly called "rape" in the UK)

 

[Rolliet]

"Hay", as I am referring to it, is typically grasses harvested before going to seed, which is then left to dry (for several days) and then feed to horses and the like.

 

[256bits]

All the above variations in terminology seem to be american-continent-specific.

IN the UK, "Hay" is made from grass (often from the natural grass flora of the region). "Straw" is the stalks of cereal crops like wheat and barley, after harvesting (also oats, but the UK doesn't grow much of that). We use "corn" as the generic name for those crops, to confuse you even more.

(The UK climate isn't suitable for maize as a food crop, though it is now being grown to use the whole plant as biofuel input.)

But UK dairy cattle are also fed mainly on silage (made from grass), not hay. Before the technology for silage making was widely used, hay was supplemented with linseed, or oil-seed (commonly called "rape" in the UK)

Canadian Hay and silage and straw also agree with the UK version.
An exception would be that hay would mainly include mostly any agricultural plant of the grass family that is harvested before seeding, let to dry, and then bundled into bales or stooks or bunched into a pile for use as a later feed to cattle.