There is someone who makes silage for their chickens:
I can't find it now, but someone else did pretty much what the second video did, but they manually cut it into smaller pieces, and used gallon zip-loc bags.
do be sure you eliminate all of the air, so it doesn't spoil. I do want to do this - but with the f/t job and part-time teaching on top of my farm, I haven't implemented it yet. My goal the first year I try it is to have lots of small bags, and put them into a metal covered garbage can ( to keep vermin out) and try feeding a bag a day in the winter to give them greens/supplement. Hopefully I can do this next year!!!!
Some haylage info
https://www.ontario.ca/page/hay-haylage-and-treated-hay-horses
a few infusions of antibiotics, breathing treatments, new effective meds, smart doctors, and pretty nursing staff. 
