Posted 5/21/2020 11:04 (#8271352 - in reply to #8271115) Subject: RE: Teach me about sawdust barns for beef...
I do not have any experience with growing animals on sawdust. I do manage a dairy herd on a compost bedded pack. This is a mixed herd, about half Holstein and half Jersey. The feed alley is along one side of the pack, the feed lane is flushed twice per day. We use kiln-dried shavings, added as needed. When the pack starts getting a little too damp, we add shavings. Usually bed about once a week during winter, using about 1/3 of a live-bottom load each time we bed. This time of year we won't need to bed nearly as much, maybe once a month. We have fans on continuously, and one side has a curtain that is down in the cooler months. The fans keep air moving and help to dry it out. We plow twice per day with what is known locally as a "rooter", I have heard them called re-breakers or orchard plows. We have used a tine- tiller, but the one we have doesn't get deep enough to let air into the pack to encourage composting. We went 18 months between cleanout last time, could have went longer but we had time to clean it out and had available shavings to re-bed at that time. We start out after clean-out with about half new shavings mixed with the cleaned out compost, start out with about a foot deep bedding. It does require some management, but it works well.
I think you could make growing livestock work in a compost pack. I think if you kept the space per pound of animal close to 1ft/10lb,(100 ft square for 1000lb cow) that would work. If you have the bedding, if you have the ability to manage it by plowing often and bedding as needed. I think the system would work. I don't know that you can make the economics work. The cost of the building and concrete, the cost of the bedding, the cost of the electricity for the fans, the cost of a tractor and plow dedicated to multiple times per day plowing, and the cost of management and labor to get it all done. All of this adds up pretty fast. I don't know your numbers and how available your bedding source is, so I can't do the simple math. The composting is what makes our system work, without the fans, plow, and bedding source, we would just have dirty cows and a lot of wet manure and bedding that would need to be cleaned out often.