Wayne Schoper, County Extension Technical Advisor

December 24, 2004

There has been a lot of talk recently about the concept of the "composted bedded pack barn." In the simplest of dairy lingo terms, it is basically a loose housing type of facility bedded down with some choice of bedding material. In most cases the material used is sawdust. Many other materials have been tried but sawdust seems to work the best for dairy producers who have these facilities. The first Minnesota dairy producers to try this approach were the Portner Brothers of rural Sleepy Eye in south central Minnesota. Tom and Mark Portner had read about a dairy producer in the eastern United States who had tried a compost facility and had been very pleased with the results. So after much investigation and discussion, the Portners made the decision to go in this direction. Construction of their facility took place in early fall of 2001 and they had cows in the barn by the middle of October. (See the October 8 Dairy Star article “Composted Bedded Pack Barn Solves Cow Comfort Woes,” for more information.) In the three years since their barn was built several other producers have followed the Portners’ lead and also built similar compost bedded pack barns.

What is so attractive about this housing concept that has inspired so much interest? There are three important factors that come to mind. First of all, cow comfort is unexcelled. The hope that a producer can get an extra lactation or two out of a good cow is important to the long term profitability of the dairy operation. The two other important benefits from compost bedded pack housing are a reduced somatic cell count and higher milk production, factors that are important to every dairy producer.

As a result, now that there is so much interest in these compost barns, the question becomes - "if everyone is building one, will there be enough sawdust to go around?" The answer is yes. There seems to be plenty of sawdust providers around but how much is this sawdust going to cost in the future?

Here are some current economic considerations that are a compilation from four different farms using a compost bedded pack facility.

• First of all, a load of good quality sawdust will cost between $750 and $850 per load. Depending on the time of the year, a load of sawdust will need to be added to the barn compost every three to five weeks. In the winter time or during wet times of the year, sawdust will need to be added more often―sometimes as often as every three weeks. In the summer or during dryer times of the year, a load can last five weeks or more. This is assuming a stocking rate that allows 75 to 90 square feet resting space per cow. This calculates out to $0.35 to $0.60 per cow per day. Using an average of $0.50 per cow space per day, this amounts to $182.50 per cow per year or $13,687.50 for a herd of 75 cows.
• Labor savings on manure handling. Keep in mind that in order for the compost bedded pack concept to work appropriately the pack must be stirred twice a day. This chore usually only takes five to ten minutes. However, when comparing this system to others being used, it can amount to a lot of time saved spent on manure management every year. Also, cleanout is fairly simple since the dairy operator would be dealing with a dry product that can be handled without a lot of expensive equipment.
• Savings due to keeping cows longer. The real benefit from the compost bedded pack housing management concept is the potentially saving on cow replacements. Instead of culling a lot of cows because of feet and leg problems or other barn related health issues, culling can be based on milk production and profitability. Keeping high producing cows in the herd for more lactations can be the norm on the dairy farm. Shipping cows to market because they are injured, can’t walk well and can't use the freestalls anymore could be a thing of the past.

My recommendation would be to check out a couple of these facilities on farms where they are being used before you decide to build. Get some ideas and recommendations on what it takes to make compost bedded pack barns work. Call a member of the Extension Dairy Team for some names and phone numbers of dairy producers using this technology.

(Note: “Compost Barns Basics” will be a topic presented at all eight Minnesota Dairy Day locations to be held January 4 to14. Go to the Dairy Extension web site at: www.extension.umn.edu/dairy/efforts/dairydays2005.htm for the complete agenda and locations. Dairy producers should have received a Dairy Day brochure in the mail.)

Bedded pack is stirred to a depth of about 12 inches twice a day

Compost bedded pack with cement wall separating feed alley with cows at bunk