Highlights of the national compost dairy barn conference
Published in Dairy Star July 14, 2007
This compost dairy barn was seen by conference attendees on the tour at Port-Haven Dairy (Tom and Mark Portner, Sleepy Eye). It was constructed in 2005 and is 54' by 224'. This is their second compost barn; the first was built in 2001.
The University of Minnesota hosted the National Compost Dairy Barn Conference on June 21 and 22, 2007. We had a very diverse audience, with many attendees from out of state and even out of the U.S. (8 different countries). On June 21, most of the conference attendees participated on a tour of 3 compost dairy barns (Portners and Sellners in Sleepy Eye, and Johnsons in Heron Lake), which allowed us to see the system first hand. The producers indicated that they are very satisfied with their compost bedded pack barns, which provide very good cow comfort, and that they have been able to maintain somatic cell counts at low levels. However, they have concerns about cost and availability of bedding material.
On June 22, participants gathered for a full day classroom program. Tom Halbach from the U of M Soil Science Department taught us about composting basics; Russ Bey from the U of M College of Veterinary Medicine shared information on factors affecting bacterial growth in bedding material and how to reduce environmental mastitis; and Kevin Janni from the U of M Bioproducts and Biosystems Engineering Department summarized the layout, design and management of compost barns. Kevin and Russ emphasized the importance of excellent cow prep at milking time in order to make the system work. We all agree on that point!
Bedding alternatives for compost barns was a hot topic during the conference. Stephanie Widmer, graduate student, presented a summary of a study that she and her advisor, Tom Halbach, conducted in their laboratory to investigate various potential bedding options, including beet pulp, corn cobs, corn stover, flax straw, wheat straw, wheat straw processing byproduct, soybean hulls, soybean straw, elm chips, pine bark and pine chips. Based on various laboratory measurements, such as pH, C/N ratio, bulk density, water holding capacity, and carbon dioxide evolution rate, they concluded that pine chips, pine bark, elm chips, corn cobs, soybean straw and flax straw can be potentially used for bedding. It is important to note that the straw and cobs need to be finely processed (about ½ inch long) in order to work. Keith Jacobson from the Minnesota Department of Natural Resources shared with us where in the state wood products can be found, and Alan Doering from the Agriculture Utilization and Research Institute (AURI) told us about potential agricultural byproducts that can be used for bedding. I shared some preliminary results of the bedding alternatives pilot study we are doing at the U of M Research and Outreach Center in Morris using soybean straw, corn cobs, pine chips/shavings, soybean straw/pine chips compared with shavings. It appears that all of these materials can work well in terms of cow cleanliness, cow comfort and udder health.
A session of great interest was our producer panel with Dan Barka, Andrew Golberg, and Tom Portner. They each gave us a virtual tour of their compost dairy barn operation and answered many questions from the audience about their management, satisfaction with the system, etc. I presented results of a field study in Minnesota indicating that performance, welfare and behavior in compost barns was similar or better than other confinement housing systems for dairy cows. Michael Russelle from the USDA Agriculture Research Service (ARS) shared some results of an ongoing study on the fertilizer value and characteristics of compost barn manure. The manure contained 6.2 to 12.2 lb/ton of N, 3.2 to 8.7 lb/ton of P2O5, and 9.7 to 17.8 lb/ton of K2O. The study showed that N concentration was higher than traditional manure suggesting that compost bedded packs retain more of the excreted N per unit mass of bedding. Margot Rudstrom, U of M Regional Extension Educator and Applied Economics Specialist at Morris, described some of the costs and benefits associated with compost barns and how they might compare with sand-based freestall barns. She concluded that economics could probably be similar between the two systems, with one having a higher cost for bedding and the other a higher cost for manure management. But more research is yet needed. Marty Long from Minnesota Mulch and Soil told us that mature compost from compost bedded pack barns is an excellent product to be sold to garden centers and gardeners. He said that city folks are lining up for it! This is a potential marketing opportunity to be investigated by compost barn producers.
I think that the conference was a great opportunity to learn, interact with producers and researchers, and to have a fun time (of course, I am biased). I would like to thank all of you who attended the conference and all of our speakers for a wonderful job.