Compost Dairy Barns – Summer 2007 Update
Published in Dairy Star July 28, 2007
The University of Minnesota hosted the National Compost Dairy Barn Conference in late June. The conference featured a full day of tours to visit three barns in South-Central Minnesota followed by a day of presentations discussing the latest research and techniques for managing these new style of barns. The attendance for both days was excellent with participants from many different states and foreign countries, including Brazil, Canada, Chile, Germany, Israel, Japan, and the Netherlands. The age of the Internet is truly amazing as many of these folks had discovered the University of Minnesota website that was promoting the conference. All of the conference participants had one goal in mind, to create an environment where their cows would be comfortable and also produce quality milk.
So what is the status of compost bedded pack barns at this time in the summer of 2007? Compost bedded pack barns have been around for a few years now and producer interest has been very high. The lure of unmatched cow comfort and cow longevity has intrigued everyone associated with the dairy industry. But is it a realistic option?
Following are some observations made by myself and others during the recent tours:
- What are some of the management issues associated with the compost bedded pack barns? What has been a constant concern and has remained on the forefront as we gain more experience and knowledge is that excellent udder prep is paramount to successfully controlling mastitis and keeping somatic cell counts under control. There are a lot of bacteria on the surface of the pack and this will show up on the udders of the cows as they come into the milking parlor. However, we all know that there are a lot of bacteria around in any dairy housing situation and good udder prep needs to be a primary fundamental for all dairy farms. On the tour, we did find out there are several ways to manage the pack. Compost barn owners don’t necessarily have to stir it twice a day. They can experiment with when and how much material to add to the pack to keep it fresh. It was also observed that every farm handles their cows and barn management differently. This tells me there can be some flexibility in cow and barn management that is not always present in other systems. Also on the tour was a person who was taking temperatures down in the pack. The temperatures varied widely with a range of 90° F up to 150° F. These temperatures are a little low for true composting to occur. However, we do know that a lot of heating does occur during the summer months and that the material coming out of the barns at cleanout in the fall is a fairly consistent product and is ready to apply to fields to fertilize next year’s crop.
- What can be done to ensure a steady, economical supply of sawdust or other bedding material to make these barns work? This was the question of the day on the tour and an issue that was discussed at the conference session. Just about everyone who sees these barns is in agreement that the cow comfort excels any other housing option they have seen. The problem is that sawdust suppliers have experienced an increased demand and the price of sawdust has begun to rise accordingly.
The University of Minnesota is conducting research to help answer this question. However, producers that own these barns are taking the bull by the horns and doing some research themselves to see what other options will work. At least one producer is using a combination of sawdust and finely chopped soybean straw and mixing this together as one possible option. He has been doing this for the past several months and it seems to be working well. The problem is getting the soybean residue chopped finely enough to be mixed and tilled together with the sawdust. One idea is to send bales of soybean straw back with the sawdust provider to chop the straw and mix it with the sawdust and bring it back with the next load. Current sawdust prices are around $950 per semi-load and this option will reduce that by 30-35%. There have been a lot of other potential bedding materials experimented with but nothing can beat sawdust or combination thereof for tilling and manure adsorption.