Somatic Cell Count Challenges for WCROC Organic Dairy Farm
The spring grazing season is off to a slow start this year because of the weather and it has been a challenge for many producers. At the West Central Research and Outreach Center (WCROC) the organic cow herd was put out to pasture the second week of May, about 3 weeks later than normal. However, with some hot and humid weather pastures will soon begin to grow rapidly and will need to be managed properly, including being mowed for hay, so they don't get out of control.
During the past few months, we have had some listening sessions with organic dairy producers. They provided input for future research and extension programming in organic dairy production at the University of Minnesota. One issue consistent across the sessions was how to improve milk quality under organic conditions. Therefore, let us discuss some milk quality information from the past year at the WCROC and tell you what we have done to lower the somatic cell counts for both the organic herd and the conventional herd.
In the table below are the averages for number of cows, milk pounds, and bulk tank somatic cell count from June 2010 to May 2011. Because two-thirds of cows calve in the spring and one-third calve in the fall, cow numbers and milk production for both herds fluctuated during the year. For the organic herd, the somatic cell count (SCC) has been on a roller coaster ride. During September 2010, some cows were culled because of high SCC and those cows were positive for staph aureus. From January to March, the SCC was very high. We were struggling to find out what was happening; however, through extensive culturing we discovered that a third of the organic cows were staph aureus positive. We needed to take action and decided to cull the staph aureus positive cows that had high SCC. This helped to finally get the SCC in the organic herd under control. Recently, the organic herd has had a lower SCC than the conventional herd.
We have experienced the same problems with the conventional herd where some cows had high SCC, some were staph aureus positive, and, therefore, some cows were culled. We have had to learn how to manage staph aureus in our grazing herd, but it continues to be a challenge every day. The lower somatic cell count in the conventional herd comes at greater expense because of the use of antibiotics to treat mastitis.
Many dairy producers are skeptical of organic production because of the restrictions imposed on the use of antibiotics. Organic dairies treat mastitis in a variety of ways, from frequent stripping of quarters to homeopathy to utilization of a variety of organic medications such as garlic or aloe.
There are some key points that an organic producer, and all dairy producers, can consider to improve milk quality in their herd. First, identify subclinical infections and culture cows to determine if the cause of the mastitis is either environmental or contagious. Second, milking hygiene is very important. Make sure to use a pre- and post-dip, and wear latex or rubber gloves while milking. Lastly, develop culling guidelines and either cull chronically infected cows or milk them last.
In the future, my colleagues and I will be looking into alternative mastitis and dry-off strategies to help organic dairy producers improve their milk quality. If you need assistance to improve the SCC on your organic dairy or want more information regarding the organic dairy program at WCROC, contact me at (320) 589-1711 or firstname.lastname@example.org.
For more information about organic dairying, visit the University of Minnesota Extension Dairy Team website at www.extension.umn.edu/dairy.
|Bulk tank averages for milk production and somatic cell count from June 2010 to May 2011 at the West Central Research and Outreach Center.|
|Month||Organic herd||Conventional herd|