With cull cow prices relatively strong, the no-brainer way to reduce somatic cell counts (SCC) is to call your trucker and send those high-count cows on down the road.
Well, maybe. A few extremely high-cell-count cows removed from the tank can and will have an immediate effect on your bulk tank average. But if you don't find the source of the problem, your bulk tank SCC average could creep back up in short order.
The first order of business in getting cell counts under control once and for all is to acknowledge you have a problem. Seek help—from your veterinarian, milk plant field man, milk equipment dealer and a qualified milk quality consultant.
Using a team approach often works best, says Jeff Reneau, a University of Minnesota veterinarian and milk quality specialist.
Then, determine if you have a cow problem or a systemic herd problem. "You first need monthly individual cow somatic cell counts,” Reneau says. "Then you can determine if you have just a few chronic high cows or whether you have a herd problem.
"If you have a high percentage of cows that are above 400,000 cells/ml but not exceptionally high, you need to do some major sanitation work. You'll likely need to improve bedding management and cow milking prep procedures,” he adds.
By screening cows monthly for SCC, you can begin to tell when new infections occur. Do they occur mostly in fresh cows or across the lactation?
Once you've identified the problem cows, you'll need aseptic quarter samples from these animals to determine the bacteria you are dealing with, explains Joe Hogan, a milk quality specialist with The Ohio State University.
When high cell counts are the problem, Staph. aureus and Strep ag. bacteria are the usual suspects. Milking time sanitation and teat dipping are critical to stopping cow-to-cow spread. Older chronically infected Staph. cows are immediate cull candidates to both eliminate their SCC contributions and infection threat to herdmates.
If the culprit is environmental mastitis, stall and bedding management become critical. Replace all organic bedding in every stall every week. Every day, replace the bedding in the back half of stalls with fresh bedding.
If sand is used, rake manure from stalls each milking and add fresh sand at least weekly. Also double check premilking cow prep to ensure you are attaching units to clean, dry teats that have been properly stimulated for let down.
Minnesota DHIA records indicate that an average 35% of cows and heifers calve with high cell counts, Reneau says. To prevent new infections at calving, treat all quarters of all cows at dryoff with an approved dry cow tube. Consider using a dry cow teat sealer.
- June/July 2010