Why does Somatic Cell matter to a dairy farmer?
Somatic cell testing is an economical tool to provide dairy farmers (whether one cow or 10,000) with measurable monitoring records of a cow’s udder health.
High somatic cell is an indicator of infection and often sub-clinical mastitis can be diagnosed earlier by recognizing high numbers on a routine test.
High somatic cell count can damage milk secreting tissue and reduce milk production ability in the udder.
What is Somatic Cell?
SCC (Somatic Cell Count) – Somatic Cells are white blood cells, mostly leukocytes, that are an indicator of infection. (The higher the number, the more the body’s defense system is attacking some sort of infection.) Most often written as thousands (-,000). For example: if you see “45″ it really means 45,000 somatic cells per ml.
In general, SCC below 200 (200,000) is considered healthy. Notice the record (to the right). The cow was healthy on her first test (45/2) and then jumped (966/6). She showed no outward signs of mastitis, but obviously had some sort of health issue flare up that should be addressed. A count over 1 million should be diagnosed immediately through bacterial culturing. Counts above 500+ should be monitored and considered for further diagnostics.
The legal limit for bulk milk sold commercially is 750 (,000). Hoards
SCS (Somatic Cell Score) is a number from zero + and takes the SCC and puts them into ranges from low to high. For example: next to the “45” under SCC is “2” for SCS. A count of 4 or less is considered healthy. Counts 6 or higher should be considered for further diagnostics.
Often, late in lactation when a cow has been milking 9+ months, her somatic cell may rise significantly. It should still be in the “healthy” range (under 250k-ish) but may be a lot higher than the cow normally tests.
How can I get a test done for my cow?
State DHIA labs test routinely for Somatic Cell. For dairy farmers with less than 10 cows, monthly herd monitoring through DHIA can be fairly expensive.
For those with only a few cows or less, we recommend sending off your own samples to a lab.
An example of a lab that tests for somatic cell is Udder Health Laboratories in Washington state: http://www.udderhealth.com/services.htm
Be sure to read online instructions or call the lab before sending samples, so the samples are not collected with contaminants.
CLICK HERE for more information on milk testing and laboratories.
Is Somatic Cell testing different than testing milk for bacteria?
Yes and no.
SCC is a concrete indicator of udder health and, in our opinion, is the most useful milk testing tool for monitoring general udder health.
When sending milk to be cultured (or DNA tested) the tests are limited to information on if pathogenic bacteria are present, and if so, to what level. The problem with cultures/DNA is contamination. Submitting a sample requires utmost cleanliness, and even then sometimes contamination occurs (and scares the cow owner, thinking their healthy-looking cow is a time bomb!)
- somatic cell for monitoring
- bacterial culture for specific diagnosing (for a cow showing signs of mastitis, a cow being prepared to go dry, etc.)
Somatic cell readings can vary over time and lactations. This is fine, it’s more important to monitor for extremes – like going from a average of 50 to a reading of 1,000 (meaning, one million).
Average SCS over several lactations. Each line represents one completed lactation:
SCC and SCS for one cow during one lactation. Each line represents one month’s DHIA sample test: