Understanding Goat Somatic Cell Count (SCC)

Somatic cell count (SCC) is one of the most important indicators of udder health and milk quality in dairy goats. But interpreting goat SCC is different from cows, and many goat owners — and even some vets — apply cow standards to goats incorrectly. This guide explains what SCC means, what is normal for goats, and how to manage it.

What Are Somatic Cells?

Somatic cells are white blood cells (leukocytes) and epithelial cells that are naturally present in milk. They are part of the immune system's defense against infection. When the udder fights an infection like mastitis, it floods the area with white blood cells, causing SCC to rise. SCC is measured as the number of cells per milliliter of milk, expressed in thousands (e.g., "250K" means 250,000 cells per mL).

Goats Are Not Cows

This is the single most important thing to understand about goat SCC. Goats naturally have higher somatic cell counts than cows because goat milk secretion is apocrine — meaning the cells actually shed pieces of themselves into the milk as part of normal milk production. Cow milk secretion is merocrine, which does not shed cellular material.

What Causes High SCC in Goats?

Infection (mastitis)

The most serious cause. Subclinical mastitis (no visible symptoms) can elevate SCC above 1,500K. Clinical mastitis (hot, swollen udder, clumpy milk) causes SCC to spike into the millions. Common organisms include Staphylococcus aureus, Streptococcus species, and coliforms.

Non-infectious factors

• Stage of lactation: SCC naturally rises in late lactation (after 250+ DIM) as milk volume drops. This is normal and not a health concern.
• Heat stress: Hot weather can elevate SCC temporarily.
• Estrus (heat): Does in heat may show a temporary SCC spike.
• Age: Older does tend to have slightly higher baseline SCC.
• Milking frequency: Once-daily milking results in higher SCC than twice-daily, because cells concentrate as the udder fills.
• Stress: Transport, herd changes, or any significant stressor.
• Injury: Bruising or physical trauma to the udder.

How to Test SCC

• DHIA (Dairy Herd Improvement Association): Monthly milk testing through a DHIA affiliate. Samples are sent to a lab for accurate SCC, butterfat, protein, and other component analysis. This is the gold standard.
• CMT (California Mastitis Test): A quick, on-farm screening test. Mix equal parts milk and CMT reagent on a paddle. Gel formation indicates elevated SCC. It is not a precise count but useful for identifying problem does quickly.
• DeLaval DCC or PortaSCC: Portable cell counters that give actual SCC numbers on-farm. More expensive but very useful for larger herds.

Managing High SCC

If SCC is above 1,000K consistently

1. Rule out mastitis first. Do a CMT test on each half. If one half gels and the other does not, that half likely has subclinical mastitis. Send a milk sample for culture to identify the organism and appropriate treatment.
2. Check milking hygiene. Are you teat-dipping before and after milking? Is milking equipment clean? Are you milking in a clean environment?
3. Evaluate stage of lactation. If the doe is past 250 DIM, elevated SCC may just be a natural late-lactation rise. Consider drying her off.
4. Check for physical causes. Udder injury, teat sores, or insect bites.

Preventing high SCC

• Clean, dry bedding — wet bedding is the number one risk factor for mastitis
• Pre- and post-milking teat dip with approved teat disinfectant
• Milk does with clean, dry teats
• Replace milking inflations regularly if using a machine
• Milk out completely at every milking — retained milk promotes bacterial growth
• Dry-off does properly with dry cow therapy if your vet recommends it
• Cull chronically high-SCC does that do not respond to treatment — they are a reservoir of infection for the rest of the herd

SCC and Milk Products

SCC affects what you can do with your milk.

High SCC milk has elevated enzymes (lipase and plasmin) that break down fat and protein, leading to off-flavors and poor cheese yield. Even for soap, extremely high SCC milk may produce inconsistent results.