Every load of milk you sell comes back as a report full of acronyms. Most farmers file it and move on. Learn to read it and it becomes an early-warning system — it tells you about problems days before they hit your milk cheque or your cows.
Somatic Cell Count (SCC) — udder health Mostly white blood cells; the higher it is, the more your cows are fighting infection (subclinical mastitis). Target under 200,000 cells/mL; most buyers penalise over 400,000. A rising trend means mastitis is spreading silently — act before it's clinical. (See "How to lower somatic cell count.")
Total Bacterial Count (TBC) / Total Viable Count / Bactoscan — hygiene & cooling How many bacteria are in the milk. This is about cleanliness and cooling, not the cow. Target very low (often under 20,000–50,000 cfu/mL depending on your scheme). A high TBC almost always means one of three things: 1. Dirty equipment — plant not cleaning properly (check water temperature, detergent, contact time). 2. Slow or inadequate cooling — milk not chilled fast enough; check the bulk tank and plate cooler. 3. Dirty cows / dirty milking — manure getting into the milk.
Butterfat % and Protein % — composition (and your pay) Many processors pay on components, not just volume. Low fat can signal sub-acute rumen acidosis (SARA) or a low-fibre ration; falling protein often points to an energy shortage in the diet. These track your feeding as much as your pay.
Freezing Point / Added Water — checks the milk hasn't been watered down (deliberately or by rinse water left in the line). A freezing point that drifts toward 0 °C suggests added water — usually a plant or process fault to fix.
Antibiotic / Inhibitory Substance test — pass/fail A failure means antibiotic residue got into the tank — a cow under treatment wasn't withheld. This can reject your whole load and your neighbours'. It's why treatment and withdrawal records (see "What health records should a dairy farmer keep?") are non-negotiable.
How to use the report Don't read one report — read the trend. A single high SCC could be one cow having a bad day; three collections climbing is a herd problem. Plot the numbers, set your own internal limits tighter than the penalty thresholds, and treat any line going the wrong way as a "find the cause" job, not a number to accept.
Sources AHDB Dairy — Understanding Your Milk Report. National Mastitis Council — Milk Quality Parameters. Teagasc — Milk Quality and Bactoscan Control.