What Is Mastitis?
Mastitis is inflammation of the udder caused by bacterial infection. It is the number one economic disease in dairy farming worldwide.
| Type | Signs | SCC Level | Treatment |
|---|---|---|---|
| Acute Clinical | Hot, swollen quarter; flakes/clots in milk; cow off-feed, fever | >1,000,000 | Immediate IMM antibiotic + NSAID, systemic if fever >40°C |
| Subacute Clinical | Abnormal milk; mild swelling; cow eating normally | 500,000–1,000,000 | IMM antibiotic course (3–5 infusions) |
| Chronic Clinical | Recurrent flares; fibrosis; reduced quarter yield | Variable — often high | Treat or cull — 3+ cases/lactation = cull |
| Subclinical | No visible signs; elevated SCC only | 200,000–1,000,000 | Dry-cow therapy; monitor; manage milking hygiene |
The Five-Point Mastitis Control Plan
Internationally proven. Every dairy herd should implement all five points — not just one or two.
Post-Milking Teat Dipping
Dip all 4 teats in 0.5% iodine post-dip within 30 seconds of unit removal. Kills bacteria before teat canal closes. Non-negotiable — this single step reduces new infection rate by 50%.
Dry-Cow Therapy
Infuse all 4 quarters with long-acting IMM antibiotic at dry-off. Add teat sealant for cows in high-risk housing. Eliminates existing subclinical infections and protects through the dry period.
Cull Chronic Cases
Cows with 3+ clinical cases per lactation or SCC persistently above 1M are profit destroyers. They infect pen mates. Calculate the cost — culling almost always wins economically.
Maintain Milking Equipment
Check vacuum (40–44 kPa) and pulsation (55–65 cycles/min) monthly. Replace liners every 2,500 milkings or 3 months. Faulty equipment is a top 3 cause of mastitis on commercial farms.
Treat Clinical Cases Promptly
Identify cases at morning milking by stripping foremilk. Start IMM antibiotic same day. Delayed treatment → chronic infection → quartered cow. Record drug, dose, and withdrawal in HerdManager.co.
Teat Dipping Protocol
The right product, right concentration, right technique. Most farms do it wrong.
Pre-Dip (Before Milking)
0.1% iodine or 0.5% chlorhexidine. Apply, leave 30 seconds minimum, wipe completely dry with individual paper towel per cow. Pre-dip targets environmental mastitis (E. coli, Klebsiella).
Post-Dip (After Milking)
0.5% iodine post-dip. Cover entire teat — top two-thirds minimum. Do NOT wipe off. Apply within 30 seconds of unit removal while teat canal is still open. Critical for contagious mastitis prevention.
Dip Concentration
Iodine teat dips: 0.1% pre-dip, 0.5% post-dip. Do not over-dilute (reduces efficacy). Do not under-dilute (causes teat-end damage and irritation). Use a calibrated dispenser.
Spray vs Dip
Dipping (cup applicator) gives better coverage than spraying. If using a spray, use pressure sprayer at 10–15 cm distance, cover all surfaces. Single dip cups are most hygienic — change after each use.
SCC Monitoring
Somatic Cell Count is your early warning system. Track it monthly — act before clinical signs appear.
| SCC Range (cells/mL) | Status | Milk Loss | Action Required |
|---|---|---|---|
| < 100,000 | Excellent | None | Maintain current protocol |
| 100,000 – 200,000 | Good | Minimal | Monitor monthly |
| 200,000 – 400,000 | Warning | 2–7% | CMT test, review hygiene, check milking equipment |
| 400,000 – 1,000,000 | Action | 7–16% | Treat subclinical infection, review DCT compliance |
| > 1,000,000 | Chronic / Cull | >16% | Consider culling — infection risk to herd |
California Mastitis Test (CMT) — Field Use
CMT is the cheapest mastitis diagnostic available. Strip 1–2 mL foremilk from each quarter into the paddle. Add equal volume CMT reagent. Rotate for 10 seconds. No gel = negative. Slight gel = trace. Distinct gel = ++ (subclinical). Strong gel = +++ (clinical/chronic). Use monthly on all cows above 200,000 SCC.
Dry-Cow Therapy
The dry period is your best window to cure existing infections and protect through calving. DCT is the highest-ROI mastitis intervention.
When to Administer
At dry-off (last milking). Infuse all 4 quarters regardless of SCC status (blanket DCT) for high-risk housing. Selective DCT (SCC <200K, no clinical history) is appropriate for well-managed low-risk herds.
Dry-Cow Products
Long-acting dry-cow tubes based on cloxacillin benzathine, cefalonium or cefquinome are widely used, and amoxicillin/cloxacillin combinations are also sold. Each product sets its own rules — usually a minimum time between treatment and calving plus a milk-withholding time after calving — so follow the product label and your vet exactly.
Teat Sealant
Internal teat sealants (bismuth subnitrate paste — e.g., Teatseal, Orbeseal) physically block the teat canal. They contain no antibiotic, so most labels set no milk withdrawal — strip the plug out at the first milkings after calving. Use after DCT infusion, or alone in very low-SCC cows. Highly effective in loose-housed herds.
Milk Withholding After Calving
Milk from DCT-treated cows must be kept out of the tank after calving until the withdrawal time on the product label has passed. Record the infusion date and product in HerdManager.co so the treatment is on the cow's record when she calves.
Treatment of Clinical Mastitis
Act fast. Every 12-hour delay increases the risk of permanent quarter damage.
| Drug | Route | Milk Withdrawal | Best For |
|---|---|---|---|
| Cefquinome (IMM) | Intramammary | Per product label | Most clinical mastitis |
| Cefapirin (IMM) | Intramammary | Per product label | Mild/moderate clinical |
| Amoxicillin (IMM) | Intramammary | Per product label | Strep/gram-positive |
| Oxytetracycline (systemic) | IM injection | Per product label | Systemic + IMM combo |
| Penicillin G (systemic) | IM injection | Per product label | Streptococcal mastitis |
| NSAIDs (Flunixin/Meloxicam) | IV/IM | Per product label | Pain relief, reduce inflammation — always add for acute cases |
Milk withdrawal: always follow the product label
Withdrawal times belong to each product, not just the drug name: two brands of the same antibiotic can carry different milk withdrawal times, and approved products and times differ between countries. Discard milk for the full time on the label of the product you used — or your vet's written instruction for any off-label use — and record the treatment in HerdManager.co so the Milk Withdrawal Active alert runs until the safe date. Our free Withdrawal Clock works out the exact safe time.
Chloramphenicol is banned in food-producing animals
Never use chloramphenicol, nitrofurans, or nitroimidazoles in dairy animals. Their use in food-producing animals is prohibited in the US, UK, Canada and EU, and residues lead to milk rejection and legal penalties. Always consult a licensed veterinarian for treatment protocols.
Track Mastitis with HerdManager.co
Every mastitis case, treatment and withdrawal period — logged and followed up.
Health Event Log
Record every mastitis case as a health event with its severity, symptoms, vet and notes, and add each treatment to the case's treatment log. The full health history stays on the cow's record.
Milk Withdrawal Alerts
Set a withdrawal period on each medicine; when it is given, the app shows a daily Milk Withdrawal Active alert until the safe date.
Mastitis Status with Milk Records
Log a mastitis status — none, subclinical or clinical — with each cow's milk record, so infected cows sit right next to their yield.
Mastitis Alerts
A mastitis-suspicion alert appears on the dashboard when a milk record is marked subclinical or clinical. Schedule herd CMT tests as farm events and get in-app reminders before they are due.
Cull-or-Keep Decisions
Every case and treatment stays on the cow's record, so repeat cases are easy to spot. Our free Cull-or-Keep calculator compares the cost of keeping a cow with replacing her.
Record in the Shed
HerdManager.co works in any phone browser and can be added to your home screen, so cases and treatments are logged at the cow side. It needs an internet connection.
Milking Hygiene & Equipment
Good milking routine is the foundation. Equipment failure is a silent mastitis cause on many farms.
Milking Routine (every milking)
1. Strip 3–4 squirts foremilk (check for abnormalities). 2. Pre-dip — 30-second contact. 3. Wipe dry with individual paper towel. 4. Attach unit. 5. Milk out fully. 6. Post-dip immediately on removal.
Equipment Maintenance
Check vacuum gauge monthly (40–44 kPa). Check pulsation (55–65 cycles/min). Replace rubber liners every 2,500 milkings or 3 months. Backflush clusters between cows. Sanitize milking line daily with caustic then acid wash.
Housing Cleanliness
Scrape manure twice daily minimum. Keep lying area dry (wet bedding = massive environmental mastitis pressure). Lime alleys and lying areas weekly. Adequate space per cow (5–6 m² loose housing).
Staff Training
Milking staff must follow routine consistently — every milking, every cow. Train new staff before they touch animals. A single untrained relief milker can spike farm SCC in 2 weeks.
Fresh Cow Management
Check all fresh cows (0–14 DIM) at every milking. Strip foremilk, check udder temperature and firmness. Transition stress = high mastitis susceptibility. CMT all fresh cows at Day 3 and Day 10.
Water Quality
Contaminated water in the milking machine wash cycle transfers bacteria to teat surfaces. Test water source annually for coliform counts. Use chlorinated water for equipment washing.
Frequently Asked Questions
Common mastitis questions from dairy farmers.
Stop Losing Money to Mastitis
Log mastitis status, record treatments and get milk-withdrawal alerts with HerdManager.co.
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