One Hard Quarter, Four Litres of Milk and a Withdrawal Period
A smallholder in Kolhapur keeps four crossbred cows, two in milk. The best cow, yielding 12 L/day, dropped to 9 L in 10 days. Her left hind quarter is warm and hard, the foremilk shows flakes, and the strip-cup test is positive; the CMT on that quarter is grade 3 while the other quarters are negative. She is still eating well and has no fever. The farmer has been feeding 4 kg concentrate (cottonseed cake and rice bran), 15 kg sorghum fodder and no mineral mixture. A neighbour advises an oxytocin injection before each milking to 'let down' the milk, and continuing to sell all the milk because 'only one quarter is affected'. The village milk union collects twice daily and tests for antibiotics; the farmer needs the money and asks whether he can keep selling milk from the three healthy quarters while treating the affected one.
1. Diagnose the condition and list the actions for the next 48 hours, including what to tell the farmer about oxytocin and about selling milk.
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Diagnosis
Acute clinical mastitis of the left hind quarter, most likely bacterial (Staphylococcus aureus or a Streptococcus). The warm, hard quarter, flakes in the foremilk, positive strip cup and CMT grade 3 in one quarter with the others negative, in a cow still eating and without fever, point to a quarter-level infection rather than a systemic illness.
Next 48 hours
- Call the veterinarian. Take an aseptic milk sample for culture and sensitivity before the first dose, then start the prescribed intramammary preparation.
- Strip the affected quarter frequently (every 2–4 hours on the first day) into a separate container and dispose of it safely - not into the drain or the milk pool.
- Complete the full course; do not stop when the swelling subsides.
- Record cow, quarter, product, dose and date. The withdrawal period runs from the last treatment.
- No oxytocin. It is not a mastitis treatment, it masks the problem, and using it as a let-down shortcut on a cow under antibiotics is exactly how residues enter the village pool.
Can the three healthy quarters be sold?
No. The antibiotic circulates and is excreted in all four quarters, and the union tests the bulk tank, not individual quarters. One treated cow can fail the whole tanker and penalise the entire society. The milk must be withheld for the full withdrawal period stated on the product, and the farmer should be told this plainly, with the money loss acknowledged rather than hidden.
2. Quantify the cost of following the rule and decide whether to treat or cull the cow. Then explain what would happen if the farmer ignored the withdrawal period.
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Cost of doing it properly
- Milk withheld: about 4 days of treatment plus 4 days of withdrawal ≈ 8 days. At 9–10 L/day that is roughly 75–80 L; at ₹35/L, about ₹2,700–2,800.
- Treatment: vet visit, intramammary tubes, culture ≈ ₹1,000–1,500.
- Total loss ≈ ₹4,000.
Treat or cull?
Treat. A cow producing 9–12 L/day has no cull warrant: a replacement crossbred heifer costs ₹40,000–50,000 and takes about two years to calve and milk. Even if the quarter is lost permanently (about 25% of yield), the cow still pays for herself. Culling is considered only for a chronic, recurrent, treatment-unresponsive quarter, or a cow that is a persistent source of infection for the herd.
If the withdrawal period is ignored
- The union's antibiotic test fails the bulk milk. The whole tanker may be rejected and the society fined, and every member loses a collection - a loss many times the ₹2,800 the farmer was trying to save.
- Repeated residue failures can cost the society its buyer and its export licence.
- Residues in milk are a public-health issue, and the farmer's own family drinks from the same supply.
Also: do not dump antibiotic milk into soil or water; follow the veterinarian's or union's disposal advice.
3. Build a prevention plan covering milking routine, herd monitoring and the ration, and show how the ration gap contributed to the problem.
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Milking routine, every milking
- Wash hands; use a clean individual cloth or paper towel per cow; fore-strip into a strip cup to catch flakes early.
- Pre-dip, wipe dry, use full-hand milking (not finger-and-thumb), post-dip teats in 0.5% iodine.
- Keep cows standing for 30 minutes after milking so the teat canal closes before they lie down.
- Keep the shed floor dry and bedding clean; if machine milking, check liners, vacuum and pulsation.
Herd monitoring
- CMT all four quarters of every cow monthly and record the results; treat or segregate high-cell-count cows.
- Dry-cow therapy plus teat sealant at drying off, and a clean, dry calving pen.
The ration gap
4 kg concentrate, 15 kg sorghum fodder and no mineral mixture is short for 12 L. A crossbred cow at this yield needs roughly:
- 5–6 kg of a balanced concentrate (maize, soya or cottonseed cake, bran), with cottonseed cake capped so gossypol intake stays low;
- 25–30 kg green fodder and about 5 kg dry fodder;
- 50–100 g mineral mixture and 30–50 g salt per day;
- clean water available at all times.
A short energy and mineral supply lowers milk yield and depresses immune defence of the udder, so the cow was more vulnerable to infection. Correcting the mineral and energy gap often lifts yield by 1–2 L and improves resistance to the next infection.