Repeat breeders, a mastitic quarter and a feed bill in a 20-animal dairy
Sunita Bai of Silwani, Raisen, keeps 14 crossbred cows and 6 Murrah buffaloes. Three cows calved 140 to 160 days ago and have been inseminated four times each at observed heats, but have not conceived; heats are weak and short. The cows are in body condition score 2.25 on a 5-point scale and have no vaginal discharge. The daily ration is 20 kg green maize and 3 kg of a wheat bran and mustard cake mix, with no mineral mixture. One cow has clots in the right fore quarter, the CMT gives a score of 3, and she yields 8 litres. The village milk union deducts Rs 2 per litre when the bulk tank somatic cell count crosses 500,000 cells per mL. The 500-litre bulk milk cooler is 60 per cent full each morning. Two buffaloes have not shown heat for over 100 days. The AI technician wants to repeat the same frozen semen.
1. How would you sort out the infertility problem, and should the three cows be inseminated again on the next heat?
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Separate the two problems.
- The three cows cycling at roughly 21-day intervals but not conceiving are repeat breeders with a strong suboestrus component - weak, short heats - not true anestrus. A BCS of 2.25 on a ration of 20 kg maize plus 3 kg cake, with no mineral mixture, points to negative energy balance, which suppresses oestrus and raises early embryonic death.
- The two buffaloes silent for over 100 days are a separate anestrus problem, largely nutritional and seasonal, plus the possibility of silent ovulations.
Work-up before any more semen is used
- Breeding and heat register: dates, intervals, service number, technician.
- Body condition scoring and a ration check for energy, protein, phosphorus and trace minerals.
- A white-side test or endometrial cytology, because after four services subclinical endometritis is a real possibility; ovarian palpation or ultrasound to confirm cyclicity.
- Semen handling: thaw temperature, time from thaw to deposition, site of deposition, and the bull used.
- Rule out brucellosis in the herd before concluding it is purely management.
Do not inseminate them blindly again on the next weak heat. Skip one cycle, correct energy through extra concentrate and 50-100 g mineral mixture per day, observe heats twice daily for 20 minutes with a teaser, and breed on a clear standing heat, changing the bull or the semen batch.
2. What must be done about the cow with clots and a CMT score of 3 - treatment and, above all, the milk?
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Stop pooling her milk today. Clots plus CMT 3 is clinical mastitis, and her milk will drive the bulk tank somatic cell count over the limit and trigger the Rs 2 per litre deduction on the whole tank.
Action at milking
- Strip each quarter into a strip cup at every milking; milk the affected quarter last; disinfect hands and teat dip; keep her bedding dry.
- Culture if a laboratory is reachable; otherwise treat on veterinary advice with an intramammary preparation effective against Staphylococcus aureus and environmental streptococci, plus frequent milking out of the quarter.
Withholding
- Withhold all four quarters for the label withdrawal period (commonly 72-96 hours for intramammary products, longer for systemic) plus a 2-3 day safety margin, and mark her in the register so nobody adds her milk to the cooler.
- Residue-positive milk is a food-safety violation, not just a commercial loss.
Return to the pool
- Only after the withdrawal period, when the quarter looks normal and CMT falls to 1 or below. Retest before pooling.
Longer view
- A cow with repeated flare-ups and persistently high SCC is a culling decision to be taken at drying off, not mid-lactation, and only after the economics of replacement are worked out.
3. Calculate the concentrate needed for a 450 kg cow giving 12 litres, and decide whether buying more concentrate is the best use of money at Rs 24 per kg concentrate and Rs 38 per litre milk.
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Requirement
- Maintenance allowance on a good roughage base: about 1.5 kg concentrate.
- Production allowance: 1 kg per 2.5 litres = 12 / 2.5 = 4.8 kg.
- Total: about 6.3 kg per day. She is getting 3 kg, a shortfall of about 3.3 kg.
Does it pay on milk alone?
- Extra cost: 3.3 x Rs 24 = Rs 79 per day.
- If it buys 1.5 litres at Rs 38, the return is Rs 57. On milk alone it does not pay, so the answer is not simply to pour in concentrate.
Where the money actually comes back
- Lifting BCS from 2.25 to about 3.0 shortens the service period and the calving interval; one calf plus one extra lactation is worth far more than Rs 22 a day, so the return is reproductive, not immediate milk.
- Cheaper route: replace part of the wheat bran with 5-6 kg legume fodder (berseem or lucerne), use a home-mixed maize plus cake concentrate instead of purchased feed, and add 50-100 g mineral mixture.
Decision Increase concentrate and legume fodder for the three repeat breeders and the thin cows only, not for the whole herd, and re-check BCS after six weeks. That targets the money where the loss is actually occurring.