Ration, repeat breeders and a culling decision in a crossbred herd
Balwinder Singh keeps 10 Holstein-Friesian crossbred cows, stall-fed. Average yield is 9 litres a day, ranging from 6 to 14 litres, and milk fat is 3.2%. Each cow gets 5 kg of a home concentrate mix (2 kg mustard cake, 2 kg wheat bran, 1 kg crushed maize), about 20 kg of berseem, and wheat straw free choice. No mineral mixture and no salt are given. Five cows have returned to heat after three inseminations, and two more were seen in heat only because a bullock cart passed the shed. Body condition score averages about 2.5 on a 5-point scale. Concentrate prices have risen sharply, and he proposes either to cut the green fodder and buy more concentrate, or to cull the five repeaters and buy a Murrah buffalo.
1. Assess the ration for a 9-litre average cow, showing your working, and recommend changes.
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Use a standard thumb rule, stating the assumption: maintenance roughly 1 kg concentrate per 100 kg body weight, plus 1 kg per 2.5 litres of milk. For a 400 kg cow giving 9 litres that is about 4 + 3.6 ≈ 7.5 kg. Even a more generous rule (2 kg maintenance + 1 kg per 3 litres) gives about 5 kg, which is exactly what he feeds – so he is at the very bottom of the range, with only 20 kg of green fodder, when a crossbred should get 25–30 kg.
So the answer is not 'cut the green fodder and buy more concentrate'. Green fodder is the cheapest source of energy, protein and fibre; cutting it would lower both yield and fat, and increase the concentrate bill. Wheat bran is bulky and low in energy, and the mix is short on minerals: he must add about 100 g mineral mixture and 50 g salt per cow per day. Keep the green fodder, balance the concentrate around a proper energy–protein mix, provide clean water, and re-check fat and yield after three weeks before blaming the cows' genetics.
2. Diagnose the repeat breeding problem and outline what should be done before any animal is culled.
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Five cows failing three services each is a herd problem, not five individual accidents. The clues point in several directions. Heat detection is poor – two cows were detected only incidentally, which is typical of silent heats in crossbreds, especially when the cows are thin and underfed. The ration supplies no mineral mixture, so phosphorus, copper, cobalt, selenium, zinc and manganese deficiencies are plausible contributors to delayed puberty, weak heats and early embryonic death. Body condition at 2.5 suggests a borderline energy status, and a high-yielding cow in negative energy balance will not conceive reliably.
Before culling: observe for heat twice daily for 20–30 minutes with a teaser or with tail-paint and record dates; inseminate at the correct time after onset of heat; correct the mineral and energy gap, deworm, and have the repeaters examined gynaecologically for uterine infection or ovarian dysfunction. Culling after three failed services is an economic decision, but only after heat detection, nutrition and genital health have been ruled out – otherwise the buffalo he buys may inherit the same problem.
3. He has two proposals: cut green fodder to buy concentrate, or cull the repeaters and buy a buffalo. Evaluate both as business decisions.
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Both proposals treat a symptom. Cutting the green fodder to afford concentrate trades the cheapest feed for the dearest one and is likely to reduce yield, lower fat and worsen fertility – a false saving that shows up as a bigger loss than the concentrate bill. Buying more concentrate without balancing the ration misses the mineral gap, so reproduction would still stall.
Buying a buffalo while five cows are subfertile adds a capital cost and a second enterprise on top of an unresolved problem. A buffalo may suit his resources in the long run, but the priority is to fix the present herd: correct ration, minerals, heat detection and a veterinary check. Culling should be decided animal by animal, after that, on the basis of response, age, milk yield and cost per litre produced, not because the animal failed three services. He should also compute cost per litre for the herd before and after the changes – that is the number that tells him whether any purchase is affordable.