Understanding FCR
What feed conversion ratio measures, why a 0.05 change is worth more than most farmers think, and the six things that push it up.
FCRFeed conversion ratio — kilograms of feed to put on a kilogram of live weight. The single most useful number in broiler production, because feed is 60–75% of what the bird cost.Glossary → is the amount of feed it takes to put on a kilogram of live weight. Divide total feed consumed by total live weight sold and you have it. A flock that ate 65,000 kg of feed and sold 38,400 kg of chicken ran at 1.69.
It is the single most useful number in broiler production, for one reason: FeedونڈاwandaThe standard term. ‘Wanda rate’ is how feed prices are quoted.Glossary → is 60–75% of what the bird cost to raise. Nothing else on the cost sheet is close. Chicks are 10–15%, energy 5–8%, medicine and labour the remainder. If you improve one thing, improve this.
Why 0.05 matters more than it looks
A change of 0.05 in FCR sounds like nothing. On a 20,000-bird shed selling at 2 kg, it is about 2,000 kg of feed — roughly 40 bags a cycle, six cycles a year.
At current mill prices that is a meaningful sum for a change most farms could achieve by fixing feeder height alone. It does not appear on any invoice, which is exactly why it goes unnoticed: wasted feed is counted as consumption.
Benchmarks
FCR rises with age, because older birds convert less efficiently. So a ratio only means something next to the weight or age it was achieved at.
| Age | Weight | Cumulative FCR | | --- | --- | --- | | Day 21 | 950 g | 1.36 | | Day 28 | 1,550 g | 1.49 | | Day 35 | 2,200 g | 1.60 | | Day 42 | 2,900 g | 1.71 |
These are typical targets for modern commercial strains under good management. Pakistani field results commonly run 0.10–0.20 behind them, and a farm holding 1.65 at 2 kg is doing well.
Quoting “our FCR is 1.55” without saying at what weight is meaningless. At 1.4 kg it is poor; at 2.2 kg it is excellent.
What pushes FCR up
Feed wastage at the pan. The most common and the most fixable. Pans set too low, or filled too full, spill feed into the litter where the bird never eats it — but you still bought it. Feeder lip at back height, and never more than one-third full.
Water. Birds eat in proportion to what they drink. Blocked nipples, low line pressure or high-TDS water cuts intake efficiency before it shows up anywhere else. Check flow rate at the far end of the line, not at the tank.
Subclinical coccidiosis. Damages the gut lining without producing visible sick birds. This is the usual explanation when FCR drifts upward but mortality looks completely normal.
Heat stress. Above roughly 30°C birds eat less and convert what they eat less efficiently. It is why summer cycles almost always run worse than winter ones, and why summer stocking ceilings are lower.
Stocking densityHow much live weight a shed can carry, measured in kg per square metre — not in bird count. Summer ceilings are lower because heat load binds before floor space does.Glossary →. Crowding in the final week raises FCR and Mortality · deathsامواتamwaatThe daily number every farmer tracks, even on paper.Glossary → together. A shed holds a weight of chicken, not a number of birds.
Mycotoxins. They reduce nutrient absorption. Suspect them when a change of feed lot lines up with a step change in performance that nothing else explains.
Measuring it honestly
Two things make an FCR figure wrong more often than anything else:
- Not counting the feed left in the shed. Weigh the remainder and subtract it. An uncounted half-tonne flatters the ratio by about 0.01 per 400 kg on a typical flock.
- Using bird count rather than weighed sale weight. Sample at least 100 birds across the shed, not just the ones nearest the door — those are consistently heavier.