Feed conversion ratio (FCR) in poultry

Feed conversion ratio (FCR) is the kilograms of feed consumed per kilogram of live-weight gain. It is the principal efficiency metric in broiler production, the most important non-price determinant of grow-out profitability, and a contractual benchmark in integrated broiler farming. Lower FCR means a leaner, more efficient bird.

Definition

FCR = feed consumed (kg) / live-weight gain (kg) over a defined period.

A flock that eats 3,400 kg of feed to grow 2,000 birds from 50 g to 2.0 kg of live weight (3,900 kg of gain) has an FCR of 3,400 / 3,900 = 0.87 — illustrative arithmetic but well below realistic ranges, since real production figures include feed wastage, mortality losses and water-fed feed losses.

Benchmarks for commercial broilers

Modern Cobb 500 and Ross 308 broilers in enclosed housing run between 1.4 and 1.9 at market age (35-42 days). An FCR below 1.6 is considered excellent and 1.6-1.9 is industry-standard. Recent commercial trials of Ross 308 at 35 days report mean FCRs of 1.371 in high-efficiency flocks and 1.527 in low-efficiency flocks; the gap is driven mostly by housing, brooding and disease management rather than genetics (Broiler Chicken).

Drivers of FCR

The leading levers are feed formulation (energy and amino-acid balance across starter, grower and finisher phases — see Starter Grower Finisher Feed), feed wastage, water-line hygiene, brooding temperature (Brooding Chicks), inter-batch sanitation (Biosecurity Cleaning Between Batches), housing type (Ec Poultry Shed vs Open Poultry Shed) and subclinical disease load. Heat stress raises FCR by depressing feed intake without proportionate growth.

Use in contract farming

Contract broiler agreements (Contract Broiler Farming) pay the grower a base per-kg rearing charge with an explicit FCR-and-mortality adjustment formula. Farmers beating the benchmark FCR earn an incentive; those running above the benchmark forfeit a portion of the rearing charge. A 0.05 improvement in FCR can swing batch payment by 10-15%. Self-mixing feed (Self Mixed Poultry Feed) is rarely used in contracts because FCR contracts depend on a known feed formula.

Limitations

FCR alone is a partial measure: it does not capture meat-yield-per-bird, breast-meat proportion or carcase quality. Modern integrators therefore combine FCR with mortality, average live weight and a composite production coefficient when evaluating flock performance.

References

Data Analytics of Broiler Growth Dynamics and FCR. PMC.
Cobb500 Broiler Performance and Nutrition Supplement. Cobb-Vantress.