What is a good EPEF score in commercial poultry?

Poultry • productionVerified Formula

European Production Efficiency Factor (EPEF / EPEI) Calculator

Computes the standard international benchmark metric combining flock livability, market weight, cycle length, and FCR into a single index score.

Parameters

Calculated Output

European Production Efficiency Factor

428.8EPEF69.2 g/day Avg Daily Gain

What This Result Means

Your calculated EPEF is 428.8 (Excellent Performance (>400)). Daily gain averaged 69.2 grams/day over 38 growout days.

Calculation Details & Equivalents

EPEF / EPEI Index Score

428.8

Average Daily Gain (ADG)

69.2 g/bird/day

Livability Rate

96%

Mortality Rate

Veterinary & Animal Science Advisory

This calculator provides evidence-based estimates derived from published veterinary equations (NRC, WSAVA, FAO). Outputs are intended for educational and decision-support guidance only. Always consult a licensed veterinarian or qualified specialist for clinical diagnosis, treatment planning, or prescription drug administration.

Understanding the European Production Efficiency Factor (EPEF / EPEI) Calculator

What This Calculator Does

This European Production Efficiency Factor (EPEF / EPEI) calculator computes the standard global benchmarking metric for commercial broiler chicken production. It integrates flock livability, final market weight, harvest age in days, and Feed Conversion Ratio into a single composite score.

How to Use This Calculator

Enter your flock's livability percentage (100% minus mortality), average bird slaughter weight, age at harvest (days), and overall Feed Conversion Ratio (FCR). The tool computes the EPEF index score and average daily gain (ADG in grams/day) to benchmark against industry standards.

Key Factors That Affect the Result

World-class benchmarks: In modern poultry operations, an EPEF score of 400+ denotes superior management, while scores from 350 to 399 reflect solid commercial performance.
Balanced multi-variable metric: Unlike raw weight or FCR alone, EPEF rewards high growth velocity and low flock mortality simultaneously.
Age sensitivity: Faster growth (higher weight at fewer days) significantly lifts the EPEF score because the denominator represents bird maintenance days.
Metric standardization: The formula requires average bird weight in kilograms, which our tool automatically handles regardless of whether you input in pounds or kilograms.

Why This Matters for Your Poultry

EPEF allows poultry farmers, production managers, and integrators to fairly compare performance across different housing types, seasons, genetic lines, and feed formulations across global standards.

Veterinary Advisory: This calculator provides production efficiency calculations based on international FAO and breeding company standards. Consult an avian veterinarian or poultry nutritionist to investigate flocks scoring below expected production targets.

Reviewed & verified by Dr. Imad Khan, DVM, MSc · Doctor of Veterinary Medicine & Masters in Poultry Science · View editorial credentials →

Formula & Mathematical Methodology

Standard Mathematical Formula

EPEF = [Livability (%) × Average Live Weight (kg) × 100] ÷ [Age (days) × FCR]

Formula Variables Defined

LivabilityLivability Percentage(%)

Percentage of birds surviving to harvest (100% - Mortality %)

WeightAverage Live Weight(kg (or lbs))

Average weight per bird at slaughter

AgeSlaughter Age(days)

Total growout duration in days

FCRFeed Conversion Ratio

Feed consumed divided by live weight gain

Step-by-Step Calculation Example

Example: High Performance Broiler Flock

96% livability, 2.60 kg (5.73 lbs) average weight, 38 days harvest age, 1.55 FCR.

Weight in kg = 5.73 lbs ÷ 2.20462 = 2.60 kg
Numerator = 96 × 2.60 × 100 = 24,960
Denominator = 38 × 1.55 = 58.9
EPEF = 24,960 ÷ 58.9 = 423.8

Final Output: 423.8 EPEF Score

Key Assumptions

Average weight is converted to kilograms internally per standard international EPEF convention.

Biological Limitations

Verified Scientific & Veterinary Sources

Version: 1.0•Methodology Reviewed: 2026-01-20

1. Ross 308 Broiler Performance Objectives & Nutrition Specificationsindustry-standard

Aviagen Technical Services (2022). Aviagen Broiler Management Guide

Access Source Authority

2. Poultry Development Review: Production Performance Standards & Efficiency Metricsgovernment

Food and Agriculture Organization (FAO) of the United Nations (2018). FAO Animal Production and Health Guidelines

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European Production Efficiency Factor (EPEF / EPEI) Calculator — FAQs

Scores over 400 represent world-class performance. Scores from 350 to 399 are solid commercial results, while scores under 300 indicate opportunities for flock improvement.