How to Calculate Mortality Rate in Poultry
Understanding mortality rate is crucial for any poultry farmer, whether you are managing broilers, layers, or free-range chickens. It serves as a key performance indicator (KPI) for the health of your flock and the efficiency of your farm management practices. High mortality rates not only indicate disease or management issues but also directly impact your profit margins.
The Poultry Mortality Formula
The calculation for poultry mortality is straightforward. It represents the percentage of birds that have died compared to the total number of birds placed at the beginning of the cycle.
Mortality Rate (%) = (Total Number of Dead Birds ÷ Initial Flock Size) × 100
Conversely, Livability is the percentage of birds that survived the period.
Livability (%) = 100 – Mortality Rate (%)
Practical Example
Let's say a farmer starts a broiler cycle with 5,000 day-old chicks. Over the course of the 45-day cycle, the farmer records a total of 200 deaths.
- Initial Flock: 5,000
- Deaths: 200
- Calculation: (200 ÷ 5,000) × 100 = 0.04 × 100 = 4%
In this scenario, the mortality rate is 4%, meaning the livability rate is 96%. This is generally considered an acceptable figure in commercial broiler farming.
Why Calculate Mortality Rate?
Tracking this metric allows poultry managers to:
- Detect Disease Outbreaks Early: A sudden spike in daily mortality is often the first sign of viral or bacterial infections (e.g., Newcastle disease, Coccidiosis).
- Evaluate Management Efficiency: High mortality can result from poor ventilation, overcrowding, temperature stress, or contaminated feed.
- Forecast Financials: Knowing how many birds you have left allows you to accurately predict feed consumption for the remainder of the cycle and the final revenue from meat or eggs.
Standard Benchmarks
What is considered a "good" mortality rate varies by bird type and region, but general industry standards are:
- Broilers: Less than 3% to 5% over a 6-week cycle is excellent. Above 6% requires investigation.
- Layers (Rearing Phase): Generally less than 3-4% up to 18 weeks.
- Layers (Laying Phase): Approximately 0.5% to 1% per month.
Tips to Reduce Poultry Mortality
If your calculator results show a "Poor" or "Warning" status, consider checking the following:
- Biosecurity: Restrict visitors and ensure strict sanitation to prevent pathogens entering the shed.
- Brooding Temperature: Ensure chicks are kept at the correct temperature (usually 32-34°C for day-old chicks) to prevent piling and suffocation.
- Water Quality: Regularly flush water lines and check for biofilm or bacterial contamination.
- Feed Management: Ensure feed is free from mycotoxins and appropriate for the age of the bird.
Frequently Asked Questions
How do I calculate Daily Mortality Rate?
Daily mortality is calculated by dividing the number of birds found dead on that specific day by the number of birds alive at the start of that day, multiplied by 100.
Does this calculator account for culled birds?
In strict biological terms, culled birds (removed due to sickness or deformity) are often counted towards mortality figures because they represent a loss of saleable product. You should include culled birds in the "Total Number of Deaths" input for an accurate financial picture.