Broiler deaths are not spread evenly over the batch. They come in patterns, and each week has its usual causes. If you know what to expect in each week and write deaths down every day, you will catch problems early, while they are still small and cheap to fix.
Why every bird counts
Mortality hits profit twice. You lose the chick you paid for and the feed it ate, and you lose the sale. A bird that dies near the end has eaten almost all its feed. For example, with 5,000 chicks, every extra 1% of deaths is 50 birds. At 2 kg each and an example rate of Rs 400 per kg, that is Rs 40,000 of sale gone, plus the feed. Mortality also pulls down your EPEF score, which you can check with the EPEF calculator.
Week 1: chick quality and brooding
The first week shows how good the chicks were and how good your brooding was. Research names yolk sac infection, often linked to hygiene at the breeder farm and hatchery, as a major cause of deaths in the first week.
Common causes:
- Weak chicks, poor navels, infected yolk
- Chicks too cold, or too hot, under the brooder
- Chicks that never found water or feed: dehydration and "starve-outs"
- Long, hot or cold transport from the hatchery
What helps:
- Check chicks on arrival and count dead ones in the boxes. Tell the hatchery the same day.
- Heat the shed and the litter before chicks arrive.
- Check crop fill: by 24 hours nearly all chicks should have a soft, full crop.
- Watch how chicks spread under the heat, day and night.
Weeks 2 and 3: immunity, litter and ventilation
Chicks now grow fast and the shed gets more crowded. Common problems:
- Gumboro (IBD), which often shows in this age range and weakens the bird's immune system. See Gumboro in broilers.
- Coccidiosis, which grows in wet litter around drinkers.
- Poor air in winter when curtains are closed tight, leading to ammonia and breathing problems.
- Vaccination mistakes: wrong timing, broken cold chain, uneven dose in water.
What helps: keep litter dry, raise drinkers as birds grow, give some fresh air even on cold nights, and follow the vaccination plan your vet gives you.
Weeks 4 to 6: heat, fast growth and disease
The last part of the batch carries the most weight and the most risk.
- Heat stress: heavy birds cannot lose heat well. In Pakistani summers a hot afternoon or a power cut can kill many birds in hours. See heat stress in broilers.
- Sudden death and ascites: research links both mainly to fast growth, with males more affected. Ascites is more common in cold weather and poor ventilation. Good ventilation and avoiding cold stress help.
- Respiratory and viral disease, such as Newcastle and H9 bird flu, which spread fast in a full shed.
- Leg problems and crowding, especially if density is too high.
What helps: plan for heat and load-shedding, keep density right for the season, do not keep birds longer than needed, and keep a tight farm gate.
A daily mortality log
Memory is not enough. Write deaths every day, at the same times, for each shed.
| Column | What to write |
|---|---|
| Date and bird age | e.g. 14 Jul, day 23 |
| Deaths morning | number found at morning round |
| Deaths evening | number found at evening round |
| Culls | weak, lame or small birds removed |
| Total so far | running total and % of chicks placed |
| Feed and water | bags used, water if you have a meter |
| Temperature | lowest and highest of the day |
| Notes | signs seen, vaccine given, power cut |
Count dead birds in front of a second person if you can, and remove them from the shed at once. In Poultry Curve's daily log you can enter deaths, feed and temperature per shed in a minute, and the running mortality percentage is shown for you.
When to worry
Small daily deaths are part of every batch. Call your vet the same day if you see:
- Deaths that double compared with the last two or three days
- Deaths that rise three days in a row
- A sudden drop in feed or water use
- Many birds dead in one part of the shed
- Signs like gasping, twisted necks, green or bloody droppings, swollen heads
Quick checks before the vet arrives
- Water: are all drinkers working, clean and at the right height?
- Feed: is it reaching every line? Is it wet or smelling bad?
- Temperature: is the shed too hot or too cold at bird level?
- Air: does the ammonia sting your eyes at bird height?
- Power: did a fan, pump or heater stop during the night?
Many sudden death spikes come from one of these, and they are the quickest to fix.
Safe disposal of dead birds
Do not throw dead birds in canals, fields or open pits, and do not sell them. Bury them deep with lime or burn them, far from the shed, as your vet or the local livestock office advises. Poor disposal spreads disease to your farm and your neighbours'.
Use the log to improve the next batch
At the end of the batch, look at deaths by week. If week 1 was high, talk to the hatchery and check brooding. If weeks 2 and 3 were high, look at litter, vaccination and ventilation. If the last weeks were high, look at heat, density and sale age. Writing the cause next to each spike makes the next batch better. Our guide on record keeping for poultry farms shows how to keep this simple.
The short version
Deaths follow a pattern: chicks and brooding in week 1, immunity and litter in weeks 2 and 3, heat and fast growth at the end. Write deaths every day, compare with your past batches, and call the vet early when the numbers jump.