- ✓Set target weights by age suited to your breed and your poultry house
- ✓Monitor laying: percentage, normal curve, alerts
- ✓Understand the role of the weight at 18 weeks and of light in the layer
Target weights for broilers
The level 2 benchmarks become your targets: you start from the results of your last two or three flocks, you aim for 5% better, and you write the target for each week on the record sheet before the chicks arrive. Each weighing is then read as a gap from the target: “week 3: 880 g for a target of 920, −4%”. The gap triggers the search for a cause (feed, heat, water, health), not the weighing itself.
| Week | White broiler (cautious target) | Coloured chicken (indicative) |
|---|---|---|
| 1 | 160 g | 90 g |
| 2 | 430 g | 220 g |
| 3 | 900 g | 400 g |
| 4 | 1,450 g | 620 g |
| 5 | 2,000 g | 870 g |
| 6 | 2,450 g | 1,150 g |
| 8 | — | 1,650 g |
| 12 | — | 2,300 g |
Coloured chickens vary a great deal according to the breed and the feed: build your own table from your weighings, then stick to it.
The laying curve
Daily laying rate (%) = eggs collected ÷ hens present × 100. It is calculated every day, noted, and plotted week by week. A normal curve for a well-reared brown layer:
| Age | Expected laying rate | Remark |
|---|---|---|
| 18 to 20 weeks | First eggs (small) | Switch to layer feed |
| 21 to 22 weeks | 50% | Rapid rise: 5 to 10 points per week |
| 26 to 30 weeks | Peak, 90 to 95% | Lasts 8 to 12 weeks if all goes well |
| After the peak | Slow decline, about 0.5 of a point per week | An egg that keeps getting bigger |
| 72 to 80 weeks | 60 to 65% | Culling |
Over a year of laying, a good layer gives around 300 eggs. The alerts: a drop of more than 5 points in one week (disease, heat, water, feed, light, fright), a peak below 85% (pullets too light at 18 weeks, layer feed given too late, insufficient light), abnormal eggs (soft shells, misshapen, watery white: disease or calcium).
The weight at 18 weeks and light
The laying peak is decided before the first egg. A pullet that reaches 18 weeks at the target weight for her breed (often around 1.5 kg for a brown layer; check your pullet supplier's table or ask NEXTEKCI for it), with good uniformity, will give a high, long peak. A pullet that is too light lays late, lays little, and lays small eggs; too heavy, she has laying and liver problems.
Light is the second steering lever: no stimulation before 17 to 18 weeks, then you increase by half an hour to one hour per week up to 16 hours of light per day, and you never reduce the light of a layer in lay. A power cut that shortens the days makes laying drop. The details of the programme are at level 5.
Reading the gap and acting
- Weight gap across the whole flock: the target may be too ambitious for the house; check density, water and heat first.
- Gap that appears in one week: an event (feed, heat, disease); record sheet.
- Laying that rises slowly: weight at 18 weeks, feed, light.
- Laying that drops: water and heat first, then feed (change, calcium), light, fright (dog, visitors, noise), disease (level 3).
For the entrepreneur
- ›Write the flock's targets before the chicks arrive; judge the weighings by the gap from the target.
- ›For layers, two figures to ask for: the weight at 18 weeks and the week's laying rate.
- ›Protect the layers' light: generator or back-up lamps; never a shortened day.
For the technician
- ›Weighings compared with the target, gap calculated in %, cause sought for any gap of more than 5%.
- ›Eggs counted every day, laying rate calculated, curve plotted every week.
- ›Pullets weighed every week up to 18 weeks; lighting programme followed to the minute.
The 3 questions to ask your technician this week
- What is the weight gap from the target this week, and what cause have you found?
- What is this week’s laying rate compared with last week?
- How many hours of light do the layers receive, and what happens in the event of a power cut?
Key points
- •Targets written before the flock; each weighing is read as a gap from the target.
- •Cautious white broiler: 160 g (wk 1), 430 (wk 2), 900 (wk 3), 1,450 (wk 4), 2,000 (wk 5); coloured chickens: your own table.
- •Laying rate = eggs ÷ hens × 100; 50% around 21-22 weeks, peak 90-95% around 26-30, −0.5 of a point per week thereafter, culling at 72-80 weeks, ≈ 300 eggs per year.
- •Alerts: drop > 5 points in one week, peak < 85%, abnormal eggs.
- •The peak is decided by the weight at 18 weeks and by light (up to 16 h, never reduced).