How warm should the brooder be this week?

The two schedules disagree by two weeks about when the heat comes off, and neither is averaged into the other. The Philippine column covers weeks 1 to 4 only, because that is all the one Philippine study covers.

Column by column: the MSD Veterinary Manual starts day-old sisiw at 29.4 to 32.2°C and drops 2.8°C a week to 21.1°C; Mississippi State Extension reaches the same 21.1°C by the end of week three, two whole weeks earlier; the Philippine column is the 31°C plus or minus 1°C textbook band from A. L. Lambio's Poultry Production in the Tropics (UPLB, 2010), as quoted by the 2025 Pampanga State Agricultural University trial, and it covers the first four weeks only.

What to do at your room temperature

Kunin mo ang temperatura sa loob mismo ng brooder, at chick level. Find the row closest to what you read, then go across to the week the batch is in. Notice how much of this table says the room is already too warm.

Key▲add heat✓inside the band▼too warm

Read the temperature at chick level inside the brooder, not off a weather app. The app gives you the outdoor air, which is a different number and usually a cooler one.

How big the brooder has to be

Floor space is Penn State Extension's small-flock figure, converted from square feet. A tray of 50 sisiw needs about 1.2 m² in week one and about 4.6 m² by week six, so size the kahon for the last week rather than the first.

Chick counts are what a hatchery actually sells a backyard keeper: a tray, a box, or a handful from a neighbour who hatched more sisiw than she needed.

Watch the sisiw, not the thermometer

Every source above falls back to behaviour, and so should you. Ang mga sisiw ang pinakamalinaw na thermometer sa kulungan, kasi sila ang nakatayo doon. The four states below are quoted fromAviagen's Ross Broiler Management Handbook 2025, Figure 2.10.

No wattage appears anywhere on this page, and not because nobody has ever printed one. Mississippi State Extension sizes a 60-watt incandescent bulb to a cardboard box holding up to 25 chicks. That is a bulb matched to one enclosure, not a rate you multiply by your own flock, and no veterinary manual, breed company or standard publishes the scalable version, because the answer moves with the box and the air around it. The figures circulating online are retailer rules of thumb. The behaviour table above is what the sources themselves fall back on.

Why the schedules disagree, and why neither was averaged

The real question in a Philippine brooder is not how to add heat. Ang tanong ay kung kailan papatayin ang heater. PAGASA puts the mean annual temperature here at 26.6°C and the warmest month at 28.3°C, which already sits at or above the week-three target in both of the schedules above. From week three onward, at anything from 28°C up, both of them want the heat off entirely. Sa tag-araw, a week-one brooder in a closed kahon can sit above the 32.2°C ceiling on ambient alone, walang heater na nakabukas.

The two imported schedules are two weeks apart on when that happens, and hindi sila pinagsama dito. Averaging two sources that disagree invents a third one nobody published, and the gap between them is information: it tells you the answer is a band, hindi isang eksaktong digit.

The Philippine figure for native na sisiw is not a third measurement either. The PSAU trial prints 31°C plus or minus 1°C as the requirement it brooded inside, footnoted to Lambio's UPLB text. What that trial measured was its own nine treatment means, 30.42 to 32.58°C. So the Philippine column is a textbook band, not a national standard and not an outcome anybody weighed, kaya blangko ang hanay mula linggo 5.