Drying off or dehydrating? Eggshell membrane wrapped tightly around the chick
If a chick is not offered any feed and water and its body temperature is right, it will lose no more than 1-2 grams per day. If the chick’s temperature is too high, this can increase to 4-5 grams per day! Chicks that hatch too early have a high risk of dehydration. Drying off after hatching is a desirable process but drying out (dehydration) on the first day can lead to increased chick mortality on days 7 and 14, as well as poor broiler performance. Weight loss and chick temperature 10 8 6 4
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2 0
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Weight loss after 12 hours (%)
An eggshell membrane sticking tightly around the chick or a very dry membrane is a signal of overheating, eggshell damage, or shock and jolts during transfer (drying out). If transfer is automated, set the machine to a slower rate, and perform maintenance in time. If transfer is manual, draw attention to the need for careful handling.
41°C/106°F
40°C/104°F
Vent temperature
pr ot
Broiler weight loss after 12 hours, at two different body temperatures. Chicks with a high body temperature lose much more moisture.
Chick yield development after hatching
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optimal temperature
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65
Just hatched
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temperature too high
60
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Chick yield (%)
70
Time (hours)
Chick yield primarily tells you something about the process after hatching. The chick dries off and out, and this process reduces its bodyweight.
A dead dehydrated chick. The chick has lost too much moisture, because its body temperature was too high. This becomes visible with 10% moisture loss in the first 24 hours and is fatal when the moisture loss reaches 20%.
Different temperatures in the hatcher basket If you look at the temperature in the hatcher basket, you see that the dried chicks are already at the right temperature. Three chicks are clearly too cold. They are still wet (which can also be seen by the colour of their down), which causes them to cool down considerably.
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Ha tc he ry S i gnal s
