Chick yield
Assessment of chick yield Investigate cause 69
X X X
68 67
Repeat Ideal
X X X X X
66 65
X 1
2
Repeat Investigate cause
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Flock number Flock 1: Good chick yield. Flock 2: High chick yield, but still acceptable. Flock 3: Low chick yield.
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Chick yield is only an indication. If it is too high or low, monitor it closely. If the result is extreme, look for the cause.
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Causes of deviating chick yield Low chick yield
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1. Chicks spent too long in the hatcher.
High chick yield 1. Chicks did not spend enough time in the hatcher (maybe they hatched later than planned).
2. Low incubation temperature 2. High incubation temperature (chicks hatch later, and therefore (chicks hatch earlier, and therefore spend longer in the hatcher). spend less time in the hatcher). 3. Low RH in the incubator (chicks are already dehydrated when they hatch).
3. High RH in the incubator.
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rig
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< 66%: low chick yield A batch of chicks with a low chick yield has been held too long in the hatcher. Perhaps they hatched earlier than expected, because the temperature was too high.
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Chick yield (%)
Chick yield is the weight of day-old-chicks, expressed as a percentage of initial egg weight at the start of the incubation process. It is not a good indicator of chick quality but does tell you something about the time elapsed after hatching (drying up = weight loss). So, the timing of weighing is very important, because once the chicks have hatched, they start drying up and therefore lose weight. If you wait for a couple of hours, you get a completely different picture. Make sure you always weigh at the same time, so the results can be compared. Ideally, use exactly the same eggs as the eggs the chicks hatched from. Calculating chick yield based on the average egg weight in a setter tray and the weight of the hatched chicks gives a far too general average, and gives little information about hatchability. Proper insight into the variation can give you valuable management tools to improve egg quality or the incubation process. Yet, this is still the most practical and commonly used method.
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> 68%: high chick yield A batch of chicks with a high chick yield has hatched very recently, or incubated at a too low temperature. This could be caused by factors such as lower heat production by the embryos, use of smaller hatching eggs or eggs stored too long, or other non-optimal conditions.
Chick yield is calculated as the total chick weight expressed as a percentage of the initial egg weight at the start of the process.
10. C h i c k q u a l i t y
Do not forget to deduct the weight of the setter tray to obtain the actual egg weight. When weighing the chicks, deduct the weight of the hatcher basket to obtain the actual chick weight. This is obvious, but is overlooked sometimes.
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