15
AF36 US Issue 03
6 HUMIDITY AND VENTILATION
UNDERSTANDING HUMIDITY
Short term va riations in humidity a re not i mportant.
The a verage humidity over the i ncubation period
needs to be near optimum to achieve the ideal
wei ght l oss.
Hi gh humidity for the day or two of hatching is also
i mportant. Beware chronic, excessive humidity.
Typical Humidity:
Generally a ccepted incubation RH l evels for s pecies groups
i n Ova ti on 28 i ncubators:
During incubation: Poultry
50-60% RH
Waterfowl
55-65% RH
Parrots
40-50% RH
Hatching:
All species
60-65% RH
Typical Weight Loss:
Typi ca l ideal weight l osses for species groups:
Poultry
13%
Waterfowl
14%
Parrots
16%
For more specific information on particular species’ requirements check the relevant literature.
Two fa ctors affect incubation humidity: water evaporation within the cabinet (from eggs as well as from additional water) and
l evels of ventilation. The water content of the air being drawn through the incubator will also have an effect.
There a re two methods available to bird breeders to a chieve correct humidity l evels:
1
:
Monitor humidity levels and adjust to match published guidelines for different species.
2
: Monitor egg weight loss which varies as a direct result of humidity and correct against published weight loss figures
for the species. This is the most reliable method and is recommended
–
particularly where poor hatch rates are
experienced or if eggs of high value are being incubated.
Eggs lose moisture through their shells and the rate of evaporation depends on the humidity levels around the eggs and
the shell porosity. During incubation eggs need to lose a fixed amount of water which corresponds to a loss in weight
of around 13-16% depending on species. By weighing eggs periodically during incubation it is possible to monitor and,
if necessary, correct humidity levels to achieve the correct weight loss.
For more detailed i nformation on all aspects of egg incubation i ncluding helpful a dvice on getting best results please visit our
website a t www.brinsea.com/brochures/BrinseaIncubationHandbook2016.pdf
Summary of Contents for Ovation 28 Advance
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