Domestic Waterfowl Club.

Breeding ; Humidity Tables

Humidity + Errors

Humidity plays a vital role in the percentage of hatch and even more so in the quality of hatch. The combination of too high a humidity in both setter and hatcher can result in drowning the chicks in the shell. Too low humidity in incubator will result in 'dry sticks' Too high a humidity in hatcher during the first twenty-four to thirty-six hours can result in rough and unhealed navels, although this condition is more frequently due to excessive incubator temperature. Too low a humidity in the hatcher can result in chicks which pip but fail to get out of the shell.

  A suitable humidity must be maintained to prevent the eggs drying out too quickly or losing sufficient water. All incubators have one or more water containers, trays or troughs which should be kept topped up with water to maintain an appropriate humidity, according to the manufacturer's instructions. Use hand-hot (39 °C) water to prevent the temperature in the incubator dropping too dramatically when refilled. In hard water areas boiled or distilled water means that wicks etc. last longer . Do not move the incubator while containing water. In some incubators, a piece of cloth may be needed to act as a'wick'.

  Too much humidity at the wrong time is just as bad for a developing egg as too dry an atmosphere: an egg must lose a certain amount of water during incubation if the duckling is to emerge satisfactorily.

  Some incubators are supplied with a wet- and dry-bulb thermometer.The wet bulb is for obtaining readings of humidity. It is very difficult to obtain accurate readings with such a device and not recommended that they are used by beginners. It is often better to check humidity by assessing the effects on the egg,, rather than to obtain actual measurements.

  Relatively accurate electronic instruments for measuring humidity(called hygrometers) are now available but the most useful of these werequite expensive ( see ebay) . Manufacturers supply units which will control the humidity in certain of their incubators.

The eggs must have a suitable flow of air to supply enough oxygenfor the embryos to develop and to remove the carbon dioxide produced. The ventilation will, however, also affect both the humidity and the temperature; a high ventilation rate will carry more moist, warm air out of the incubator.

  Follow the guidance offered by the incubator manufacturer. Various authorities quote a wide range of suitable humidities but it is difficult to produce an exact humidity in the incubator and to measure it accurately. Ensure,,that the water tray never dries out completely and do not have a very humid atmosphere together with poor ventilation.If the eggs are in an egg tray on a dish cloth or piece of Hessian, do not add water to the material to make it damp. Also do not spray the eggs daily with a mist of water, although this has been recommended by some authorities. Ducks and Geese swim eggs don't.

  Humidity levels should be varied during incubation but it isdifficult to give precise advice. As a rule, during the first half of the incubation period, the humidity should be at a low to medium level;the second half requires a medium level of humidity. Some authorities recommend a dryer atmosphere around day 27 to help the duckling break into the air space. As soon as the eggs become 'pipped', with the duckling starting to break out of the shell, the humidity should be raised to a higher level for hatching. It is essential that the eggs lose 12-15% of their weight over the incubation period. Humidity that is too high or too low will cause too little or too much weight to be lost. Water loss can be monitored by measuring loss (by weighing the eggs) or by observing the size of the air space - using a technique called 'candling' . Measuring the loss of weight is probably the better technique to use but is more troublesome to carry out and requires a reasonably accurate balance. Candling requires some skill but is more easily learnt..
By removing a batch of eggs and weighing them at regular intervals, the loss in weight can be monitored and adjustments to humidity made. (It is better to measure the weight of several eggs and calculate the average loss per egg because the balance probably available is unlikely to be sufficiently accurate for small weights.) Ensure that the eggs are not excessively chilled when they are being weighed; measurements should be carried out quickly. A cloth in he scales helps prevent damage.

1. Eggs clear no blood

A. Eggs infertile due to 1. Males sterile or poor hatchability heredity in flock.
solution Careful Culling and flock Selection for high hatchaability.
2. Too many or too few males. Males fighting with each other.
Raise males together.
5 to 8 males per 100 females with heavy breeds. 8 to 13 males per 100 females for turkeys.
3. Males too old
Do not use old males, unless proved valuable breeders.
4. Inadequate nutrition or insufficient water (or water too cold) Flock may show
poor fleshing in males & females
Use properly balanced feed of high quality. Provide adequate waterers of good design well distributed, so that, all birds can have easy access to fresh water.
5. Birds too closely confined.
Provide adequate floor space per bird in housing.
6. Seasonal decline in fertility in late summer and fall
7. Interfering with eating and drinking
Dub males to prevent this problem, and also improve fertility.
8. Disease in the flock
B. Eggs damaged by being either badly chilled or overheated.
C. Eggs held too long or held under improper conditions of temperature and humidity,
Carry out approved disease control practice.
Gather eggs often, cool properly and quickly.

Proper conditions for egg holding be observed.

2. Eggs Candling clear.
A. Eggs over heated or held at too high temperature.
Gather eggs often. Coo! properly and quickly. Refer instructions for egg holding.
B. Improper incubator tem perature at earliest stage of incubation.
Check accuracy of thermometers, Operate incubator at proper temperature.
C. Improper fumigation too much fumigant, fumigant not cleared from machine soon enough or eggs fumigated in the incubation period
Refer instructions regarding fumigation of eggs in the incubator.
D. Breeding flock out of condition
Do not set eggs from  diseased birds, particularly those infected with pullorum or other salmocilla diseases.
E. Improper nutrition of flock.
Feed properly balanced ration of high quality.
F. Poor hatchability heredity in flock
Careful culling and flock selection for high hatchability, improve breeding for high hatchability.

3. Many dead germs
A. Temperature too high or too low in incubator
Check accuracy of thermometers. Operate incubator at proper temperature.
B. Lack of Ventilation
Provide adequate ventilation of the incubator at and proper openings of the Incubator rota vents.
C. Improper turning of eggs
Turn eggs at regular intervals.

4. Ducklings fully formed but dead without pipping.

Low average humidity in incubator, too low or too high a humidity at transfer time in the hatcher.
Maintain proper humidity levels throughout incubation and hatching cycle.

5. Eggs pipped but  dead in shell

A. Low average humidity. This is the most probable cause.
Maintain proper humidity levels throughout incubation & hatching cycle.
B. Inadequate ventilation or excessive fumigation during course of hatch.
Provide adequate ventilated room & proper openings of rota vents of machine.
C. Low average
Maintain proper temperature throughout incubating & hatching cycle.

6. Sticky chicks, chicks smeared with eggs contents

A Low average temperature
Use proper operating temperature.
B. Average humidity too high.
Maintain proper humidity levels throughout incubation and hatching cycle.
C. Inadequate ventilation or improper fumigation of eggs in incubator or excessive fumigation in the hatcher.
Provide adequate ventilation of the incubator room and proper opening of the incubator rota vents. Also refer instructions regarding fumigation.

7. Dry Sticks shell sticking to chicks
A. Eggs dried down too much.
Proper ventilation and humidity throughout incubation and hatching cycle.
B. Low humidity at hatching time.
Proper humidity levels throughout incubation and hatching cycle.

8. Chicks hatching too early with bloody navels.

Temperature too high.
Maintain proper temperature levels throughout incubating & hatching cycle.

9. Rough or poorly healed navals
A. high temperature or wide temperature variation, cubation and hatching cycle.
Maintain proper temperature levels throughout in
B. Excessive humidity in hatcher after transfer.
Use less humidity for first 24 to 36 hours after transfer.

10. Chicks too small
A. Low humidity.
Maintain proper humidity level throughout incubation & hatching cycle.

11. Large, soft bodies mushy chicks, dead on trays with bad odours.

A. Low average temperature
Maintain proper humidity level throughout incubation & hatching cycle.
B. Poor ventilation
Provide adequate ventilation of the incubation room& proper openings of the incubator and hatcher rota vents.
C. Omphalatia (vavel infection)
Thoroughly clean and fumigate hatcher between hatches Fumigate hatcher at double or triple strength between hatches until trouble eliminated then return to normal strength fumigation of hatcher between hatches. Fumigate eggs in incubator.

12. Weak chicks
A. Excessive fumigation in the hatcher
Do not permit temperature in hatcher to be too high. If chicks are to be held in hatcher, reduce temperature after hatch is completed.
B. Respiratory diseases as bronchitis
Provide adequate incubator room ventilation. Maintain adequate rota vent openings in hatcher.

13. Short down on chicks.
A. High temperature
Maintain proper temperature levels throughout incubation and hatching cycle.
B. Low humidity
Maintain proper humidity levels throughout incubating and hatching cycle.
C. Excessive ventilation at hatching time.
Reduce openings of hatcher rota-vents. Restrict opening of top ventilations. Do not restrict so far as to permit animal heat to build temperature above safe level.

14. Gasping chicks.
A. Average temperature too low.
See instructions on fumigation during the course of hatch.
B. Eggs held too long. Improper gathering, holding of eggs.
Carry out approved disease control practice.

15. Delayed hatch eggs not starting, to pip until 21 st day or later
A. Excessive temperature in hatcher.
Maintain correct temperature throughout incubation & hatching cycle.
B. Inadequate ventilation in hatcher.
Try not to hold eggs more than 3 days.

16. Draggy hatch some chicks early.
Improper gathering, holding of eggs.
Eggs must be gathered frequently, cooled quickly and held at proper temperature and humidity before setting.

17. Crippled and malformed chicks,
 Cross beak
Careful flock culling
 Missing eye
Abnormal & rare. May be due to excessive temperature
Matter of chance.
 Wry neck
Wry neck suspected as matter of nutrition. Not fully known.
D. Crooked toes
Improper temperature. This can also be caused by setting too few eggs per tray permitting too much freedom of movement to chicks.
Maintain proper temperature levels throughout incubating and hatching cycle. solution  Do not set too few eggs per tray.
E. Spraddle legs
Caused by hatching trays which are too smooth.
Use  cloth in hatch trays.

18. Malformed chicks or poor hatch.

Excessive number of malpositions among dead in shells
A. Improper turning or setting
Set eggs small end down only. Turn eggs at regular intervals eight times daily.
B. Inadequate ventilation
Provide adequate ventilation of the incubator room and proper openings of the incubator and hatcher rota-vents.
C. Abnormally high or Abnormally low incubator temperature.
Maintain proper temperature level throughout incubator cycle.
D. Insufficient moisture.
Maintain proper humidity level in the incubator.
E. Heredity & breeding
Careful culling & flock selection for high quality.
F. Improper nutrition
Use properly balanced feed of high quality.
G. Non-Pourous shell either from natural causes involved in heredity and nutrition or from foreign material on the shell.
Careful culling & flock selection, properly balanced feed, balance feed of high quality, proper care of eggs.
H. Damage to eggs in transit from one place to another
Hatching eggs must be sent in good quality well-protected egg cases, with small ends down. Avoid rough handling.

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