IS the incubation temperature for waterfowl the same as for chickens?

Domesticated ducks and geese are different species, and also different from chickens. The incubation temperature for their eggs varies slightly, but cannot be crucial because waterfowl eggs hatch quite happily under broody hens. However, since temperature can be controlled very accurately in a forced air incubator, it makes sense to use the correct temperature of 37.30C for ducks and 37.20C for geese. The temperature is the same throughout the incubator.

In a still air incubator, the temperature is often given for a thermometer on a stand above the eggs. The temperature is lower on the floor of the incubator, and increases vertically because the warm air rises within the incubator space. The difference in temperature between the floor and the top of the egg is as much as 2-3 degrees for a large egg. The recommended air temperature for goose eggs is 38.4 0C at a point above the eggs, to give a core temperature of 37.2. As you can see, still air incubators are not particularly accurate with temperature. They do operate best if they are full of eggs, and when the operator learns how the incubator behaves, through experience.

How long does it take the incubator to warm up?

If you know how the incubator runs, then 24 hours is sufficient, in a well insulated room (see Terry Beebe's article in the January edition of Smallholder) If you have a new incubator, run it for 2-3 day before setting eggs to check how it behaves. Also test the thermometer in several different positions/ heights if it is a still air incubator. This way you will find out if there are 'hot spots' and cool spots in the incubator. These will tend to even out if the incubator is full of eggs. Also, if there is a heat gradient, move the eggs' positions around the incubator over the whole incubation period to even out any temperature errors for each egg.

Check the thermometer itself. If the thermometer supplied uses alcohol (usually died pink or red), then get another mercury one. A hairline crack in an alcohol thermometer can lose liquid; the thermometer then under-registers and the incubator temperature may be adjusted upwards manually with disastrous results. Mercury thermometers are more reliable, but can suffer from separation of the liquid mercury which should be fixed.

Test the thermometer's accuracy by placing a clinical thermometer in the incubator as well; it's a good, independent check.

What happens if I get the temperature wrong?

Overheating eggs to core temperature 39.40C will kill the embryo. Try to keep the incubator at the optimal temperature of 37.1 - 37.20C. Overheating by one degree at the setting stage will kill everything at that point - or cause problems later. During the first few days, the embryo has to develop the blood vessels which will become the heart; also the extra-embryonic membranes are forming, and numerous complex processes taking place. By just four days of incubation, the embryo has eyes, brain and heart clearly visible. Also the amnion and yolk sac membranes are well developed. If things go wrong at this point, the embryo is considerably weakened. Forced air incubators are therefore much the best as setters because they maintain an even temperature. Really hard-to-hatch eggs, such as Call ducks, are best started under broody hens which get everything right.

A low temperature can be just as lethal as a high temperature and certainly does not compensate for any earlier overheating. Hatches are also poor when the temperature has been too low throughout incubation. Ducklings and goslings will have failed to resorb the yolk sac and there will be many 'dead in shell'.

If there is a power cut, will the eggs be no good?

Power cuts are pretty infrequent but, in my experience, they are nearly always in spring! If the power cut is notified in advance, then the way round that is to put as many eggs under broody birds as possible. If your house is warmed by a solid fuel stove, then store the eggs by the stove, or in the airing cupboard, during the power cut. But do monitor the temperature.

If no warm place in the house is available, put all the eggs together in a cardboard box and wrap it up in a duvet, to get as much insulation as possible. Eggs near hatching generate their own metabolic heat, keep each other warm, and will not suffer. BUT they do have increased oxygen demand at this point, so be careful. Eggs which have been set only a week or two will probably not suffer at all, even if they are out of the incubator for several hours (wrapped up of course) and have gone quite cold. Don't give up on eggs even if they feel very cold - for example when a broody has deserted. Always put them back in the incubator and see what happens. There is nothing to lose by doing this; quite often, the hatch is fine, just a day late.

Don't transport the eggs to another incubator in a different area. Shaking of the eggs in transit will kill the embryo in earlier stages of development. Eggs near hatching will be less severely affected.

How do I clean dirty eggs?

If eggs are dirty, don't use them. It is much better to use clean eggs in the first place. Germs can penetrate a very dirty shell. There is no point in growing bacterial colonies inside eggs which will then go bad and explode in the incubator. Give your birds nesting places with plenty of clean litter such as wood shavings and chopped straw (such as Sundown). It is better to preserve the outer layer of the egg - the cuticle - intact. This is especially important for natural hatching because the cuticle is a protective layer designed to keep out harmful bacteria. This is essential in a natural nest. Washing removes this layer.

Where eggs are hard to hatch due to retention of water, removal of the cuticle, for use in a clean incubator, can be beneficial. As you can see, decisions on incubation technique must come with experience in hatching the birds, with local climate, the incubator type and all the other variables involved in water loss and viability. This topic was covered in detail in Smallholder, March 2006 If the eggs are washed, use warm water (hand hot: around 40-450C) and this will prevent the egg contracting and drawing water and harmful bacteria through the shell pores. Egg sanitiser powder can be obtained from specialist companies such as Interhatch. For smaller batches of clean eggs in a clean incubator, this is not necessary. Just use running, clean, warm water to wash any harmful bacteria away whilst using a nail brush to gently clean the shell.

Do I have to put the eggs in the incubator as soon as they are laid?

No. The aim is to have a synchronised hatch. It is far better for the birds if they hatch together and have companions to keep each other warm and happy and to imprint upon. This is especially important with waterfowl. It is not kind to rear one bird which imprints just on its owner. Always have bird companions.

It is best to set eggs when they have rested for at least one day, and are up to 10 days old. So from one female, a clutch would be a maximum of 9 eggs. Eggs should, of course, be collected and cleaned daily. They are stored in a cool room at around 12 degrees C so that development does not start until their temperature is raised to 37.2. Store vertically, with the blunt end uppermost. Before setting, the egg temperature should be raised overnight to 20-250C before putting them in incubator. This is to prevent the yolk membrane rupturing with rapid expansion on a rapid rise in temperature.

Which way are the eggs turned?

Eggs must be turned at least three times a day, in an opposite direction each time. In natural nests, waterfowl turn their eggs around once an hour. The turning tends to be random, and is a shuffling rather than a deliberate turn. However, a goose will deliberately put her head over an egg, tuck her bill under it on the far side, and turn it end over end.

Do keep a recording sheet with the date of setting, expected date of hatch, and a record of the turns (left then right) in a manually operated incubator. Of course, the automatic turners will do all that turning for you, but it should be stopped from turning around day 25, or the eggs removed to a hatcher.

Turning must be done in an opposite direction each time otherwise the internal structure of the egg may become disrupted. It is especially important to get it right during the first few days of incubation to allow new nutrients to come in contact with the developing cells.

How long do the eggs take to hatch?

Waterfowl eggs take longer to hatch than chickens. The incubation period varies with the species. Ducks mostly pip and hatch between 28-29 days. Call ducks can hatch at 26 days. Geese take between 28 and 32 days; the Muscovy needs 33-35 days. The actual time depends upon variables such as water weight loss, age of the egg when set, and viability of the embryo. Fresh eggs from unrelated birds, with correct weight loss hatch earlier than those with problems. However, expect a hatch to be complete over a 2-3 day period.

How do I know if the eggs are fertile?

It is important to candle eggs to check if they are fertile, and also to see if they are developing well. Any eggs which are going bad must be removed otherwise they can infect the whole incubator. Any cracked eggs can also be seen and discarded. Buy a candling lamp. It saves a lot of problems Candling means that a light is shone through the egg in a dark room. It is also very useful to monitor the growth of the air sac as the egg loses water. However hi-tech your incubator, the numerous variables involved in water loss mean that observation is essential for success.

Do waterfowl eggs need higher humidity? Ducks and geese live in wet places.

Nest of birds have fairly high humidity, measured at around 60%. However, this varies according to the weather and climate, nesting materials and nesting site. Waterfowl do build their nests on dry sites. In wet weather, even naturally brooded eggs may fail to hatch due to insufficient water loss. Eggs may also dehydrate far too much in a dry spell.

Waterfowl eggs will not hatch in an incubator maintained at RH 60. Some texts still recommend RH 50 - 55. This may be suitable for large commercial incubators (of which I have no experience) but will result in failure for most waterfowl eggs in small incubators where the exchange of air is quite small.

Always read the manufacturer's instructions about adding water to the water trays of the incubator, but bear in mind that this is for chickens. In general, water is not needed in the incubator and RH may fall to between 24 and 37, depending on the ambient RH. Water is generally added in the last few days before hatching. It is needed when the birds pip, otherwise they can get glued to the shell, especially if all the albumen has not been absorbed when they have not lost enough weight and water. At pipping, RH of at least 60 is desirable and is difficult to achieve this without increasing the area of potential evaporation e.g. with a wet cloth Humidity is a complex problem. Certain types of eggs such as Chinese and Runner ducks need a higher humidity than hard-to-hatch eggs such as Brecon Buffs and Rouen. So mixing up different types of eggs in one incubator and treating them all in the same way will not be successful for all of them. For more information about humidity and weight loss refer back to Smallholder March 2006 and The Domestic Duck.

Should I help the eggs to hatch?

No. When the duckling first pips the shell, it is not ready. Usually, it needs 1-2 days to complete hatching. The yolk sac must be drawn inside the body and blood from the veins absorbed first. If you interfere, the duckling will bleed. Only hatch a duckling which has completed a full turn around the shell and seems to be stuck. Occasionally, the end of the egg shell is not flipped off, and the bird should be helped out. Otherwise - don't interfere. Birds which fail to hatch themselves are likely to have something wrong with them.

Occasionally birds pip at the wrong end of the shell. These should be helped eventually. They usually take longer to hatch than normally positioned birds.

Can I set and hatch in the same incubator?

Although incubator manufacturers say that their cabinet incubators can do both, I don't recommend it. Moving air dries out eggs as they pip and glues them up. When they do hatch, the hatching fluff gets blasted round the whole incubator, is difficult to clean up, and becomes a bacterial hazard.

Use a forced air incubator as an incubator and keep it clean and for that purpose only.

Always hatch in a still air incubator. The humidity then can be raised much more effectively in the still air hatcher - and the main incubator also kept at the correct humidity as well. Use a small incubator like a Brinsea Polyhatch which can be easily cleaned and sterilised after each batch. If you have one incubator: set, incubate and hatch only one batch before sterilizing and starting again. Don't mix incubating and hatching.

It is very important to monitor the temperature in the last week and especially at hatching. The metabolic heat of the bird, and exertion at hatching, can raise the temperature of the eggs and a small hatcher to lethal levels. That's why you must be around at hatching time - to check temperature and humidity.

What is the best way to sterilise the hatcher?

Start off with hot water and washing up liquid. That is enough if cleaning is regular and thorough. Milton is also a good household product to use. Really dirty incubators should be cleaned with Virkon. This is a pink, soluble powder obtained in sachets from specialist poultry and incubator suppliers. Used correctly it is very safe.

Where can I get good hatching eggs?

In my experience, hatching eggs are sold largely to make money rather than from a genuine interest in a breed. If the supplier is a large scale commercial enterprise this is no problem: the product will have to be good for the company to stay in business. Breeder birds will be selected for fertility and fitness of purpose.

If you want good examples of pure breeds, the situation is different. Serious breeders and exhibitors of good strains rarely sell eggs. They are the people who know what the pure breeds should look like, and the birds come first. If you really want good examples of pure breeds, then adult breeder-quality birds should be purchased.

Hatching eggs can of course be bought on Ebay. These eggs are often advertised as pure breeds. Very few of these vendors appear to be people who I would call 'breeders'. Photographs of the 'parent birds' are used to advertise the eggs. In many cases the photos are genuine. In some cases they are pictures of pure breeds taken from magazines and other websites and used against Ebay's recommendations for good practice. They are fraudulent.

If the quality of the birds does not matter a great deal, and the price is reasonable, then of course everything is fine. I've known people get excellent guinea fowl eggs and Black East Indian eggs from Ebay. But there is no point in paying high prices for eggs where you do not know if: n they actually are from pure breed parents (the vendor may be mistaken about the quality of the birds; this happens); n the parents are mature, breeder birds; n they have been separated from other breeds for a sufficient length of time to hatch only pure breeds; n the parents are closely related; n they have been on a good breeder diet; n the eggs are less than 10 days old; n the eggs are fertile; n transport has harmed the eggs; frequently the membrane is disrupted in transit in larger eggs.

Regular sellers will try to ensure that they fulfil most of the criteria for producing good quality eggs, but these will rarely be from top-quality pure breeds.

'Fertile' hatching eggs really are a lottery, especially with Call ducks. These eggs are especially hard to hatch anyway. In the hands of a beginner, after transport, then they are unlikely to be successful. They are not worth buying in this way - certainly not at the prices that some have reached. Early in the season (Jan-March) the eggs are unlikely to be fertile anyway. They are good to sell but not to buy! The best time for setting and hatching Calls is between mid April and early June.

In summary - don't pay a lot for eggs that you really know nothing about. Also beware of buying eggs from abroad. Without a licence it is an illegal trade, and may also break biosecurity rules.

What is the likely hatch rate?

One cannot really say because there are so many variables. However, one must be prepared to look after the birds that do hatch. Ask advice from people who rear birds. Get a good book. Have all the equipment and space ready to look after them. Find the right food (see Sophie Edwards' article last edition).

Don't hatch birds if you don't know what will happen to them. If they are for your own use, or already ordered, all will be well. Don't expect to take large numbers of them to auctions. Sub-standard birds will not sell and will end up being culled.

Don't leave all the jobs of incubation and rearing to children unsupervised either. One has a duty of care to look after pet animals, now enshrined in legislation. The Animal Welfare Act received Royal Assent on 8 November 2006 This duty now requires owners to provide a suitable environment for captive animals, provide adequate food and water, provide protection from pain, injury and disease and provide conditions that allow animals to exhibit normal behaviour. To my mind, this also includes hatching out eggs. As I am sure readers of Smallholder will agree, they should be treated with respect, by someone who understands the processes.