Transporting and Incubating fertile eggs

This page is to provide important information relating to purchasing fertile eggs.

Evans Chickens are not intending to put anyone off buying fertile eggs (regardless of the transport method) but merely want to provide information, so the risks are known and the hatch rate expectations are realistic.

With the renewed interest in pure breed chickens many people are buying fertile eggs to pop under a broody hen in their backyard or for hatching out in an incubator.  After some research, people quickly discover that some breeds and bloodlines aren’t readily accessible. They then work out that they can purchase fertile eggs and have them transported using Australia Post. This is all true, but there are risks involved.

Egg fertility is pre-determined (to a certain degree) by the genetics of the parent breeding stock and the quality of the feed given to them during the laying period. Most responsible chicken breeders test fertility levels before selling eggs, and over 80-85% is considered reasonable.

Egg fertility is largely determined by a combination of factors, including:

  • The health of the parent birds;
  • The diet of the rooster and hens, from growing up as chicks through to breeding rations;
  • Successful development of the reproductive organs (a rooster can still perform his roosterly duties but be infertile, for example);
  • The ratio of rooster to hens (if there are too many girls, the rooster may not ‘cover’ all his girls adequately)
  • Seasonal fluctuations in fertility;
  • Genetics (inbreeding can affect future generation fertility rates);
  • Egg collection and storage,
  • Egg age upon setting,
  • Reliability of the incubator at holding temperature and humidity and the skills of the operator,
  • Transportation (if not setting/incubating at the same location as the eggs are laid).

It is generally accepted that anyone storing fertile eggs, store them in clean egg cartons tilted on an angle and turned at least twice daily. Turning of the eggs is important to prevent the egg yolk from sticking to the shell. Eggs should be stored in a cool, dark place

As a buyer you should be able to ask about the bloodlines of your eggs (if this is important to you), diet, fertility rates and hatching rates prior to purchase.

Methods to determine whether a resulting egg is, in fact, fertile

  • Incubating a fertile egg- a healthy, fertile egg will develop (at least partly) into a chick.
  • Cracking it open and looking for the 3-4mm embryonic spot. Doing this will, of course, render the egg useless for hatching.

If you are cracking an egg open in a bowl to check for fertility, look for the characteristic ‘bulls-eye’ on the right hand egg yolk.

Fertile Egg Yolk
Fertile Egg Yolk


Using Australia Post to get them sent to you

Assuming that all care is taken in the selection, storing and packing of eggs by the seller, the resulting hatch rate lies in the hands of Australia Post and in your incubator.

Once you get them home

All fertile eggs which are transported long distances (or posted) may need to rest as they may have had a rough time getting to you.

Obviously you may decide that this is unnecessary if they have only travelled a relatively short distance. It is a good idea to candle the eggs before setting them. The first thing to look for is hairline cracks, often it is best to cut your losses a lot of the time and throw them away.

Secondly, the air sacks are normally small, at the end of the egg and should be attached to the egg shell. Air sacks can become ‘scrambled’, which means that they can fragment/break apart or ‘float’ inside the egg, which more often than not means that they will not hatch. These eggs will need to be discarded.

What is considered a good hatch rate?

If you tell the average person that your hatch rate is 100% then they assume you mean that you set 100 eggs and got 100 chicks. In reality they are talking about number chicks hatched from the eggs that are still viable in the incubator at day 18, not the number of eggs that they started with at day one.  Hatch rate is different to set rate.

For example,  I set 100 eggs and 15% are clear (not fertile) and get discarded at day ten. When I put the incubator into lock down at day 18, I may discard another 10 eggs as they have not continued to develop. The other 75 hatch then the set rate is 75%. I could say that I hatched 100% of all fertile eggs but the set rate is still only 75% of the the eggs I put in.

We we incubate our own eggs here at Evans Chickens on average we achieve 70% viable chicks from the number of eggs placed in the incubator on day one. Fertility is usually around 80-90%, but as with all animals not all fertilized eggs develop into viable embryos. If you collect your eggs from us here in Maraylya, you should be able to achieve these sort of figures if your incubator is reliable and well calibrated for temperature and humidity.

Generally, it is a realistic goal to have 6 hatchlings/chicks per dozen eggs, especially for a breed/colour that you normally couldn’t access using other methods. This number may be higher or lower depending on incubation methods and factors listed above. Work on the principle  if you have eggs mailed, a realistic goal is 2 to 6 healthy hatchling from a dozen eggs, with all other factors being equal. Although this does seem low, it is a risk that buyers need to understand to avoid disappointment due to overly high expectations.

Is it worth it?

We personally (and a lot of other poultry keepers) would say yes. Some hatches you will have much higher hatch rates, some quite low. Some you will have are mostly rooster, others mostly hens. Buy a good quality incubator, it is worth the investment.  You take the good with the bad. But like most things in life, the decision to buy fertile eggs is about making an informed decision…

Hopefully you now have that information and make your decision…