万思乐学V-Learn小西妈双语工程201801期406Max@20190429@Day386

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Incubation of chicken eggs - Day 1

We've thought it all through, bought the equipment, found our eggs and allowed them to 

'rest' while we bring our incubator up to the right temperature.

Now it's time to see what's happening at this very early stage of incubation.

When exactly is day 1 of incubation?

As a rough guide, if they go into the incubator in the early morning, I count that as day 1. However if they go in any time after mid-day, we count that as day 0 and the following day as day 1. An egg doesn't have a full day's development until it's been incubated for 24 hours.

We put our eggs in on Sunday at 5pm, so Monday is day 1.Incubation times aren't all that precise, though, so don't get too worried about it.

The process from the start of incubation to hatch usually takes 21 days.However, as we'll see later in the process this is not an exact science and hatches can take more or less time than this. I heart some chicks even hatch as late as Day 26.

What's going on in the egg today?

A rooster is the first step to a fertilised egg.

A rooster - the first step to successful incubation!

You might think nothing much is happening in the egg today - after all, it's only just gone into the incubator.

You couldn't be more wrong.

In fact, the egg starts to develop as soon as it's laid - provided, of course, that a rooster has been around to fertilise it. If there's no daddy, there's no baby.

As soon as the fertile egg is laid，cells begin to divide and will, if kept at the right temperature and humidity levels, start to develop today into an embryo. If they're not warmed thennothing will happen.

In a fertile egg which isn't incubated, the cluster of cells remains and if you open it at this point and look at the yolk, you'll see a pale circle with another, smaller circle in the middle.

This is the blastoderm and it's often referred to as the "bullseye". It looks a bit like a doughnut. It's a sign that the egg is fertile and it's from here the chick will develop.

It's only day 1 of incubation - what does the chick look like today?

At this stage it's really not a chick, just a collection of cells. Although things are happening they're not visible to the naked eye.

What's happening to the chick?

Despite this, the blastoderm - that collection of cells which will form the embryo - is developing, microscopically. The cells which will become the head, spine, blood vessels, nervous system and digestive system are already starting to divide.

What can we see if we candle at day 1?

Nothing. It's not wise to candle too early in the incubation process.There's nothing to see yet and you run the risk of damaging the fragile embryonic system.

This is what you'd see if you did. The slightly darker area on top is the yolk. Apart from that, the naked eye can't see anything going on.Candling at day 1 shows no results.

What should we be doing today?

1.Make absolutely sure the eggs are either lying on their side or are incubated with the pointed end facing downwards and the blunt end up. This is really, really important. If the eggs are stored the other way - with the pointed end uppermost - the eggs will not hatch. No ifs or buts - it won't happen.

2.Make sure the eggs are turned.It's also important to make sure that every egg is turned throughout incubation right up until day 18.

Why does this matter?

Early in the process there's a strong possibility that not turning will cause the developing embryo to stick to the shell membrane and be unable to grow.Later in development a chick may start to 'pip' but die at that point because not turning also affects the air cell which doesn't develop properly.So the chick itself develops but when it tries to 'pip' through the inner membrane, there's no air there for it to breathe.The hatchling will only pip if the air sack is properly developed.

How often should turning take place during incubation?

A hen sitting on eggs gets off them every day until around the end of day 18. She goes to feed and drink, and when she returns to the nest she moves the eggs.

Incubators with automatic turning devices

mimic that behaviour and turn by a small degree every hour or two, day and night.

If you're turning your eggs manually,it needs to be done at the very least three times a day and make sure they're marked so you know which way they should be.