Tuesday 1 March 2016

First chicks of 2016 hatch.

It's the meteorological start of Spring, the Roman New Year (Before the Julian Calendar in 44 BC), St. David's Day and the first batch of chicks are hatching. Things can only get better after the wettest, windiest, nastiest winter in living memory Spring isn't far away.

Breaking out!
On average it takes 21 days for a clutch of eggs to hatch, but there is variation, some hatch on day 20 and some on day 22, there's a normal distribution of hatching dates as with all biological phenomena. Hatching starts when a small puncture appears at the fat end of an egg. the chick has been hammering away inside with its, "egg tooth" to make a tiny hole. Up to now it's air supply was contained in the air sac at the fat end, just enough for it to get to this stage.

The chick uses a lot of energy to drill the hole and needs a rest for anything up to ten or twelve hours. The it starts to chip away at the in side of the shell round its circumference until the top of the shell pops off. The chick is still covered in membranes, it  needs to struggle out of them and the shell. High humidity is essential otherwise the membranes dry up, shrink and strangle the emerging chick.

First out
Number one left it's shell behind at 10.00 pm last night, this morning there were four hatched another six or so are "pipped" ( they have made the first hole). I set 24 eggs on 8th February, on 18th I "candled" them to see how many had a developing embryo; four were clear or infertile and one cracked when I dropped it so 83 per cent were fertile.

Not all of the fertile eggs hatch, some die in the shell for a whole range of reasons and some only get half way out. So don't count your chickens........... is good advice.

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