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Author Topic: Why Do Hens Lay Unfertilised Eggs ?  (Read 9661 times)

Offline neilep

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Why Do Hens Lay Unfertilised Eggs ?
« on: 30/08/2012 20:59:38 »
Dear Henologists and KFCologists*

As a sheepy I of course luff eggs !....eggs are like...well great..they are my all time favourite oval shaped eggy things that come from a chickens bum !*

I luff eggs ewe luff eggs we all luff eggs ! Eggs as ewe know were invented in 1654 by Mr M. BreeOh as a cure for his rather sad Hen Chasseur who at the time was suffering a terrible bout of the runs. So..he concocted a simple vessel to contain the spillages. Here, lookee see !


A True Bona-Fide Photo Of Happy Chicken Chasseur Sitting On Her New Eggs In 1654

Nice eh ?


Ever since then, the idea went viral and all Hens lay eggs and they what do they do ?...they sit on em !....

Now, ewe can imagine that a Hen must invest a fair bit of time, effort, energy and resources to lay these all the time..agreed ?..yes !!....................so...ewe'd think it make sense to just lay them when they are fertilised !...wouldn't ewe ?.......wrong !!.....we are talking chickens here.......I have a cabbage with a higher IQ in my fridge !

So, why do chickens lay unfertilised eggs ?..itís not energy efficient for the chicken is it ?

whajafink ?

Cos, I donít know !!...and I want to know and I if do know I can tell my kids and they will think I am klevur !


Ta

Hugs & Shmishes


mwah mwah mwah !!


Neil
Czechoslovakian Chickens Check Cheques
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx


* Other equally well branded 'ologists' are also available
* Not True. We all know eggs are delivered by the chicken fairy.
« Last Edit: 30/08/2012 21:02:29 by neilep »


 

Offline RD

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #1 on: 31/08/2012 01:00:11 »
Looks like a trait which has been artificially selected for rather than by natural selection.

Quote
As opposed to artificial selection, in which humans favor specific traits, in natural selection the environment acts as a sieve through which only certain variations can pass.
https://en.wikipedia.org/wiki/Artificial_selection
« Last Edit: 31/08/2012 01:05:00 by RD »
 

Offline neilep

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #2 on: 31/08/2012 02:13:19 »
Looks like a trait which has been artificially selected for rather than by natural selection.

Quote
As opposed to artificial selection, in which humans favor specific traits, in natural selection the environment acts as a sieve through which only certain variations can pass.
https://en.wikipedia.org/wiki/Artificial_selection

Thank ewe RD !.....It's a sound proposition. One that I thought  might crop up !....I love me chicken..I love me eggs !....not happy about the forced breeding to make a chicken lay an egg though........I expect the public get what the public wants

Is there any historical data prior our ability to selectively breed ?





« Last Edit: 31/08/2012 02:15:39 by neilep »
 

Offline CliffordK

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #3 on: 31/08/2012 03:33:17 »
We always had free-range chickens.  So, the hens would make their nests somewhere up in the hay stacks.

The hens were smart enough to tell when someone had raided their nest, and would move, so we would continuously have to look for new nests.

Whenever we passed the local golf course on the bicycles, we'd pick up golf balls that were laying by the road.  And, put the golf balls under the hens.  And, they'd be happy to continually return to the nest of golf balls.

We never had any golf balls hatch though.

As far as the egg formation and fertilization process, the formation of the egg yolk begins before the egg is fertilized.  An option might be to just abort the egg formation process if it isn't fertilized, but apparently eggs continue through the egg formation process to the end.  I would assume this would be true with other birds too.

Quote from: http://www buzzle com/articles/how-are-chicken-eggs-fertilized.html
The eggs are formed as yolk, in the ovaries of the hen. A healthy young hen produces a single yolk in every 24 to 26 hours. This yolk, when released from the ovaries, travels to the infundibulum. If there are sperms in this funnel-shaped organ, the yolk will get fertilized (hens can retain sperms for around 10 to 48 hours). Once fertilized, the yolk passes through the same route, through which the sperm traveled to reach the infundibulum. The only difference is that the yolk travels in the reverse direction and completes its structure to form a proper egg, during the course of this journey. The yolk gets surrounded by the egg white in the magnum, whereas the formation of the shell membrane starts in the isthmus. From there the yolk (covered with egg white) travels to the shell gland, where the shell formation is completed and the shell gets hardened. The egg is ready to be laid, which is usually done in the middle of the day. Once the fertilized egg is laid, the hen is ready to start with the formation of a new egg.

Many store bought eggs are unfertilized because blood spots are not popular with the consumers.

Some plants require fertilization.  Others don't.  I believe corn is perfectly happy without fertilization, and thus the "male sterile" corn is often used for hybridization.

(sorry source above is linked without periods).
 

Offline RD

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #4 on: 31/08/2012 03:56:13 »
Is there any historical data prior our ability to selectively breed ?

Selective breeding (artificial selection) is also responsible for them being too meaty to fly ...

http://www.straightdope.com/columns/read/1433/why-cant-chickens-fly
 

Offline CliffordK

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #5 on: 31/08/2012 04:42:59 »
Your laying hens and eating chickens are generally different.

White Leghorn is the predominant laying variety in the USA.
Cornish Cross is a common meat variety.

Most laying hens can fly.
Well, at least they could fly if they weren't confined to a cubic foot box.

Not great flyers, somewhat like a grouse, but they can certainly get from the ground up to the rafters of a barn.

The Cornish Cross chickens may just be too fat to fly...  Wouldn't you think it was extra muscle?
 

Offline evan_au

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #6 on: 31/08/2012 10:00:36 »
In a "normal" population of free-range hens & roosters, I would imagine that most of the eggs would be fertilised, so there is no advantage in not laying them.

It is only in our artificial environment of single-sex egg factories that it seems a bit odd.

I have heard of rodents which live as solitary animals in a desert environment, which ovulate only after sex. Closely-related rodent species living in groups ovulate regularly, even without sex. However, a mammal egg is much smaller than a bird egg, so it may require less of a "production line".
http://www.thenakedscientists.com/HTML/content/news-archive/news/2643/
« Last Edit: 31/08/2012 10:55:10 by evan_au »
 

Offline neilep

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #7 on: 31/08/2012 13:26:41 »
We always had free-range chickens.  So, the hens would make their nests somewhere up in the hay stacks.

The hens were smart enough to tell when someone had raided their nest, and would move, so we would continuously have to look for new nests.

Whenever we passed the local golf course on the bicycles, we'd pick up golf balls that were laying by the road.  And, put the golf balls under the hens.  And, they'd be happy to continually return to the nest of golf balls.

We never had any golf balls hatch though.

As far as the egg formation and fertilization process, the formation of the egg yolk begins before the egg is fertilized.  An option might be to just abort the egg formation process if it isn't fertilized, but apparently eggs continue through the egg formation process to the end.  I would assume this would be true with other birds too.

Quote from: http://www buzzle com/articles/how-are-chicken-eggs-fertilized.html
The eggs are formed as yolk, in the ovaries of the hen. A healthy young hen produces a single yolk in every 24 to 26 hours. This yolk, when released from the ovaries, travels to the infundibulum. If there are sperms in this funnel-shaped organ, the yolk will get fertilized (hens can retain sperms for around 10 to 48 hours). Once fertilized, the yolk passes through the same route, through which the sperm traveled to reach the infundibulum. The only difference is that the yolk travels in the reverse direction and completes its structure to form a proper egg, during the course of this journey. The yolk gets surrounded by the egg white in the magnum, whereas the formation of the shell membrane starts in the isthmus. From there the yolk (covered with egg white) travels to the shell gland, where the shell formation is completed and the shell gets hardened. The egg is ready to be laid, which is usually done in the middle of the day. Once the fertilized egg is laid, the hen is ready to start with the formation of a new egg.

Many store bought eggs are unfertilized because blood spots are not popular with the consumers.

Some plants require fertilization.  Others don't.  I believe corn is perfectly happy without fertilization, and thus the "male sterile" corn is often used for hybridization.

(sorry source above is linked without periods).

Thank ewe for this information CliffordK.....Wouldn't it be prudent from an evolutionary point of view for chickens to abort non fertilised eggs..it simply must consume quite a fair bot of chiccky energy !!....or put it this way....What benefits are there for the chicken to carry on developing a non fertilised egg ?

Love the thought of chicckys sitting on golf balls !  :)
 

Offline neilep

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #8 on: 31/08/2012 13:28:40 »
Is there any historical data prior our ability to selectively breed ?

Selective breeding (artificial selection) is also responsible for them being too meaty to fly ...

http://www.straightdope.com/columns/read/1433/why-cant-chickens-fly

Thanks RD...so what we have done intentionally nature has probably done to the Ostrich, emu and kiwi etc
 

Offline neilep

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #9 on: 31/08/2012 13:36:14 »
In a "normal" population of free-range hens & roosters, I would imagine that most of the eggs would be fertilised, so there is no advantage in not laying them.

It is only in our artificial environment of single-sex egg factories that it seems a bit odd.

I have heard of rodents which live as solitary animals in a desert environment, which ovulate only after sex. Closely-related rodent species living in groups ovulate regularly, even without sex. However, a mammal egg is much smaller than a bird egg, so it may require less of a "production line".
http://www.thenakedscientists.com/HTML/content/news-archive/news/2643/

Thanks evan_au That is very interesting . Thanks also for the link to the archive feature.  I think the trigger ovulation is very neat !! It would make us blokes lives a lot easier !...once a month I'm always guilty !!  ;)
 

Offline SeanB

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #10 on: 02/09/2012 08:19:13 »
I used small white stones as a birth control method when I had racing pigeons. Otherwise they would breed all year round, and eat me out of house and home. Warm the stones up and check the eggs then swap them, and then they would sit for another month then kick them out, and try again.
 

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Re: Why Do Hens Lay Unfertilised Eggs ?
« Reply #10 on: 02/09/2012 08:19:13 »

 

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