Author Topic: Cross beak - genetic, environment...what?  (Read 12666 times)

Susan Mouw

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Re: Cross beak - genetic, environment...what?
« Reply #15 on: May 21, 2016, 10:49:37 AM »
But wouldn't dominance mean it'd be easier to breed around in poultry? Because a dominant gene can't help but express itself, and than you at least know what you're dealing with. Where as recessive genes can hide for generations, and pop out of the wood work when you pair certain birds/families and least expect it. A good reminder why test mating is so important though. Mammals are very different than avians, wow... My brain was not ready to look over that paper this morning Susan. lol Need more java, maybe more brain.  ::) haha



It is the incomplete penetrance that is the bugger.  With incomplete penetrance, you can have an animal that carries the genetic makeup of the trait (genotype), but not display any, or only a very mild, symptom (phenotype).  So, if cross beak is an incomplete penetrance, you could have a hen or a cockerel that carries the gene(s) for cross-beak, but neither one show it.  You'd have no reason to test breed for it, because neither parent was showing any signs of it.  The "good" thing about it being recessive is that, if one chick does show up as cross-beak, then you know both parents are carriers. 

With a dominant trait, like TVD in Labs, neither parent could show any signs of it, but one parent could have the genetic makeup.  If even one pup shows up with TVD - or even mild regurgitation, or murmur - then you know at least one of the parents has it.  Since it only takes one to produce it (dominant), now you have to identify which parent is the source and with incomplete penetrance, you can breed a lot of pups before you produce another pup that shows signs of TVD.  It is one of the heartbreaks in Labrador Retrievers.

As far as the paper goes - think how much coffee I needed to write that!  lol
Susan Mouw
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Clif Redden

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Re: Cross beak - genetic, environment...what?
« Reply #16 on: June 07, 2016, 05:54:27 PM »
Chicks hatched in incubators have a number of faults, some you can see  example cross beak, some you can't  for example, under developed immune systems,  the list goes on. I have hatched a huge amount of chicks using hens, I have never had a cross beak from under a hen.

Jim Morris

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Re: Cross beak - genetic, environment...what?
« Reply #17 on: September 18, 2016, 06:15:34 PM »
I have a Splash Wheaten cockerel that I hatched back in January 2016. He is a decent looking bird and I wanted to get some more Splash Wheaten pullets to pair up with him.  So I put him over my Blue Wheaten hens,  one of which is his mother.  I hatched out 15 healthy chicks.  I had posted a picture of them on the Ameraucana Chickens FB page.  I had all intentions of growing these out,  but after posting a picture on the Ameraucana Chickens FB page to beat about them,  a lady contacted me wanting to purchase them.  I sold them to her and after about 10 days she contacted me and sent pictures of two chicks that had developed cross beak. I hatched and sold around 400 chicks the spring  of 2016 and noone reported any issues of cross beak.  So I am assuming that my Splash Wheaten cockerel is carrying the recessive gene as well as his mother which I am sure he was covering.  I have pulled the Splash Wheaten cockerel and put my Blue Wheaten Rooster back over the hens.  I have 42 eggs in the incubator that are  from the hens being covered my the Splash Wheaten cockerel.   I will be growing them  out until they are at least 12 weeks old to see if any of these have cross break issues.  Feeling a little disappointed,  but glad to figure this out now rather than in the spring after hatching white a few. 

Don

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Re: Cross beak - genetic, environment...what?
« Reply #18 on: September 18, 2016, 10:01:34 PM »
Jim,  I don't think that a few cross beaks a year is very unusual when you hatch in large numbers.  Whether its incubator issues or purely genetic is hard to know for sure.  You can always test mate birds to see if they are reproduce the same issue.  I agree that the S/W male and his mother would be a prime suspect if its a genetic issue.  You might pull her out and put her in another pen if you want to mark her eggs.  And you might want to be  watchful mating him with his offspring.  You might be able to find another SW male from a similar line if you still want to produce more SWs.  I don't know if there are many folks that have concentrated on breeding SW/SW.  This mating will dilute the color.  But we don't know if this might create other issues as well.  I think we have a lot to learn about the Splash Wheaten variety still.  Keep up the good work.  They deserve more attention. 
Don Cash
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Jim Morris

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Re: Cross beak - genetic, environment...what?
« Reply #19 on: September 21, 2016, 11:06:43 PM »
Question for you Don.  You said  that the SW to SW might dilute the color. Are you referring to the pullets creamy wheat color,  or the Blue and red in the males.  I was hoping to get enough pullets to get a small breeding pen of Splash Wheatens started. 

Don

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Re: Cross beak - genetic, environment...what?
« Reply #20 on: September 22, 2016, 08:28:26 AM »
Jim,  You should be able to get some good females from a first generation SW/SW mating.  I was thinking more about the Blue/black and Red coloring in the SW males.  But we really don't know if the female color will be changed or diluted further with SW/SW matings.  Since the entire Wheaten variety presents dimorphic coloring male and female, it may not change the "wheaten" coloring on the females. Though it might  increase the white in the females tails and wings.  But that is part of what we will hope to find in the next few years with many folks working with this new color.  Blue is a dilute and SW is a double dilute gene.  So I wonder if this gene changes other things in the offspring.  You might talk to some of the Old English Red Pyle breeders to see if they have any experience with this mating.       
Don Cash
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