Question about genetics, deformities & line breeding

[Farmer Viola]

Looking for a knowledgeable genetic / breeding expert to give me some advice!

A couple of chicks I have are showing slight deformities of the skull. The beak starts to turn towards the right around the nostril area. So far, the top and bottom beaks are growing together and not apart (scissor beak).

They are 6 weeks old now (3wk in photos). They did not hatch with this, it developed around 3 weeks old. 2 of 14 were affected.






In addition, I also have 1 chick who died in-shell with a similar deformity. only this 1 chick was noticeably deformed (of 12) at hatch, it died in shell on day 22.

Again, the other crooked beak chicks did not hatch this way, it developed later.



I have seen it in 2 different hatches so far, different incubators, same genetic source, so I am thinking that it is not related to incubation conditions..

• What could cause this crooked beak?
• How can I avoid this cropping up in future chicks? (obviously, these 2 will never be bred)
• Can anyone give me information about the effects of line breeding?
  is this what I am seeing, or could it be something else?

 

[centrarchid]

What you are seeing is not caused by linebreeding per se. Rather it is inbreeding at the level of locus were parent being bred back is likely heterozygous for recessive allele causing problem observed. I have similar problem and continue the linebreeding. You can use the linebreeding to ID carriers of the deleterious allele so that in the end when you reset line you can use individuals that are known not to be carriers employing progeny testing. With care you can actually use inbreeding to your advantage for removing a given allele.

 

[Farmer Viola]

What you are seeing is not caused by linebreeding per se. Rather it is inbreeding at the level of locus were parent being bred back is likely heterozygous for recessive allele causing problem observed. I have similar problem and continue the linebreeding. You can use the linebreeding to ID carriers of the deleterious allele so that in the end when you reset line you can use individuals that are known not to be carriers employing progeny testing. With care you can actually use inbreeding to your advantage for removing a given allele.

Thanks. I am going to re-read your paragraph 20 times to understand it, hah.

I do not have the parent stock, I won't even create this exact pairing again, but the chicks could carry it recessively..
I am relieved to know that I can be allowed to continue linebreeding the line safely. Thank you!

 

[centrarchid]

When I get back from work I can make a graphic representation.