Chicken Genetics

[Arielle]

Is chicken genetics really different than mammalian genetics? I regularly read, with dismissing tones, that what applies to dogs, or horses or sheep does not apply to chickens. With a degree in Animinal Science I did not remember the chicken genetics being different, though the focus was on dairy cattle. However, information evolves and I figured to go to a trusted source, the professor emeritus at the University of Maine.

Dr Robert Hawes kindly responded to my email inquiring about bird genetics.

" The genetics of fowl is no different than the genetics of mammals. The big difference is that in fowl the female is the heterogametic sex and the male is the homogametic sex. Just the reverse of mammals."

For the inquiring minds that want the truth.

 

[TShelton54]

Dr. Hawes is exactly right. The main difference is the selection of sex is reversed in birds. The basics are the same. Tim

 

[gallorojo]

It is different in numerous ways. Not totally different, but, certainly far more complicated in some ways. Mammals for example have basically only one pigment, while birds and reptiles have more than one. Also consider how common complex patterns are in birds, vs mammals. Your basic genetic studies will serve you very well in understanding the terminology and the mechanics, but it's simply much more complex with birds.

 

[Arielle]

 

[gallorojo]

I also wanted to add that really the BASICS of genetics and breeding/selection are the same for corn, fish, chickens , petunias, and dogs alike. The details will differ. If people dismiss the basics similarities out of hand, that's too bad. No, breeding chickens is not breeding horses, BUT, breeding is breeding, and fundamental principles apply to both.

 

[Arielle]

Selection of genes desired will increase the frequency of those genes in the next generation.

I come from a breed of horses where we breedi for useful ness and sport, not just a pretty face. Makes for complex breeding. Selection of the parents, influences the health and function of the offspring.

corn, squash, holstein, tulips, buckeyes, showgirls.

 

[Sonoran Silkies]

The more chromosome pairs, the more complicated...simply because more genes are involved. Another difference is different names for genes from one species to another, and that there are scientific names and names used by breeders.

 

[Arielle]

In horses we don't talk genes, we talk performance. ANd length of hip or leg, etc. Rarely color of coat, unless it's a QH.

So learning all the color genes in chickens is important and it fries my circuits! LOL At least looking at conformation I have the basic jist, just need to leanr the names of the parts of a chicken other than the meat cuts!

 

[Henk69]

The principles of genetics are the same.
But comparing mammals to birds/chickens:

Indeed XY for male mammals, XX for female mammals, ZZ for male birds, Zw for female birds.
(Not all mammals have the XY system though)

Birds have a lot of sexlinked genes for color, chickens also for feathergrowth and bantam size.
The red gene of cats is the only sexlinked mammal gene that comes to mind.

Chicken genes are rarely completely dominant, so mostly best in 2 doses. So to get an exhibition grade you should breed them pure and not cross colors that aren't compatible.

In chickens there is an extension range like in most domesticated mammals (dominant black, recessive red)
The "agouti" range is not yet found but there is a gene that acts similar (columbian Co)

Chickens do not have the typical pied genes that a lot of other domesticated animals have. Only mottled.

 

[Arielle]

Welcome Henk,

Very interesting stuff.

Since the DUtch are among the best horse breeders and flower breeders in the world, I suspect chickens and cattle are up there too.

I learned my horse breeding criteria from the Dutch. THe data is collected by trained personnel and the 26 traits are put into a data base. For those who are new to all this the traits are the expression of a number of genes acting together. Length of neck, length of back, angle of hip.

It is all about selection.