Genetic changes

[Chris H]

I was just reading the post about the Angus defect where the calf has extra limbs. I've read about 'curly calf' in Shorthorns(or is that Maine?). There's IE, hypotrichosis, & diluter genes in Herefords, as well as other breeds.

Are there any gene mutations that improve a breed, and will breed true once developed? I know double-muscling is a trait that is desirable in some breeds but not others.

I was just looking up something and found a long list of genetic defects, http://beefmagazine.com/genetics/avoiding_worst_20100201, still nothing about a mutation that improves breeds.

 

[sim.-ang.king]

Depends how you look at it.
Some people might like a extra leg on their calves...more rump roast that way.

 

[Jessica06]

TH (tibial hemimelia) is bred for in club calves. The carriers are showier and more extreme. ie. Heat Wave

 

[inyati13]

The short answer is yes. Mutations are a fundamental part in the evolution of every organism. If you study the modern theories of evolution (which might get you a run off CT, ), it is a combination of mutations and several other mechanisms which together gradually change an organism over time so that it can adapt to changes in its habitat.

It is more difficult to become aware of beneficial mutations. But if a calf is borned with duplicated appendages as they are in DD, it is observed rather directly. To provide an example, here is the following that will demonstrate why it is unlikely that beneficial mutations are notived:

Oldtimer has 1,000 cows on the plains of Montana. One spring 80 years ago a bull calf was born with a dominant inheritance mutation. The mutation changes one gene in the bulls genome that produced a protein that allowed that bull to better utilize the grass on the arid plains. Oldtimer does not manage his herd so the bull calf grows up and breeds back to momma and sisters. Now we have several animals running in the herd that are homozygous dominant for the mutation that gives them an edge turning grass into protein. A horrible 5 year period comes, drought, snowy winters, etc. At the end, the only survivers are Oldtime's cattle with the beneficial mutation. No one would probably ever know. Oldtimer would find out that he has the only surviving cattle in the Rocky Mtn plains. Those cattle evolved to better adapt to their environment/habitat. That would be a beneficial mutation.

PS: I should state, that text books on evolution and speciation acknowledge that the vast number of occurring mutations are harmful. I cannot remember the estimated percentages. But it is like only 1 in a million mutations are thought to be beneficial.

 

[sizmic]

Being "polled" (hornless) is a genetic mutation, isn't it.

Sizmic

 

[aprille218]

Yes, being polled was a mutation. Also any color other than wild allele brown (dun) was a result of mutation.