th phenotypes

[oakview]

I wasn't going back as far as the Sables, etc, just including more recent years or the post-test development years.  Over the past several years, there have been tons of cattle that trace to Improver (many through Improver 57 as was suggested in an earlier post), but the top winners have been TH free.  The point is that I do not believe that you have to include the TH gene to get a good or great one.  I agree that most of the steer show winners would be smaller framed than most of the breeding cattle winners or commercial cattle for that matter.  However, I maintain that the TH gene just goes along with many popular club calf type bulls, but is not a prerequisite for siring a good show steer.  I can't believe the TH gene just automatically rides along with the genes controlling frame size, either.  Those of you who deal with club calves surely can think of a good sire that is TH or PHA free. 

 

[aj]

As I understand it....you can think of a good bull who is th and pha free but their offspring won't win a steer show......period.

 

[chambero]

They do slick shear shows in Tx with regularity.

 

[vc]

I was not going to post anything on this topic but the more I read the other post the more it got me thinking, here are some of my thoughts, probably not worth a plug nickel but oh-well.

Since they do not test steers, one can only make the assumption that the steers that win are TH, they may have been sired by a TH carrier that does not necessarily make them a carrier. This claim also contradicts the other common statement “Half the HeatWave calves out there are sired by the clean-up bull and just called a HeatWave”, I know I have seen that claim posted on this site close to a 100 times over the years.
Since most of the top bulls are composites, it is just as easy to explain away the inconsistency of their offspring, to being a crossbred as it is to TH.
You hear how the commercial guys like the F1’s, but do not like the inconsistency or the loss of heterocyst from an F1 bred to an F1. This could help explain big boned to fined bone, hair to no hair or any of the other inconsistencies, how do you explain no bone but hair, he has less TH?
The top steers may all be TH, but to make that claim without any solid proof does not seem realistic. Take the bulls that are clean that still have the look, if steered how would they have performed in the ring? I think if you tested all the steers that win you would probably find a mix of positive and negative steers, it may not be 50/50, but there would be a mix.

 

[JCattleCo]

So how heretible is th?? I've got angus based cows with no th background whatsoever so would a 50% Maine th carrier bull like bojo be more likely to produce th offspring than the 65% angus monopoly even though they are both carriers?

 

[oakview]

The offspring of a TH carrier bull, assuming he is bred to TH free cows, would have a 50/50 chance of being TH carriers, but none would show physical abnormalities.  The gene would still be present in 50% of the calves, regardless whether the mothers were Angus or Scotch Highland.

 

[aj]

Zach or somebody always said that the really good steers were double carriers.

 

[JCattleCo]

That's why heat wave / Irish whiskeys are winning everywhere

 

[DLD]

Saying that only TH carriers, or even more so double (TH/PHA) carriers can win steer shows, is just about as correct as those that say they can determine a carrier just by looking at them.  Both are just somebodies theory - at least until they put their money where their mouth is and prove themselves true... 'til then, they remain pure speculation.

No question, lots of the winning steers the past several years trace to carrier genetics, but think about the tremendous amount of promotion behind those genetics, and how many cows are getting bred that way... Sheer numbers means steers with carrier genetics are going to win quite a bit.

 

[RyanChandler]

The offspring of a TH carrier bull, assuming he is bred to TH free cows, would have a 50/50 chance of being TH carriers, but none would show physical abnormalities.  The gene would still be present in 50% of the calves, regardless whether the mothers were Angus or Scotch Highland.

Theoretically

 

[KSUwildcat2009]

The offspring of a TH carrier bull, assuming he is bred to TH free cows, would have a 50/50 chance of being TH carriers, but none would show physical abnormalities.  The gene would still be present in 50% of the calves, regardless whether the mothers were Angus or Scotch Highland.

Theoretically

What do you mean by Theoretically?

 

[aj]

The free market has dictated that you cannot win a steer show with a calf that is not a th carrier. Other wise the th free genetics would take over....PERIOD. If heetseeker wasn't a th carrier he would be worthless. Probably....fun to think about.

 

[vet tech]

I don't believe the double carrier winners are as prominent as people think, sure there are some. I would say of the carriers that are winning only close to 10% are double carriers if that. At least the steers that win major shows. Just a guess but I you see te steer that win the huge shows like Denver, fort worth, lville etc you can track down the donor dam very easily and find out there status on th and Pha...

 

[sackshowcattle]

here is one word for people to think about who say th has a phenotype. THRILLER. 95 perecent of the people that go off the look of a calf would have lost money if they bet on him. Looks the part and double clean. What would be fun is if they would blood test at these terminal shows to see how many are carriers. It would be interesting to see if the look crowd is wrong or if only carriers are making it to the ring. Either carrier and non carriers are making it to the ring or there are a ton of non carriers going to the sale barn.

 

[kfacres]

The offspring of a TH carrier bull, assuming he is bred to TH free cows, would have a 50/50 chance of being TH carriers, but none would show physical abnormalities.  The gene would still be present in 50% of the calves, regardless whether the mothers were Angus or Scotch Highland.

Theoretically

What do you mean by Theoretically?

Some bulls, or animals are 'hotter' than others.  For instance-- PHAC bull that was unknown at the time- used several years ago- tested the first 9 calves born-- all Carrier... From then- he ended up siring less than 5 non carriers out of 30.  

PHAC cow- 6 calves- never had a non carrier yet- always mated to clean bulls

THC cow- always mated to clean bulls-- not had a carrier yet-- 7 calves.

according to the standard 50/50 rule-- those should not be happening...

 

[KSUwildcat2009]

The offspring of a TH carrier bull, assuming he is bred to TH free cows, would have a 50/50 chance of being TH carriers, but none would show physical abnormalities.  The gene would still be present in 50% of the calves, regardless whether the mothers were Angus or Scotch Highland.

Theoretically

What do you mean by Theoretically?

Some bulls, or animals are 'hotter' than others.  For instance-- PHAC bull that was unknown at the time- used several years ago- tested the first 9 calves born-- all Carrier... From then- he ended up siring less than 5 non carriers out of 30.  

PHAC cow- 6 calves- never had a non carrier yet- always mated to clean bulls

THC cow- always mated to clean bulls-- not had a carrier yet-- 7 calves.

according to the standard 50/50 rule-- those should not be happening...

There is no such thing as a "hotter" carrier.  It's all based on probabilities.  Each calf out of a THC x THF mating has a 50% chance of being THC and a 50% chance of being THF.  Overall, this means that 50% of the calves will be THC and 50% will be THF BUT you have to have a large enough sample size to see it come out like such.  If you flip a coin 100 times you will be closer to 50/50 than if you only flip it 10 times.  If you flip it 1000 times you will be closer to 50/50 than when you flipped it 100.  Sometimes we get lucky and sometimes we're unlucky.

 

[hamburgman]

Life is a bell curve and guess what that means outliers.  "Hot carriers" makes no sense sorry. 

As for winners being TH/PHA carriers.  It seems that many winners are a carriers in the market classes. How many clones of winners have been free of the defects?

 

[shorthornmn]

It seems to me from my experience at uw-madison that you are using simple mendelian genetics, the simple of all genetic forms. Many publications on th and pha that are presented to many producers and cattlemen. Mendelian genetics is almost like an over simplification of genetics and there are very few genes that work this way. The reason carriers are usually hairy and big boned is because the th and pha genes are located on the gene very closely to the genes for those traits- meaning that when DNA is inherited the genes are usually present together. Of course there are the double clean freaks that happen very rarely due to comlete chance of chromosomes lining up on the metaphase plate during meiosis and the anomaly of the slick double dirty calf. But back to more of the inheritance- often times genes aren't perfect as in the mendelian example most often presented. Even with large sample sizes the ratio for inheritance of the gene is never perfect. You also can not say with complete certainty there are not levels of "hottness" between bulls and cows and the passage of these genes because in fact there is just not enough testing on this. However a lot of breeders are starting to speculate this and I think this is the next step in the research on these defects (or at least it should be). One prime example that may support this "hottness" factor in the gene is from the Shorthorn bull Outkast. He often passed on the th gene however the th test couldn't pick it out even though it was the same. It was eventually traced back to him and the test was I believe altered so that it would pick up the "outkast" th gene.

 

[vet tech]

Life is a bell curve and guess what that means outliers.  "Hot carriers" makes no sense sorry. 

As for winners being TH/PHA carriers.  It seems that many winners are a carriers in the market classes. How many clones of winners have been free of the defects?

In terms of clubby bulls I see being promoted, none that I can think of

 

[KSUwildcat2009]

shorthornmn, Outkast doesn't really support the hotness theory.  You are right though, the "Outkast" mutation allele is a different mutation than the "Improver" allele.  The way that genetic testing works is you have to know what you are looking for.  Therefore, when Dr. Beever and BR didn't at first know what existed, they couldn't cater the test to look for both alleles.  So it doesn't change the fact that they existed, just says we weren't finding them yet.  If you search for "Outkast  Tibial Hemimelia" DL wrote an article that talks more about TH and PHA and she mentions the Outkast allele.