TH and phenotype

[itk]

I forgot to mention that I learned a way to identify carriers of TH this weekend and it had nothing to do with their legs but their head. When we unloaded cows Brain Kohlstaedt was able to tell which were THC and THF by looking at the bump that goes down the middle of their head that starts at the poll. He only missed one cow that tested THC that he called THF. He said if this bump goes down like four inches they are THC and if not they are THF. I don't know if there is any fact or science to back this up but in my isolated incident there was enough of a correlation for it to be more then just chance.

 

[Dusty]

Haven't heard that one yet...I usually just go by their pedigree and if they're good, they're a carrier.

 

[red]

Im noticed w/ my PHAC she had more of a short rounder head. Her full sister who is clean had a narrower head. Also the carrier is more steery looking.

Red

 

[knabe]

ok, we need pictures on this one as i don't have any carrier cattle, pha or th. 

the most cited phenotype for pha "in a positive" way, is upper and fore spring of rib.  hopefully this is due to another snp in the gene rather than the one that truncates the protein and is desirable in isolation from PHA.  justintime has a couple of cows with great spring of rib there, without pha.

remember, many genes are expressed in different tissues at different stages of development and will not always express in exactly the same quantity. 

starting poking around in the th gene and found that a translocation break point has been found in one human within an intron of a gene(i think it's the TH gene in human). introns are splice out, and the exons are used to transcribe and translate into protein.  i find this incredible, as crossover point is capable of occuring within a gene on the genomic scale.  i'm assuming this is not good.  if this were to occur a lot, this would indicate not much selective pressure.  i could be wrong, and crossovers occur all over the place with no protection mechanism within genes.  some people are studying this big time in corn with very powerful microscopes which look at stained chromosomes and known crossover points.  haven't kept up with this research in over 15 years.  in some respects, this is sort of a roundabout way of explaining why i think the pha gene is important, and that fullblood carriers may have some variation within the gene that may be beneficial in their PHAF allele and will be lost.  it's also why probably why paramount was considered inconsistent, in addition to the PHAC gene causing inconsistency in observed herds trying to use him on a variety of cows.  this is the only reason i would use a carrier, and i would find the "perfect" set of say 5 free cows and flush them all to at least 3 carriers i can think of, all full bloods, their names being paramount, universe 15, dalton.  telos and xxcc could think of some others under this scenario.  telos has not observed any carrier bulls out of i think dalton yet.  anyone know of one?  i remember thinking about this, but never had the info or the courage to just declare it.

 

[justintime]

I do agree that most TH carriers have this had shape that Brian Kolstaedt mentioned to you. I have noticed this as well, but I have seen a few animals that have fooled me. I had one female that had Improver 8 generations in the background of the pedigree that I was certain was clean as I could not see this ridge on her head. She turned out to be a carrier and is now a recip in my herd. As I have mentioned on here before, I really do not agree with people messing around with carriers in their breeding program, unless they are 100 % certain that no animal they produce that is a carrier will ever make it's way into a commercial operation... and that is very hard to do.

 

[farmboy]

if this is true, my market heifer is THC, and she has the phenotype to go with it, muscular and hairy

 

[kane1598]

I believe it.  I have had four Heatseeker steers over the years and all of them had that odd head and kept there hair all summer.  Coincidence?

 

[itk]

I believe this head thing is a better indication then leg set or hair. The frailest made, lightest muscled cow we sold Brain called a THC without hesitation because of the bump on her head and he was right.

 

[NHR]

I dont know about this bump thing. We had a TH Carrier cow (found out the hard way) and she did not have any bump on hear from the poll down.

 

[aj]

Are these real? I think the hair deal is for sure. Are the "bumps" reason to call a th calf a knot head? I think so. The shorthorn breed is on a slippery slope not to mention a bumpy road if the th deal is not controlled.

 

[red]

is that the same as the swirl of hair? It's supposed to show temperment.

Red

 

[CAB]

OK ITK, I'm like Knabe, we pics please, I spent time staring @ my possible carrier's last evening and again this morning, does the head need to be clipped to see this TH bump,line, whatever? I couldn't tell anything by looking @ mine, but this Brian dude could have saved everyone alot of time & money by sharing his TH test earlier.

 

[itk]

I will see if I can't find some pics or maybe JIT can help explain it alittle better since he seems to know what I am talking about. Brain said he was 100% accurate using this method to determine TH status on calves last fall when they were getting ready for their sale. I'm sure it is easier to detect if the head is clipped. By the way this Brain dude's  ;D family bred Boardwalk & Monopoly and were the original owners of Red Riders Drive with Dean's. He is well respected in the shorthorn breed so he is not some quack coming out of left field, there seems to be some truth to this method.

 

[CAB]

  No offence meant itk. I want to learn how to read the look. It may help alot of people. BTW, you didn't sell all of your cows, did you?

 

[aj]

There are TWO things that stick out to me. The fuller,rounder more plump head on the PHA carriers is also a factor. Whoops three things sticking out. Th carriers are hairy, straight legged, and more moderate framed. They can be attention getters in the ring and they are a real trophy. I guess th cattle will always have a place cause they are bodacious and really make the audience stand to attention. I would rather have the th test myself but this may be a cheaper method

 

[Jill]

Ok, I don't know that I agree with you, just felt all of the show heifers and I have 1 with a slick head.  I have 1 totally free with a big knot and 1 PHA with a big knot, but she is tested th free, maybe I am feeling something wrong, but I think I get what you' re talking about, it's like a big goose egg, never noticed it before.

 

[aj]

Maybe they could develop like a quick test they use for nitrates in feed. They could rub like a litmus paper on the calfs nose and it would turn purple  or something.I'd like to see more pictures too. Hope something is figured out. A guy could save jugs of money. ;D

 

[justintime]

Now that would be nice!  In my opinion, most carriers have some similar traits such as the ridge on their head, but I have also seen carriers that do not have this. Also carriers usually have more hair than non carriers, but occasionally some don't. When the test for TH  was developed, I already had an idea that I had used a carrier bull or two in the past. One of my current herd bulls at the time, was a double bred Improver, but I thought he was clean as he was smooth headed, had fairly short hair, and had been used on numerous females that carried the bloodlines of another bull who I felt was a carrier.
I was surprised when I got my TH test results and found out that this bull was a carrier. He certainly didn't fit the profile I thought carriers had. I only have a few daughters left in my herd from this bull and there are only two carriers in the group. Both are now excellent recips and they will remain recips.

 

[garybob]

I think that all of this talk about the "physical traits" of carriers is off the wall. This thinking reminds me of the false beliefs of some breeders that erroneously believe that Show Steers(and their Sisters, who, in turn, pass this crap onto following generations of offspring) MUST be carriers, in order to be competetive.Telling customers that there is a direct  link between phenotype and defect status, IMVHO, is only a way for the owners of Dirty Bulls to get people to buy their Semen & Breeding Stock.

By now, with all of this testing that has already been done, there should be "clean offspring a-plenty" of original "genetically and economically valuable"carrier animals. The Test Dr Beevers invented IMHO, was INTENDED to ELIMINATE the gene and its' negative effects (wasted investment money, heart-broken kids, and the continued, unjustified, lack of confidence from the commercial industry in a very valuable breed) from a breeding population. All We've done, thus far, is MAKE MORE CARRIERS.

Does this make sense?

GB

 

[aj]

Does it make sense to have breast enlargements? Does it make sense to have glamour photos taken of yourself? Does it make sense to take steroids. The show world is a beauty contest. My goal is to have a defect free herd. I have people showing up and skimming the top off the heifer calves before I can get them tested. They are always th carriers. I don't have a lot of it. I am putting 25 heifer calves back into my herd and all but 2 are th free. I had like 6 sell before I could get them tested and they all came up th positive latter on. There is a look to them. The buyers knew about the possibilities. I know a guy who tested every female in his herd(shorthorn...we'll call him marty) He hauled every th carrier to the salebarn. This takes guts and I admire that. It is a difficult situation.If it ever bleeds over into the commercial industry it is goig to be a nightmare.