|
Post by cascade on May 31, 2017 17:08:57 GMT
Horn Genetics 101 Both dehorned and polled cattle are genetically horned. A complex set of genes code for horns... There are genes that control length of horns and genes that control thickness of horns and genes that control angle of horns and genes that control color of horns and genes that control curvature of horns. Both polled and dehorned cattle have all these horn genetics. The polled gene is a simple on/off genetic switch that when flipped to "off" simply interferes with the growth of horns, much in the same way a hot iron interferes with the growth of horns. But the horn genetics are still there. All Dexters including horned, dehorned, and polled Dexters are genetically horned. This horned girl (Cascade's Spur) is 4 years old in this picture. She has two polled parents and 4 polled grandparents (including some homozygous-polled grandparents), who contributed their horn genetics to her. She perfectly meets the 1900 Dexter Breed standard and so do all of her offspring when she is bred on a similar bull. I
|
|
|
Post by Donlin Stud on Jun 1, 2017 0:34:28 GMT
Horn Genetics 101 Both dehorned and polled cattle are genetically horned. A complex set of genes code for horns... There are genes that control length of horns and genes that control thickness of horns and genes that control angle of horns and genes that control color of horns and genes that control curvature of horns. Both polled and dehorned cattle have all these horn genetics. The polled gene is a simple on/off genetic switch that when flipped to "off" simply interferes with the growth of horns, much in the same way a hot iron interferes with the growth of horns. But the horn genetics are still there. Cascade, Cascade, Cascade: Just because you want it to be so……doesn’t make it so ! Heard the saying: Walks like a duck, talks like a duck……………….. A mutation _is_ a mutation A mutation is an error in the DNA sequencing or a 'mess-up' within the chromosome (multiple genes). There’s no ‘switch’ turning on or off. Naughty of you
|
|
|
Post by cascade on Jun 1, 2017 1:09:04 GMT
I've studied genetics pretty thoroughly and I can tell you that a relatively small amount of DNA actually codes for things like muscle and cartilage and bones and hair, and horns, while a lot of DNA codes for switches, to simply switch on or off certain features. For example, chickens still have genes for teeth, but they are switched off. Polled Cattle have genes for horns, but a switch has shut the horn growth off. The genes that code for things like hair color involve the production of proteins and those genes are easier to find and study... But the genes that are simple switches, turning things on or off, are harder to find and study. So far, they haven't been able to pinpoint the "polled" gene, because it's likely just one of these switches. Here's an article and a nice short video that will help explain genetic switches to you. opb.pbslearningmedia.org/resource/novat10.sci.life.evo.fruitfly/switching-genes-on-and-off/#.WS9iu8plDqA
|
|
|
Post by jamshundred on Jun 1, 2017 15:19:57 GMT
It doesn't matter. None of that scientific mumbo-jumbo explains the drastic changes in the phenotype as switches . . switching.
The heritage horned Dexter breed is being changed beyond recogniton and only those of us working to insure there is a population of original phenotype Dexters are doing a single thing to stop the widespread destruction. It is those like YOU who are responsible and who make-up all this mumbo-jumbo to cover up your participation in the effort to turn a unique breed with a set of characteristics found in no other breed. . . . . into the COMMON PLACE generic animals that can be found anywhere and everywhere and are nothing special at all.
Nothing you do or say will change the fact that history will record you not as a founder of a new breed ( which it should have) but as a culprit in the destruction of an old one.
|
|
|
Post by cascade on Jun 1, 2017 21:51:23 GMT
I support folks who are trying to follow every word of the old original phenotype as written in the first standard published in 1900.
That means:
100% short and very beefy frames NO brown/dun (only red or black allowed) NO long legs NO animals over 900 pounds. NO dehorning NO upright horns (horns should sweep mostly forward and only slightly upward) NO Testicle removal (it doesn't say it's ok to remove testicles)
I haven't found ANYONE who is completely following every word of that first official standard.
|
|
|
Post by Donlin Stud on Jun 1, 2017 22:34:50 GMT
...... to cover up your participation in the effort to turn a unique breed with a set of characteristics found in no other breed. . . . . into the COMMON PLACE generic animals that can be found anywhere and everywhere and are nothing special at all. Judy, that is brilliant (the above) In just a couple of lines, you have bundled the sole reason WHY traditional bloodlines are so very important, and WHY the Dexter breed needs 'guardians of traditional bloodlines like most of the members here on this forum.' Your writing " the COMMON PLACE generic animals that can be found anywhere and everywhere and are nothing special at all." really brings it all home.
|
|
|
Post by Donlin Stud on Jun 1, 2017 22:49:21 GMT
That means: NO brown/dun (only red or black allowed) NO long legs Cascade yes I agree with most of what you wrote BUT.... Just because there is no mention of the Dun colour doesnt mean its a "shouldn't be any" approachThe advancement in DNA sequencing and such tells us that the Dun colour has had to be there all along.It cant just suddenly appear - NOT when its DNA is UNIQUE to the Dexter breed. We have all spoken about it - there has been much research and discoveries that due to the gap in time, is hard to prove 100% as we cant ask those breeders of the 1900 about colour. And as for NO long legs - well again, you have taken a few words out of context. Those born with "long legs" were registered as Kerry Cattle. Kerry and Dexters were determined by those breeders in the 1900s plus to be similar breeds of cattle but not the same breed So again, with the now understanding of DNA we all know the long legs and the short legs are the same breed being the Dexter.
|
|
|
Post by cascade on Jun 2, 2017 0:04:11 GMT
1. What we call "dun" is a mutation that frequently pops up in birds and mammals. A good working copy of the TYRP1 gene produces a protein/enzyme called TYrosinase Related Protein 1 which is required to make black pigment look black... An animal needs at least one good working copy of TYRP1 to keep black pigment from fading to brown. Two broken copies of TYRP1 results in black pigment fading to brownish from the lack of the tyrp1 enzyme. That broken gene is usually referred to as "brown" in most animals, although it's called "chocolate" in lab dogs. It likely was a fresh mutation in Dexters in perhaps the 1920's or 1930's. We can ask the 1900 breeders about color. They wrote it in the breed standard... Black or Red ONLY. We know they had some almost pure white Dexters back then, but they weren't standard so breeders would have been expected to select away from non-standard colors. If you accept the brown mutation in Dexters with no absolute proof of its source, then you can accept the polled mutation in Dexters. 2. Dexters aren't short-legged Kerry... There was a brief time when Kerry and Dexter-Kerry were two types of Kerry, but when they invented the isolated True Dexter breed they brought in lots of shorter-legged beefy animals like the Devon and Short-horn and others to mix in to start the new beef-framed Dexter breed with shorter legs as most beef-framed animals had. The 1900 Breed Standard very clearly describes a beef-framed breed with 100% short thick beefy legs. 3. Wee Gaelic Ms. Fermoy is a "Legacy" Dexter. Most red polled Dexters descend from her and get their looks from her. Is her phenotype special and traditional or not?
|
|
|
Post by lonecowhand on Jun 2, 2017 19:57:32 GMT
Oh, we're back to it's being a polled mutation. Your historical viewpoint goes from "It Might Be" in one post, to a jump to: "It Was", as though you were there. I'd stick to "it might be" if credibility were important to you.
You might also include "NO Wings" in your list!
|
|
|
Post by cascade on Jun 3, 2017 0:26:17 GMT
BD1 and BD2 Chondrodysplasia genes are either fresh mutations in Dexters, or they snuck in from other breeds.
Dun gene is either a fresh mutation in Dexters, or it snuck in from other breeds.
Polled gene is either a fresh mutation in Dexters, or it snuck in from other breeds.
We will never know for sure.
|
|
|
Post by jamshundred on Jun 3, 2017 11:34:55 GMT
Dexter cattle are a breed of DWARF cattle. The photos and data from the founding of the breed substantiate this and Lady Loder identified her herd as being a herd of DWARF cattle.
Polled did not "snuck in" to Dexters on a mutation. It was introgressed. In the case of US Dexters, nearly all descend from ONE bull. The Polled Dexters in the US, ( which are NOT really Dexters at all since Dexters are a horned breed, and just like the White Dexters, polled Dexters should have been given a new and separate identity but those involved wanted to trade on the historical foundation of the original bloodlines).
|
|
|
Post by jamshundred on Jun 3, 2017 11:39:47 GMT
PS Kirk. You have a FB page. Why don't you post your theories there and conduct your conversations on the world stage where you might have lots of "likes" and dialogue. WHY are you here? None of us are buying into your SPIN.
The psychology of your constant needy effort is worthy of a government research grant.
|
|
|
Post by cascade on Jun 4, 2017 0:25:56 GMT
I post anywhere I can to set the record straight about the true facts of the Dexter breed and to correct all the misinformation.
Both the first description of Dexters (by Professor Low in 1840's) and the first official breed standard (published in 1900) describe Dexters as having a typical thick beef frame with short legs and thick beefy builds. Those descriptions described a breed with one single phenotype. Neither of those descriptions mentioned anything at all about the three different phenotypes you get with BullDog-type Chondrodysplasia. So clearly, Dexters weren't meant to be based on chondrodysplasia. Dexters were clearly meant to be a breed of true-breeding short and beefy cattle of one single short and thick body-type (and a milkable udder).
Most all breeds that select for shorter phenotypes are plagued with unwanted dwarfism defect genes popping up. When Angus and Herefords were selecting for shorter animals in the 1930's to 1960's, they too were plagued by dwarfism. When you select for shorter animals, you have to be careful not to select an animal with a genetic bone disease which can cause that shortness. You want to select for natural, healthy shortness.
Back to horns, Professor Low's description didn't even mention horns, so perhaps he saw polled Dexters or dehorned Dexters, or the horns were so unimportant to Dexters that he just omitted describing them.
The 1900 Breed Standard briefly mentions horns, and the breed standard could have specifically banned interfering with the growth of horns, but they failed to do so. They left that decision up to breeders.
|
|
|
Post by Donlin Stud on Jun 4, 2017 21:56:24 GMT
I post anywhere I can to set the record straight about the true facts of the Dexter breed and to correct all the misinformation. Your interpretation of " the true facts of the Dexter breed and to correct all the misinformation" is purely in the eyes of the beholder..........
|
|
|
Post by cascade on Jun 5, 2017 6:19:46 GMT
Read Professor Low's 184O's description of Dexters and you'll see nothing about horns and nothing about the three different phenotypes associated with BD-Chondrodysplasia. That's 100% fact.
|
|
|
Post by lakeportfarms on Jun 5, 2017 17:36:40 GMT
Read Professor Low's 184O's description of Dexters and you'll see nothing about horns and nothing about the three different phenotypes associated with BD-Chondrodysplasia. That's 100% fact. Fortunately, we have photos from over a century ago. I've yet to see a photo from that time period that shows a polled animal identified as a Dexter. I have however seen many photos that show what are clearly dwarf Dexters. And given that up until just a short number of years ago there were 4 different colors of Dexters on the ADCA website (Black, Red, Dun, Red/Dun) who is to say that Dun dexters weren't mistaken for red, or even considered as variations of red. I've had some dun ones here myself that are difficult to determine their color during certain stages of their growth. You clearly subscribe to the philosophy that if you repeat it often enough, people will accept it as fact. You may convince some people who just drink the grape Kool Aid, but not those of us with a more rational and critical mind.
|
|
|
Post by lakeportfarms on Jun 6, 2017 11:32:27 GMT
Kirk, if the polled gene is simply an "on/off" switch and doesn't affect anything else, please explain why when breeding two polled goats together there is a high chance of having hermaphrodite kids. Clearly the polled status affects other genes. In the case of the goat, it affects the sex genes.
Who knows exactly what is affected with the cattle polled gene? I've seen a lot of reports that it affects the sheath attachment of bulls, for example. I wonder what else is affected?
|
|
|
Post by cascade on Jun 6, 2017 14:30:22 GMT
1. No records were kept concerning horn status of Dexters until at least the 1980's. Even today we still don't completely track the horn status of Dexters.. The Old Orchard herd was a hornless herd, but the pedigree records say "Horned"
2. Fewer than 3% of Dexters were photographed prior to 1910. Photographers liked to photograph freaks, so photographs don't paint a true picture.
3. The written standard of 1900 clearly tells us what they expected Dexters to be, regardless of the fact that many Dexters didn't meet that standard. The written standard tells us that Dexters should be only red or black. They could have said brown too, but they didn't. The written records tell us there was a foundation cow named Lily who was pure white with some red flecking... She was likely either a short-horn, or an Irish Moiled (Polled) cow. But she didn't meet the standard, so they would have been expected to breed away from that.
4. Concerning dun, we Dexter breeders treat dun in a very confused manner. Sometimes we refer to dun as a phenotype color, and sometimes we refer to dun as a genotype status, ignoring the actual color. The Dun gene is referred to as the Brown gene in general genetics, that's why the genetic testing uses the letter "b" as a code for it.
5. The 1900 standard said red or black only, they clearly were referring to phenotype (what the animal looked like) and not genotype. The Irish clearly understood the difference between black hair, red hair, and brown hair. They clearly expected Dexters to be red or black but not brown... Yes, some Dexters may have had the brown (dun) gene, but if they had enough red pigment, they could have met the standard for being red. But clearly, brown colored Dexters were not acceptable.
6. Many British breeds including Angus and Herefords went through phases of selecting for short-legged, short animals. The photos of the show winners from the 1940's and 1950's show lots of very short legged beefy frames. Whenever you select for short beefy frames, there's a chance of dwarfism defects slipping in. The Angus and hereford people figured it out and culled the defective ones.
7. It's very difficult to tell from photos which animals have dwarfism defects including lethal genes and which animals just have short genetics. Clearly, the 1900 standard calls for Dexters to have one single body type, of naturally true-breeding short and beefy genetics.
8. In various species of animals, different conditions can affect horn growth. Some of those conditions are simple switches in some species, while in other species, hornlessness can be caused by defects. In the case of sheep and cattle, there are some simple switches that shut horn growth off, but in the case of goats, there is a defect that causes hornlessness and associated fertility issues. In Icelandic sheep, the polled gene is quite common, due to the genetic switch for horns getting turned off. Other than horns, there is no difference between the polled and horned Icelandic sheep (I've bred hundreds of them). In sheep, two horned animals can have a polled lamb.
|
|
|
Post by jamshundred on Jun 6, 2017 15:52:02 GMT
This is the problem Kirk. YOU spin the truth. That is NOT acceptable. Truth is like pregnancy. You can't be a little bit of either.
When you say the Old Orchard herd was hornless. . . . . . you know very well they were horned cattle that the owner dehorned. You are attempting to provide a different status to those who are not experienced. I abhor anyone who is dishonest and attempts to mislead me or others. . .. . . . and I see far too much of that today. When any media source is not trustworthy it taints all media sources with the same brush. You also give only half of the facts. The half that supports the contention you are offering.
|
|
|
Post by lonecowhand on Jun 6, 2017 17:04:33 GMT
Keep in mind that introgression of polledness through sexual means has the possibility of adding all sorts of other traits, not just hornlessness. This is not gene splicing.
The more incidence of the same donor in the pedigree further selects TOWARD those alien genes, effectively selecting away from the Dexterness.
The Title and Whole Theme of this thread is absurd: By anyone's but your mind, Polled is not Horned, Sorry...
|
|
|
Post by cascade on Jun 7, 2017 3:52:33 GMT
1. DNA tests tell us Saltaire Platinum is likely pure Dexter at least 5 generations back.
2. Dexters didn't start out as a pure breed on some isolated island... Instead,they started as a mishmash of tons of other breeds in an area and relatively recent time in Ireland when there were scores of other breeds coming and going and intermixing. The foundation Dexters weren't even Dexters.
3. All Dexters have some relatively recent introgressions because sneaker bulls travel and pedigrees were full of errors until full DNA parentage testing was started fairly recently. Also, many Dexter breeders in the past also had non-Dexter bulls on their farms... The Peerless Dexter herd also kept countless short-horn bulls on their place, and you can bet they sometimes mixed with the Dexters.
4. The title of this thread is perfectly accurate. Many people who don't understand genetics believe there is either a polled gene, or a horn gene in Dexters.. But that is wrong. All Dexters including polled Dexters have horn genes, and the horn growth initiation switch is either turned on, or turned off. If I turn the light switches off in my house, it's still wired for electric lights. Polled Dexters still have the genetics for horns, but they are switched off. You can also use heat or chemicals to switch horn growth off.
|
|
|
Post by lakeportfarms on Jun 7, 2017 11:04:14 GMT
Cascade, I don't think that the cow that you post at the beginning of this thread is representative of most of the descendants of Platinum. If it is representative of what you are aiming for in your own herd, rather than talking so much at people you may want to do a little listening. Ask some long time breeders that you respect for their honest evaluation of her.
|
|
|
Post by lakeportfarms on Jun 7, 2017 12:19:04 GMT
Cascade, I don't think that the cow that you post at the beginning of this thread is representative of most of the descendants of Platinum. If it is representative of what you are aiming for in your own herd, rather than talking so much at people you may want to do a little listening. Ask some long time breeders that you respect for their honest evaluation of her.
|
|
|
Post by cascade on Jun 7, 2017 13:25:40 GMT
Here is a direct daughter of Saltaire Platinum
|
|
|
Post by Donlin Stud on Jun 7, 2017 22:05:13 GMT
1. DNA tests tell us Saltaire Platinum is likely pure Dexter at least 5 generations back. Im glad to see that you are now using the word "likely" and "5 generations back" That is certainly more representative of the wording used by UC for such results from such a test.
|
|
|
Post by lakeportfarms on Jun 8, 2017 10:50:10 GMT
What I am saying Cascade is that your cow in the first post does not look like a Dexter of 1900, even if the photo was in black and white. Put on your knickers, bow tie, beanie hat, and then take another black and white photo of you and that cow, and put it side by side with the Dexter cow "LaMancha Love Lost", and look closely. There is no comparison. Over 100 years later and you're going backwards with the breed.
If you would like to see the photo, go to Judy's "Dexter Cattle Historical" site on Facebook and look at the cover photo. I don't think she's blocked you from that page, but if she has, just log on as "Al Nichols" and you can probably get in. Just be respectful and don't spoil that page, OK?
|
|
|
Post by jamshundred on Jun 8, 2017 22:29:31 GMT
LOL. I don't block. Your comment brings a thought I've had on a number of occasions. There are those in this breed who claim they are passionate about Dexters. And some who portray an interest in historical content. ( One of them I mentored by sharing EVERY SINGLE piece of historical data I had including books). Yet. . . . they are really nothing but political hacks and self-serving egotists and closet Legacy registry researchers. You never see them post on the historical information on the Dexter historical site. Their rhetoric is phoney baloney.
|
|
|
Post by jamshundred on Jun 8, 2017 22:31:31 GMT
Kirk,
On that photo of the direct daughter of SP you posted. Would you have culled or bred her were she in your herd?
|
|
|
Post by cascade on Jun 9, 2017 4:07:32 GMT
If the black horned direct daughter of Saltaire Platinum (pictured above) was born on my farm, and if her health and behavior was exceptional, I would have kept her and bred from her... Or I would have found a horn-loving home for her.
I totally understand people loving horns, ...my one horned Dexter(out of 70 polled Dexters) is kinda special to me, I'd have a hard time parting with her. I'd NEVER dehorn/disbud a calf born on my farm.
I only have a problem when someone who burns horns off the head of a calf, argues that their animal is more "traditional" than a calf born naturally without horns.
When someone markets a "traditionally horned" Dexter that's had its horns removed, it seems dishonest and harmful to the cause of promoting horned Dexters...
Likewise, when someone who is proud of their traditional horned herd is told that their animals can't be traditional because one great great great great great great grandparent was polled... That's very harmful to the cause of promoting horned Dexters.
There is only one argument that can't be easily disputed.... A Dexter that actually has horns is more traditional than a Dexter that doesn't have horns.
|
|
|
Post by Donlin Stud on Jun 13, 2017 22:09:27 GMT
I only have a problem when someone who burns horns off the head of a calf, I have the same problem
|
|