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Pavonne CamererTraditionally Horned Dexter Cattle
June 23 at 3:56pm ·
This is copied from the UC Davis website:
Pavonne Camerer This article talks about a mutation in horned dexter cattle that results in polled offspring.
June 23 at 4:53pm ·
Vicki Solomon Thank you for this good info. Upon careful reading, I found the article does not say that a mutation in a Dexter necessarily occurred. The article says that there are two distinct polled genes from different sources, one from Freisian/Jersey strains and one from celtic strains, and that they can be distinguished from one another through the UC Davis tests. It does not say that a mutation in a Dexter necessarily occurred.
June 24 at 11:58am ·
Pavonne Camerer Thank you for your comment. I have read the article several times and still may not understand it. Is it possible for a heterozygous polled dexter be created if a horned animal carries the mutation? Or is it totally impossible for a polled dexter to have ever been born of horned animals (i.e. no such mutation possible?)? I would appreciate some help understanding this. I looked at the origin of the polled dexter cow that started the polled line, and she was out of horned parents.
June 24 at 2:32pm
Patti Adams Pavonne Camerer - a horned Dexter cannot "carry" the polled gene. The polled gene is dominant, so if it is present, it is expressed and the animal does not grow horns (though it may grow scurs, because these are controlled by a different gene pair on a different chromosome). In order for a Dexter to be polled and to come from two horned parents, one of the genes that codes for horns would have to have been damaged (mutated) in either the egg or in the sperm, prior to conception of the calf. If the Dexter calf inherited a mutated (damaged) horn gene and a normal horn gene, it would not be able to grow horns since it needs two normal functioning horn genes, in the gene pair on Chromosome 1, in order to code for and grow horns. The polled gene is just a damaged (mutated) horn gene that doesn't code properly for horn growth. The test done at UC-Davis distinguishes between two different, known polled mutations (damaged horn genes) and the normal horn gene, located on Chromosome 1.
June 24 at 3:30pm · Like · 3
Patti Adams Pedigree records can have errors (i.e. wrong sire or wrong dam). If either the sire or the dam of record are not correct (and one of them is polled) then there is the opportunity for the polled gene to be introduced accidently. In the case of Godstone Esmeralda (the granddam of Saltaire Platinum), she was one of three black heifers, all born on the Godstone Farm during the same week in May 1984. Godstone Esmeralda's dam of record is given in the DCS pedigree registry as Broadridge Dawn, DCS F09211 a black, horned Dexter cow born in 1977. But there was an Appendix B, black, polled Dexter cow, Finney Jubilee, DCS B182, also born in 1977, that also had a black heifer calf that same week in May 1984, also sired by Woodmagic Pine Martin, and also born on the Godstone Farm. Finney Jubilee's heifer calf was registered as Godstone Emily, DCS C242, black and horned. So there exists a possibility that the two black heifer calves may either have been switched by the cows, or mis-identified by the herdsman, and that's how a polled heifer could end up being registered as being out of a horned sire and a horned dam. If this actually happened (and it is just speculation, at this point) then the polled gene in Godstone Esmeralda may have come from Finney Jubilee, who inherited it from her polled dam, Vycanny Orphan Annie, DCS A239. Orphan Annie was AI-sired by a registered, polled Dairy Shorthorn bull, Swinsongrange Challenger (Herd Book Number 0222549). Can't prove it at this point in history, but it is a more probable scenario than having a new polled mutation suddenly occur in either the sperm or the egg, prior to conception of the calf.
June 24 at 4:50pm · Edited
Pavonne Camerer Patti, thank you for the in depth and helpful explanation. The ADCA should include your well written explanation on the website for members to understand the history of the polled lines. Will the DNA testing on the SP semen solve any of the mystery of the origin of polled dexters?
June 24 at 6:21pm ·
Patti Adams Pavonne Camerer - We will see what it can tell us. The breed specific test done at UC-Davis is considered valid within a 5-generation pedigree, so it may not find the specific markers for Shorthorn, since those are further back in the pedigree, beyond the 5th generation (if Godstone Esmeralda is the daughter of Finney Jubilee). But there is a chance, that some of the Shorthorn specific markers will show up and that would be supporting (but not definitive) evidence of the scenario where the heifer calves had been accidently switched or mis-identified, prior to registration with the DCS. I'm only an ADCA member, not staff, nor Board, nor committee member, so this is only a plausible explanation for how Godstone Esmeralda ended up being heterozygous polled, it is purely speculation at this point. If the breed specific marker test done at UC-Davis comes up with more evidence to support this scenario, then it may go further. However, until then, the only record that the ADCA can rely on, is the pedigree record in the Dexter Cattle Society registry, that is the originating and "official" pedigree of Godstone Esmeralda and her grandson, Saltaire Platinum.
June 24 at 8:09pm · Edited ·
Pavonne Camerer Patti, what happens if the DNA test reveals genetics from non dexter cattle? Polled dexters are firmly set within the association . Do you think the ADCA would initiate a distinction in registrations for "modern dexters" and traditional horned dexters? I think the traditional horned dexters are wonderful, and I applaud everyone who is part of the movement to preserve them, to educate dexter owners on the history, and promote them. However, I like the polled dexters too and hope that both polled and horned can be promoted through the ADCA. Thank you again for your posts. I am learning a lot from this website.
June 24 at 8:58pm ·
Patti Adams Pavonne Camerer - I don't know what the ADCA will do with the test result information. I guess we could turn the question around and ask, what will the traditional Dexter breeders expect the ADCA to do if the UC-Davis VGL breed specific test doesn't find any "other breed" markers in Saltaire Platinum's marker profile (other than the polled gene)?
June 24 at 9:15pm ·
Pavonne Camerer It is all very interesting. When do you expect the results to be in?
June 25 at 10:44am ·
Vicki Solomon I sure apprciate your knowledge and your links, Patti Adams. I am trying to learn all I can.
June 25 at 11:27am
Craig Turpin Pavonne - At the Annual General Meeting (AGM) for the ADCA, Dr. Philip Sponenberg from the u
7 hrs ·
Craig Turpin oops, hit enter. .. From the U of Virginia and the Livestock Conservancy stated that the polled gene in Dexters could have ONLY come from another breed (as the chances of the exact same gene mutating in the exact same way was infinitesimally small). Truth of the matter is that there never was any reaason to believe otherwise given SP pedigree issues. This is issue should be regarded as "resolved" once and for all: The polled gene was introduced by another breed. (If you don't mind having a Dexter that is less than 1% of some other breed, and don't want horns, go polled. If you want to preserve the original Dexter genetics, then stick to pedigrees with no ungraded/outcrossed/appendix pedigrees.)
7 hrs ·
Judy Sponaugle Darn, if transformations aren't interesting to behold! The herd record of the Godstone herd, showing all the animals and their calves and the issue with the ear marks has been on my personal website for a at best a couple years shy of a decade! The progeny records of Godstone Esmeralda and their progeny which disproved the deceit used in this country to substantiate the novel mutation have been there as well. The odds in the millions of this being a novel mutation were published in the 90s in a publication by the DCS. Just ONE year ago, ADCA commissioned Patti Adams to write a white-wash article about Godstone Esmeralda that was published in the Bulletin which said nothing of the truth of the situation or what she just posted here, this information/musing having been available in writing by Dr. Duncan MacIntyre for a number of years. One must wonder why the change in tune in just a year. DNA is the reason. You can challenge and discredit common sense, but not DNA.
Pavonne CamererTraditionally Horned Dexter Cattle
June 23 at 3:56pm ·
This is copied from the UC Davis website:
Polled vs Horned
Introduction
From the time when livestock was first domesticated, modifications to the wild types have been selected both for animal husbandry and aesthetic reasons. Unique and large horns define cattle breeds such as Texas Longhorn, Highland Cattle and Ankole Watusi. However, in modern times many cattle are maintained in more crowded conditions such as barns and small fenced pastures where polled phenotypes are more desirable for both beef and dairy breeds.
Recently, candidate mutations associated with polled phenotype in European breeds of cattle were found. There are 2 independent origins of polled, one found in Holstein-Friesian and Jersey breeds (Pf), the other in many European breeds of Celtic origin (Pc) such as Angus, Blonde d’Aquitaine, Dexter, Limousin, Charolais, and Hereford, among others. Polledness is dominant; a polled animal can have one or two copies of the gene. All offspring of a bull with 2 copies of polled (homozygous) will be polled. Genetic testing is a cost-effective means to determine if a polled animal has 1 or 2 copies of the gene.
The Veterinary Genetics Laboratory offers a test for the polled gene to assist breeders in selecting cattle that have 2 copies of Polled gene.
ORDER TEST | PRICE LIST
Allow 2-6 business days for results.
Results reported as:
H/H HORNED. No copies of either Polled molecular marker are present.
Pf/H POLLED. One copy of the Polled-Friesian molecular marker is present. At least 50% of the offspring will be polled.
Pf/Pf POLLED. Two copies of the Polled-Friesian molecular marker are present. All offspring will be polled.
Pc/H POLLED. One copy of the Polled-Celtic molecular marker is present. At least 50% of the offspring will be polled.
Pc/Pc POLLED. Two copies of the Polled-Celtic molecular marker are present. All offspring will be polled.
Pc/Pf POLLED. One copy of Polled-Celtic and 1 copy of Polled-Friesian molecular markers are present. All offspring will be polled.
Reference:
Medugorac I, D Seichter, A Graf et al. Bovine Polledness – An autosomal dominant trait with allelic heterogeneity. PLoS One 7(6): e39477, 2012
Introduction
From the time when livestock was first domesticated, modifications to the wild types have been selected both for animal husbandry and aesthetic reasons. Unique and large horns define cattle breeds such as Texas Longhorn, Highland Cattle and Ankole Watusi. However, in modern times many cattle are maintained in more crowded conditions such as barns and small fenced pastures where polled phenotypes are more desirable for both beef and dairy breeds.
Recently, candidate mutations associated with polled phenotype in European breeds of cattle were found. There are 2 independent origins of polled, one found in Holstein-Friesian and Jersey breeds (Pf), the other in many European breeds of Celtic origin (Pc) such as Angus, Blonde d’Aquitaine, Dexter, Limousin, Charolais, and Hereford, among others. Polledness is dominant; a polled animal can have one or two copies of the gene. All offspring of a bull with 2 copies of polled (homozygous) will be polled. Genetic testing is a cost-effective means to determine if a polled animal has 1 or 2 copies of the gene.
The Veterinary Genetics Laboratory offers a test for the polled gene to assist breeders in selecting cattle that have 2 copies of Polled gene.
ORDER TEST | PRICE LIST
Allow 2-6 business days for results.
Results reported as:
H/H HORNED. No copies of either Polled molecular marker are present.
Pf/H POLLED. One copy of the Polled-Friesian molecular marker is present. At least 50% of the offspring will be polled.
Pf/Pf POLLED. Two copies of the Polled-Friesian molecular marker are present. All offspring will be polled.
Pc/H POLLED. One copy of the Polled-Celtic molecular marker is present. At least 50% of the offspring will be polled.
Pc/Pc POLLED. Two copies of the Polled-Celtic molecular marker are present. All offspring will be polled.
Pc/Pf POLLED. One copy of Polled-Celtic and 1 copy of Polled-Friesian molecular markers are present. All offspring will be polled.
Reference:
Medugorac I, D Seichter, A Graf et al. Bovine Polledness – An autosomal dominant trait with allelic heterogeneity. PLoS One 7(6): e39477, 2012
Pavonne Camerer This article talks about a mutation in horned dexter cattle that results in polled offspring.
June 23 at 4:53pm ·
Vicki Solomon Thank you for this good info. Upon careful reading, I found the article does not say that a mutation in a Dexter necessarily occurred. The article says that there are two distinct polled genes from different sources, one from Freisian/Jersey strains and one from celtic strains, and that they can be distinguished from one another through the UC Davis tests. It does not say that a mutation in a Dexter necessarily occurred.
June 24 at 11:58am ·
Pavonne Camerer Thank you for your comment. I have read the article several times and still may not understand it. Is it possible for a heterozygous polled dexter be created if a horned animal carries the mutation? Or is it totally impossible for a polled dexter to have ever been born of horned animals (i.e. no such mutation possible?)? I would appreciate some help understanding this. I looked at the origin of the polled dexter cow that started the polled line, and she was out of horned parents.
June 24 at 2:32pm
Patti Adams Pavonne Camerer - a horned Dexter cannot "carry" the polled gene. The polled gene is dominant, so if it is present, it is expressed and the animal does not grow horns (though it may grow scurs, because these are controlled by a different gene pair on a different chromosome). In order for a Dexter to be polled and to come from two horned parents, one of the genes that codes for horns would have to have been damaged (mutated) in either the egg or in the sperm, prior to conception of the calf. If the Dexter calf inherited a mutated (damaged) horn gene and a normal horn gene, it would not be able to grow horns since it needs two normal functioning horn genes, in the gene pair on Chromosome 1, in order to code for and grow horns. The polled gene is just a damaged (mutated) horn gene that doesn't code properly for horn growth. The test done at UC-Davis distinguishes between two different, known polled mutations (damaged horn genes) and the normal horn gene, located on Chromosome 1.
June 24 at 3:30pm · Like · 3
Patti Adams Pedigree records can have errors (i.e. wrong sire or wrong dam). If either the sire or the dam of record are not correct (and one of them is polled) then there is the opportunity for the polled gene to be introduced accidently. In the case of Godstone Esmeralda (the granddam of Saltaire Platinum), she was one of three black heifers, all born on the Godstone Farm during the same week in May 1984. Godstone Esmeralda's dam of record is given in the DCS pedigree registry as Broadridge Dawn, DCS F09211 a black, horned Dexter cow born in 1977. But there was an Appendix B, black, polled Dexter cow, Finney Jubilee, DCS B182, also born in 1977, that also had a black heifer calf that same week in May 1984, also sired by Woodmagic Pine Martin, and also born on the Godstone Farm. Finney Jubilee's heifer calf was registered as Godstone Emily, DCS C242, black and horned. So there exists a possibility that the two black heifer calves may either have been switched by the cows, or mis-identified by the herdsman, and that's how a polled heifer could end up being registered as being out of a horned sire and a horned dam. If this actually happened (and it is just speculation, at this point) then the polled gene in Godstone Esmeralda may have come from Finney Jubilee, who inherited it from her polled dam, Vycanny Orphan Annie, DCS A239. Orphan Annie was AI-sired by a registered, polled Dairy Shorthorn bull, Swinsongrange Challenger (Herd Book Number 0222549). Can't prove it at this point in history, but it is a more probable scenario than having a new polled mutation suddenly occur in either the sperm or the egg, prior to conception of the calf.
June 24 at 4:50pm · Edited
Pavonne Camerer Patti, thank you for the in depth and helpful explanation. The ADCA should include your well written explanation on the website for members to understand the history of the polled lines. Will the DNA testing on the SP semen solve any of the mystery of the origin of polled dexters?
June 24 at 6:21pm ·
Patti Adams Pavonne Camerer - We will see what it can tell us. The breed specific test done at UC-Davis is considered valid within a 5-generation pedigree, so it may not find the specific markers for Shorthorn, since those are further back in the pedigree, beyond the 5th generation (if Godstone Esmeralda is the daughter of Finney Jubilee). But there is a chance, that some of the Shorthorn specific markers will show up and that would be supporting (but not definitive) evidence of the scenario where the heifer calves had been accidently switched or mis-identified, prior to registration with the DCS. I'm only an ADCA member, not staff, nor Board, nor committee member, so this is only a plausible explanation for how Godstone Esmeralda ended up being heterozygous polled, it is purely speculation at this point. If the breed specific marker test done at UC-Davis comes up with more evidence to support this scenario, then it may go further. However, until then, the only record that the ADCA can rely on, is the pedigree record in the Dexter Cattle Society registry, that is the originating and "official" pedigree of Godstone Esmeralda and her grandson, Saltaire Platinum.
June 24 at 8:09pm · Edited ·
Pavonne Camerer Patti, what happens if the DNA test reveals genetics from non dexter cattle? Polled dexters are firmly set within the association . Do you think the ADCA would initiate a distinction in registrations for "modern dexters" and traditional horned dexters? I think the traditional horned dexters are wonderful, and I applaud everyone who is part of the movement to preserve them, to educate dexter owners on the history, and promote them. However, I like the polled dexters too and hope that both polled and horned can be promoted through the ADCA. Thank you again for your posts. I am learning a lot from this website.
June 24 at 8:58pm ·
Patti Adams Pavonne Camerer - I don't know what the ADCA will do with the test result information. I guess we could turn the question around and ask, what will the traditional Dexter breeders expect the ADCA to do if the UC-Davis VGL breed specific test doesn't find any "other breed" markers in Saltaire Platinum's marker profile (other than the polled gene)?
June 24 at 9:15pm ·
Pavonne Camerer It is all very interesting. When do you expect the results to be in?
June 25 at 10:44am ·
Vicki Solomon I sure apprciate your knowledge and your links, Patti Adams. I am trying to learn all I can.
June 25 at 11:27am
Craig Turpin Pavonne - At the Annual General Meeting (AGM) for the ADCA, Dr. Philip Sponenberg from the u
7 hrs ·
Craig Turpin oops, hit enter. .. From the U of Virginia and the Livestock Conservancy stated that the polled gene in Dexters could have ONLY come from another breed (as the chances of the exact same gene mutating in the exact same way was infinitesimally small). Truth of the matter is that there never was any reaason to believe otherwise given SP pedigree issues. This is issue should be regarded as "resolved" once and for all: The polled gene was introduced by another breed. (If you don't mind having a Dexter that is less than 1% of some other breed, and don't want horns, go polled. If you want to preserve the original Dexter genetics, then stick to pedigrees with no ungraded/outcrossed/appendix pedigrees.)
7 hrs ·
Judy Sponaugle Darn, if transformations aren't interesting to behold! The herd record of the Godstone herd, showing all the animals and their calves and the issue with the ear marks has been on my personal website for a at best a couple years shy of a decade! The progeny records of Godstone Esmeralda and their progeny which disproved the deceit used in this country to substantiate the novel mutation have been there as well. The odds in the millions of this being a novel mutation were published in the 90s in a publication by the DCS. Just ONE year ago, ADCA commissioned Patti Adams to write a white-wash article about Godstone Esmeralda that was published in the Bulletin which said nothing of the truth of the situation or what she just posted here, this information/musing having been available in writing by Dr. Duncan MacIntyre for a number of years. One must wonder why the change in tune in just a year. DNA is the reason. You can challenge and discredit common sense, but not DNA.
