PHA Question
- Thread starter cowz
- Start date
Help Support Steer Planet:
[size=10pt][size=10pt]justme said:
EASY GUYS IT WAS A JOKE!! Perhaps we have all ventured too far off the planet and it has jaded our usual delightful beings!! ;D ;D ;D[/size][/size] (lol) (lol) (lol) (lol)
(MAYBE i SHOULD PULL MY OWN POST??) (cow) (cow) (cow)
red
Well-known member
Naw, leave it- it's fine. I think we all need spring! I know I sure do!
Deep cleansing breathes! Assume the locust postition, ah... don't we all feel better now?
(clapping)
Red
Deep cleansing breathes! Assume the locust postition, ah... don't we all feel better now?
(clapping)
Red
JbarL
Well-known member
does pha and th effect all breeds? what breeds are more/less prominet? thanks jbarldragon lady said:
hey you ol'd hippie - I worte this for something else but instead of re inventing the wheel - here ya go! dl
Tibial hemimelia (TH)
Tibial hemimelia was first described in Galloway cattle in the 1970’s. Way before genetic testing, TH was virtually eliminated in the Galloway breed using pregnancy termination to identify known carriers. TH has recently reared its ugly head in US cattle. TH is a lethal autosomal recessive genetic disorder – calves are born with a variety of skeletal abnormalities, abdominal hernias, meningocele, cryptorchid, and long hair. Calves are usually born dead, but occasionally may be born alive.
After an exhaustive hunt to obtain samples and pedigrees by Dr Chuck Hannon and Shorthorn breeders in the midwest, the gene responsible for TH and the bull that brought TH to the US was identified. Examining hundreds of samples from TH calves and their relatives, Dr. Jon Beever and Brandy Marron at the University of Illinois were able to identify the defective gene responsible for TH. The gene codes for a protein responsible for the formation of the rear legs during early development. The defect in the gene that results in TH is a deletion – part of the gene is missing. A genetic test for carriers of the defective TH gene has been developed and is commercially available.
Examining pedigrees in conjunction with the genetic studies, lead to the identification of the bull Deerpark Improver as the origin of the TH gene in the Shorthorn breed. The deletion has become known as the “Improver deletion”. Interestingly, there were documented TH calves that parentally verified to a bull called TKA Outcast, but Outcast did not test positive for the Improver deletion. Further investigation showed a second larger deletion of the same gene in the bull, the so-called “Outcast” deletion. This deletion is very rare when compared to the Improver deletion. It is unknown if the Galloway defect is the same as the Shorthorn defect - there are no samples from carrier Galloways available for testing.
The defective gene traces to the Shorthorn breed, and consequently can be found in any breed or composite with Improver genetics. The Shorthorn web site lists results from animals tested for TH and parentally verified. Of the 2352 animals listed (1586 females and 766 bulls), 384 are carriers (259 females and 125 bulls). To date over 75 popular AI bulls have been identified as TH carriers. In the last year over 10,480 cattle have been tested for TH. It is generally believed that carriers of the defective gene have a phenotype that is desirable in the show ring and the apparent large number of carrier animals is the result of chasing a phenotype.
Pulmonary hypoplasia with anasarca (PHA)
In the hunt for TH, Dr Hannon found another defect now known as PHA. PHA calves have very small lungs, their tissues are filled with fluid, and the lymphatic system is abnormal. PHA can result in death of both the calf and the cow. Dystocia is often the problem. Calves can weigh over 200 pounds, may require C-section for delivery, and are generally born dead. In some cases calves are so huge they cannot be removed even after C-section and the cow must be killed. It is now known that PHA calves may be aborted at any time during gestation and are often born early, which has lead to some confusion about the sire of some PHA calves. PHA is also a recessive genetic disorder.
PHA traces to Maine-Anjou genetics. In fact, two Maine-Anjou bulls (Draft Pick and Stinger) and a composite bull with Maine genetics (Payback) were identified as early propagators of the defective PHA gene. There are three distinct DNA marker "haplotypes" (a combination of different marker alleles) in Stinger, Draftpick and Payback and these haplotypes are related. Given the distance between these markers, rearrangement of the haplotypes only occurs once in about 500 to 1000 offspring. Thus, for all three bulls to have these different haplotypes the common ancestor has to be back several generations from each. For instance, all carrier individuals going back to Draft Pick within four generations, have the same haplotype. Payback should be considered at the same level as Stinger and Draft Pick in regard to pedigree distance from a common ancestor.
Of the three bulls, Draft Pick had the most accurate and complete pedigree and the most offspring and relatives available for use to identify the defective gene. Again, Dr. Beever and Brandy Marron worked tirelessly to identify the defective gene – in this case the gene codes for a well conserved protein whose function is not entirely known and the mutation is a single substitution of one amino acid for another. Based on identification of the defective gene, a test for the PHA gene was developed.
Using this test, Draft Pick’s male relatives were screened for the PHA gene – his sire (NorTex General) and his maternal sire (AA Black Gold 500) are not PHA carriers, however, Paramount (maternal great grand sire) is a carrier. Despite exhaustive searching, no common carrier animals have been identified in Stinger and Payback. Payback’s pedigree is incomplete and there are now questions about the accuracy of Stinger’s pedigree.
Recently PHA was identified in Dexter cattle in Australia. While the same gene is involved in both breeds, the mutation is different in Dexter and Maine-Anjou cattle. To date over 60 popular AI bulls have been identified as PHA carriers. Any animal that traces to Draft Pick, Stinger or Payback can potentially carry the PHA gene. Since November 2006 over 4000 cattle have been tested for PHA.
Cattle that trace to both Shorthorn (Improver) and Maine-Anjou genetics have the potential to carry both defects. To date at least 15 commonly used AI bulls
(cow) (cow)
Tibial hemimelia (TH)
Tibial hemimelia was first described in Galloway cattle in the 1970’s. Way before genetic testing, TH was virtually eliminated in the Galloway breed using pregnancy termination to identify known carriers. TH has recently reared its ugly head in US cattle. TH is a lethal autosomal recessive genetic disorder – calves are born with a variety of skeletal abnormalities, abdominal hernias, meningocele, cryptorchid, and long hair. Calves are usually born dead, but occasionally may be born alive.
After an exhaustive hunt to obtain samples and pedigrees by Dr Chuck Hannon and Shorthorn breeders in the midwest, the gene responsible for TH and the bull that brought TH to the US was identified. Examining hundreds of samples from TH calves and their relatives, Dr. Jon Beever and Brandy Marron at the University of Illinois were able to identify the defective gene responsible for TH. The gene codes for a protein responsible for the formation of the rear legs during early development. The defect in the gene that results in TH is a deletion – part of the gene is missing. A genetic test for carriers of the defective TH gene has been developed and is commercially available.
Examining pedigrees in conjunction with the genetic studies, lead to the identification of the bull Deerpark Improver as the origin of the TH gene in the Shorthorn breed. The deletion has become known as the “Improver deletion”. Interestingly, there were documented TH calves that parentally verified to a bull called TKA Outcast, but Outcast did not test positive for the Improver deletion. Further investigation showed a second larger deletion of the same gene in the bull, the so-called “Outcast” deletion. This deletion is very rare when compared to the Improver deletion. It is unknown if the Galloway defect is the same as the Shorthorn defect - there are no samples from carrier Galloways available for testing.
The defective gene traces to the Shorthorn breed, and consequently can be found in any breed or composite with Improver genetics. The Shorthorn web site lists results from animals tested for TH and parentally verified. Of the 2352 animals listed (1586 females and 766 bulls), 384 are carriers (259 females and 125 bulls). To date over 75 popular AI bulls have been identified as TH carriers. In the last year over 10,480 cattle have been tested for TH. It is generally believed that carriers of the defective gene have a phenotype that is desirable in the show ring and the apparent large number of carrier animals is the result of chasing a phenotype.
Pulmonary hypoplasia with anasarca (PHA)
In the hunt for TH, Dr Hannon found another defect now known as PHA. PHA calves have very small lungs, their tissues are filled with fluid, and the lymphatic system is abnormal. PHA can result in death of both the calf and the cow. Dystocia is often the problem. Calves can weigh over 200 pounds, may require C-section for delivery, and are generally born dead. In some cases calves are so huge they cannot be removed even after C-section and the cow must be killed. It is now known that PHA calves may be aborted at any time during gestation and are often born early, which has lead to some confusion about the sire of some PHA calves. PHA is also a recessive genetic disorder.
PHA traces to Maine-Anjou genetics. In fact, two Maine-Anjou bulls (Draft Pick and Stinger) and a composite bull with Maine genetics (Payback) were identified as early propagators of the defective PHA gene. There are three distinct DNA marker "haplotypes" (a combination of different marker alleles) in Stinger, Draftpick and Payback and these haplotypes are related. Given the distance between these markers, rearrangement of the haplotypes only occurs once in about 500 to 1000 offspring. Thus, for all three bulls to have these different haplotypes the common ancestor has to be back several generations from each. For instance, all carrier individuals going back to Draft Pick within four generations, have the same haplotype. Payback should be considered at the same level as Stinger and Draft Pick in regard to pedigree distance from a common ancestor.
Of the three bulls, Draft Pick had the most accurate and complete pedigree and the most offspring and relatives available for use to identify the defective gene. Again, Dr. Beever and Brandy Marron worked tirelessly to identify the defective gene – in this case the gene codes for a well conserved protein whose function is not entirely known and the mutation is a single substitution of one amino acid for another. Based on identification of the defective gene, a test for the PHA gene was developed.
Using this test, Draft Pick’s male relatives were screened for the PHA gene – his sire (NorTex General) and his maternal sire (AA Black Gold 500) are not PHA carriers, however, Paramount (maternal great grand sire) is a carrier. Despite exhaustive searching, no common carrier animals have been identified in Stinger and Payback. Payback’s pedigree is incomplete and there are now questions about the accuracy of Stinger’s pedigree.
Recently PHA was identified in Dexter cattle in Australia. While the same gene is involved in both breeds, the mutation is different in Dexter and Maine-Anjou cattle. To date over 60 popular AI bulls have been identified as PHA carriers. Any animal that traces to Draft Pick, Stinger or Payback can potentially carry the PHA gene. Since November 2006 over 4000 cattle have been tested for PHA.
Cattle that trace to both Shorthorn (Improver) and Maine-Anjou genetics have the potential to carry both defects. To date at least 15 commonly used AI bulls
(cow) (cow)
JbarL
Well-known member
thanks dl........i cant thank you all enough....with the discussing i've been reading and information i've gotten here ( although it is kinda scary) for me being an absent owner, it was giving me just one more thing to consider......but i think i'm armeed with some great info and feel confident in discussions in the futre with my breeder and our future plans...it sounds like the main caracters in the show have been identified and at least can be controlled with information sharing like this and integrity, it sounds like a great reason to look at reds recently post concerning a genitcs area for fourm..not only the defects but the progress with correct sound tracking and information sharing like this for me as a newcommer is the best tool i have in this genre..and more to come for sure, but this is where i jumbed in at....use hippes have to do all the logical thinking..alwasy have always will...thanks angain folks,,,jbarl
jbarL - just an added tidbit or sticky wicket - if you buy Maine, Maine cross, Shorthorn, crossbred cows _ I would have them tested - although there are some definite red flags with potential problem pedigrees recent evidence suggests that either (1) a bundh of pedigrees are bogus or (2) other operatives are at work! stayed tuned to this planet - all the news that is fit to print, a modicum of levity, a sticky wicket and a bunch of good people - how could life be better? dl
Latest posts
-
-
-
-
Looking for info on the Grand Champion bull from the 1971 Buckeye Expo
- Latest: wannabcowguy
