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hadn't heard of this before. not sure it isn't a more severe form or is spastic paresis.https://translate.google.com/translate?hl=en&sl=fr&u=http://bovins-viande.reussir.fr/actualites/avec-la-genetique-moleculaire-connaitre-et-eradiquer-les-anomalies-genetiques:UUE5FXNC.html&prev=searchThe episodic occurrence of genetic abnormalities is unfortunately inevitable. It's even normal! This is the lot of all selected races, due to cattle breeding practices which widely use some breeders because they are the best. Indeed, we now know that all animals are carriers of one or more mutations likely to be the cause of a genetic abnormality. Most of these abnormalities are due to a single gene (monogenic) and a mode of transmisson autosomal recessive (see also box).In this case, a player carries a mutation will cause a genetic abnormality that if his descendant inherits this mutation and it inherits the same mutation of the other parent. Fortunately it is very rare that such a situation arises. Yet, it happens. The animal insemination is only the vector of this phenomenon. By against inbreeding influences the importance of genetic diseases is more important and more were likely to give birth to calves homozygotes who develop the disease.These genetic diseases cause significant economic losses in livestock, and they damage the image of a race. The good news is that we now have methods and tools to deal with it, without taboo. The National Observatory of bovine anomalies was set up in 2002 at the INRA initiative with the participation of national professional organizations involved in cattle breeding.
DETECT EARLY TO REACT ON TIMEIn the 1990s and early 2000s, rapid emergence had observed several anomalies in Holstein breed, including lethal abnormality "Bulldog", manifested among others by reduced bone growth and Member face, or the CVM (Congenital malformations Vertebral). Also lethal, this anomaly results in malformations of the spine. "In the case of CVM, the Danes, who already had an observatory genetic defects, were able to respond quickly and clearly better manage this crisis we are. The need to develop such a tool in France then appeared very clearly, "says Amandine Duchesne of INRA of Jouy-en-Josas, co-host of ONAB.The role of the observatory is to first identify all forms of abnormalities in breeding calves at birth or later in their development. The collection of information is the only way to detect possible emergence of a new genetic abnormality. "It is important to react as early as possible. For a given anomaly, the number of cases reported to the ONAB is often extremely low. It is somehow just the tip of the iceberg. But the frequency of certain mutations can evolve very rapidly at times. This is what we have taught the case of BLAD (Bovine Leukocyte Adhesion Deficiency) and CVM in Holstein breed, "says Amandine Duchesne.From a dozen cases for the same anomaly, a study can be launched. The first step is to assess the possibility of hereditary given the genealogy of affected animals. "If the hypothesis of a genetic determinism is validated, an accurate description of the disease is performed most often in collaboration with veterinary schools. Then we go immediately to biological samples and of samples for genotyping chip high-density DNA. "This can quickly lead to obtaining a genetic test.Indeed, genotyping can be located more or less precisely the portion of the DNA where the mutation is located. Researchers can then propose an indirect genetic test based on markers of the region containing the mutation. Even if they are not 100% reliable as can Letre direct mutation-based test, these tests generally allow to sort efficiently between carrier animals and nonporteurs. "For example a test of markers allowed the anomaly déradiquer SHGC in Montbeliarde breed (generalized hypoplasia syndrome capréolifirme) even before the mutation is found," says Amandine Duchesne. To identify the causal mutation - and thus have a direct test - further studies can be pursued, such as the comparative sequencing of healthy and sick animals for the region containing the mutation.
When an anomaly is identified, a genetic test is developed, that is the breeding organization of the breed to decide on the actions to implement. These will be based on the frequency of the anomaly in the population, and the economic impact of the disease.It is essentially on the male pathway that actions will bring. It can be removed simply catalog insemination bulls which reveal carriers of the anomaly. If the genetic value of bulls heterozygous carriers of a mutation is very high, it is still possible to set up a management abnormality. Of matings are intended to avoid as much as possible the birth of sick calves and gradually decrease the frequency of the mutation in the population.
The "calf turner" in the Red Meadow race on track to eradicateRed Meadow is the first French suckler race which dares to address the eradication of a genetic abnormality. This is to kick a complex disease that has not yet revealed all its secrets to researchers, which is very rare in the race. Syndrome "calf turner" is a degenerative nerve disease. She appeared there about ten years and cases have been reported from 2009 Oniris (1). The calf has a birth and develop normally until about the age of 1 to 3 months. Then appear ataxia (incoordination) and paresis (weakness) of the hind limbs that result in a turning movement when he moves up to drop it. This gets progressively worse in one to three months, until the animal no longer rises. This is a fatal disease, calves with generally euthanized before the age of 4 months. Such lesions of the spinal cord can not be cured.
TAKING A SICK TIME"
We decided to take this disease very seriously. There were very few cases of 'calves turners', but we know that this disease could become much greater, "says Ghislain Aminot of Sica Rouge des Prés. The selection committee, in collaboration with INRA in Jouy-en-Josas and Oniris, then called breeders to testify about it. Some farmers came forward and a dozen calves were studied. They have identified a genetic origin for the disease, and to identify a founder strain of the disease. Genotyping of sick animals was then undertaken. The study to develop an indirect DNA test, which helps answer the question of whether the animal is a carrier of the anomaly "calf turner" or not (haplotypes). The INRA researchers are continuing their work in order to offer a more accurate test. These first results have already allowed the OS Rouge des Prés define a struggle against the abnormality strategy "calf turner", only a year after the start of the study. The OS board decided déradiquer this genetic disease. For this, the easiest is to act on the male pathway. In 2010, four insemination bulls carriers of the anomaly were removed from the catalog (Ino, moldboard, Sarazin and Tendon). It remains one carrier bull catalog, Bouba, who wasnt so not yet in circulation and that is genetically interesting. He had to live in a country with a somewhat reduced insemination catalog, and rétoffer the following year. In 2011, the catalog shall include the status of bulls in relation to the anomaly "calf turner." About half of the bulls are still undetermined, other carriers are not qualified. "We are on track. The disease was caught in time: the risk of spread of the disease has already spread and the number of cases should start with lower birth this fall. "
TRANSPARENCY
A screening test animals carrying the rapid and inexpensive genetic abnormality is expected for 2012. It will test farm of natural service bulls. "In the future, we believe that the calves will be tested before they take devaluation station. "One should hear about" calf turner "in four to five years. Meadows Red breeders are very satisfied with how this problem was treated. Be informed in full transparency, better understand how the genetic abnormality is actually very reassuring.
In practiceDeclare the birth of a calf 'abnormal'All breeders can register the birth of a calf which they consider "abnormal" at the National Observatory of bovine genetic abnormalities, directly or by appealing to their technician or their veterinarian. Record a simple to use information collection is available on the website of the Observatory (under "declare an anomaly"). It is important to make this statement as soon as possible for the Centre to fulfill its role of alert. All information of interest to leaders of ONAB, simple pigmentation defect to the most complex neurological syndrome, the genetic origin is known or not. later onset to anomalies such as neurodegenerative diseases such as ataxia or some axonopathies are also to report to the Observatory. http://www.onab.fr
DETECT EARLY TO REACT ON TIMEIn the 1990s and early 2000s, rapid emergence had observed several anomalies in Holstein breed, including lethal abnormality "Bulldog", manifested among others by reduced bone growth and Member face, or the CVM (Congenital malformations Vertebral). Also lethal, this anomaly results in malformations of the spine. "In the case of CVM, the Danes, who already had an observatory genetic defects, were able to respond quickly and clearly better manage this crisis we are. The need to develop such a tool in France then appeared very clearly, "says Amandine Duchesne of INRA of Jouy-en-Josas, co-host of ONAB.The role of the observatory is to first identify all forms of abnormalities in breeding calves at birth or later in their development. The collection of information is the only way to detect possible emergence of a new genetic abnormality. "It is important to react as early as possible. For a given anomaly, the number of cases reported to the ONAB is often extremely low. It is somehow just the tip of the iceberg. But the frequency of certain mutations can evolve very rapidly at times. This is what we have taught the case of BLAD (Bovine Leukocyte Adhesion Deficiency) and CVM in Holstein breed, "says Amandine Duchesne.From a dozen cases for the same anomaly, a study can be launched. The first step is to assess the possibility of hereditary given the genealogy of affected animals. "If the hypothesis of a genetic determinism is validated, an accurate description of the disease is performed most often in collaboration with veterinary schools. Then we go immediately to biological samples and of samples for genotyping chip high-density DNA. "This can quickly lead to obtaining a genetic test.Indeed, genotyping can be located more or less precisely the portion of the DNA where the mutation is located. Researchers can then propose an indirect genetic test based on markers of the region containing the mutation. Even if they are not 100% reliable as can Letre direct mutation-based test, these tests generally allow to sort efficiently between carrier animals and nonporteurs. "For example a test of markers allowed the anomaly déradiquer SHGC in Montbeliarde breed (generalized hypoplasia syndrome capréolifirme) even before the mutation is found," says Amandine Duchesne. To identify the causal mutation - and thus have a direct test - further studies can be pursued, such as the comparative sequencing of healthy and sick animals for the region containing the mutation.
When an anomaly is identified, a genetic test is developed, that is the breeding organization of the breed to decide on the actions to implement. These will be based on the frequency of the anomaly in the population, and the economic impact of the disease.It is essentially on the male pathway that actions will bring. It can be removed simply catalog insemination bulls which reveal carriers of the anomaly. If the genetic value of bulls heterozygous carriers of a mutation is very high, it is still possible to set up a management abnormality. Of matings are intended to avoid as much as possible the birth of sick calves and gradually decrease the frequency of the mutation in the population.
The "calf turner" in the Red Meadow race on track to eradicateRed Meadow is the first French suckler race which dares to address the eradication of a genetic abnormality. This is to kick a complex disease that has not yet revealed all its secrets to researchers, which is very rare in the race. Syndrome "calf turner" is a degenerative nerve disease. She appeared there about ten years and cases have been reported from 2009 Oniris (1). The calf has a birth and develop normally until about the age of 1 to 3 months. Then appear ataxia (incoordination) and paresis (weakness) of the hind limbs that result in a turning movement when he moves up to drop it. This gets progressively worse in one to three months, until the animal no longer rises. This is a fatal disease, calves with generally euthanized before the age of 4 months. Such lesions of the spinal cord can not be cured.
TAKING A SICK TIME"
We decided to take this disease very seriously. There were very few cases of 'calves turners', but we know that this disease could become much greater, "says Ghislain Aminot of Sica Rouge des Prés. The selection committee, in collaboration with INRA in Jouy-en-Josas and Oniris, then called breeders to testify about it. Some farmers came forward and a dozen calves were studied. They have identified a genetic origin for the disease, and to identify a founder strain of the disease. Genotyping of sick animals was then undertaken. The study to develop an indirect DNA test, which helps answer the question of whether the animal is a carrier of the anomaly "calf turner" or not (haplotypes). The INRA researchers are continuing their work in order to offer a more accurate test. These first results have already allowed the OS Rouge des Prés define a struggle against the abnormality strategy "calf turner", only a year after the start of the study. The OS board decided déradiquer this genetic disease. For this, the easiest is to act on the male pathway. In 2010, four insemination bulls carriers of the anomaly were removed from the catalog (Ino, moldboard, Sarazin and Tendon). It remains one carrier bull catalog, Bouba, who wasnt so not yet in circulation and that is genetically interesting. He had to live in a country with a somewhat reduced insemination catalog, and rétoffer the following year. In 2011, the catalog shall include the status of bulls in relation to the anomaly "calf turner." About half of the bulls are still undetermined, other carriers are not qualified. "We are on track. The disease was caught in time: the risk of spread of the disease has already spread and the number of cases should start with lower birth this fall. "
TRANSPARENCY
A screening test animals carrying the rapid and inexpensive genetic abnormality is expected for 2012. It will test farm of natural service bulls. "In the future, we believe that the calves will be tested before they take devaluation station. "One should hear about" calf turner "in four to five years. Meadows Red breeders are very satisfied with how this problem was treated. Be informed in full transparency, better understand how the genetic abnormality is actually very reassuring.
In practiceDeclare the birth of a calf 'abnormal'All breeders can register the birth of a calf which they consider "abnormal" at the National Observatory of bovine genetic abnormalities, directly or by appealing to their technician or their veterinarian. Record a simple to use information collection is available on the website of the Observatory (under "declare an anomaly"). It is important to make this statement as soon as possible for the Centre to fulfill its role of alert. All information of interest to leaders of ONAB, simple pigmentation defect to the most complex neurological syndrome, the genetic origin is known or not. later onset to anomalies such as neurodegenerative diseases such as ataxia or some axonopathies are also to report to the Observatory. http://www.onab.fr
