The purpose of identifying carriers is to ensure that a carrier is not bred to another carrier, thus
producing affected dogs.
In a short time we can prevent
producing Affected dogs and reduce the number of Carriers to eventually eliminate this disease just as we are working towards doing with PRCD and FN.
By judiciously using the DNA test information, breeders can minimize the risk of
producing affected dogs while maintaining the genetic diversity of the breed.
While this may all seem very complicated, the good news is that tests are available that can help breeders decrease the risk of
producing affected dogs.
Knowing which dogs carry epilepsy genes enable breeders to avoid
producing affected dogs.
Even so, breeders should take steps to avoid
producing affected dogs.
However, for breeders with dogs at high risk of being carriers and no genetic test, it is the only tool that objectively allows them to lower the risk of their breeding stock and minimize the risk of
producing affected dogs.
With this information, the breeder can plan matings that avoid
producing any affected dogs by always selecting one parent that is normal.
Pedigrees are evaluated carefully to lessen the risk of doubling up on a carrier and potentially causing a situation that could
produce affected dogs.
(Example from the pedigree: Half the sire's carrier risk is.0625 and half the dam's carrier risk is.0838, so the chance of
producing an affected dog is.0625 x.0838 =.0052 or 0.52 %.)
CA is caused by an autosomal recessive gene, which means both parents must carry the gene to
produce an affected dog.
If unknown carrier breeding stock have not
produced affected dogs, it is because they have not been involved in matings to other carriers or produced confirmed affected dogs.
The lesson here is that the only dogs whom we can say are carriers, are those who have
produced affected dogs, or are the offspring of affected dogs.
There is no test for carriers, or way to identify carriers of CA, unless
they produce an affected dog, or are the offspring of an affected dog.
As long as these dogs are bred to clear dogs, they will not
produce any affected dogs.
Not exact matches
Researchers have identified the gene mutation that causes NEwS, and a DNA test is now available that allows breeders to avoid
producing affected puppies by never breeding two
dogs to each other if they are both carriers of the abnormal gene.
«Single sex heartworm infections, host immune responses
affecting the presence of circulating microfilariae and the administration of heartworm preventives can be factors which
produce occult infections in
dogs.»
Owners or adopters of non-purebred
dogs can also help by sterilizing their pets before they become sexually mature to prevent any possibility of
producing affected offspring.
CAV - 2 also
produces pneumonia in 10 - 20 percent of the
affected dogs.
The parents and full and half siblings of an
affected dog should not be bred close on the pedigree that
produced it and should be bred to mates that do not have a family history of iris coloboma.
Carrier
dogs should only be mated to clear
dogs so as to avoid
producing BFJE
affected puppies.
Definitely do not breed
affected dogs, and do not repeat matings that
produced EPI.
A simple autosomal recessive means that the condition can occur in either sex and that it is generally transmitted by what appear to be normal animals though the late onset of the condition can result in «
affected»
dogs producing the defect because they were used prior to their «
affected» state being known.
Remove from a breeding program any
dog or bitch that is known to have repeatedly
produced any significant condition that
affects the physical or mental soundness of the progeny.
To date we have received samples from 12
dogs known to have
produced CHG
affected puppies, what we call obligate carriers, and every one has come up as a carrier on the laboratory test.
If screening detects that a
dog is predisposed to a genetic disease (or likely to
produce affected offspring) and / or perhaps already in the early stages of the disease, then no breeding can take place under the scheme.
When a breeder becomes aware that he has
produced an HD -
affected dog, he should make that information openly available through having a formal screening done through a system that allows or requires open listing, by posting the information on his website, or by seeing that the report is submitted to ASHGI's IDASH Open Health Database.
Conversely we identify normal
dogs to them with which they can continue their breeding programs secure in the knowledge that they won't
produce CHG
affected pups or more carriers.
These
dogs also
produce amyloid in organs such as the kidneys
affecting their function.
If we have a
dog that is a carrier for one or both disorders then we must breed to a clear
dog to avoid
producing any
affected puppies.
Therefore, we only test puppies that we are holding on to longer as show prospects and since we have already taken the precautions in which
dogs we have paired together before the breeding we will only be
producing clear or carriers and therefore none of our puppies will ever be
affected by these disorders specifically.
Her other mates were probably not carriers, so 50 % of the puppies were normal, 50 % were carriers, but no
affected dogs were ever
produced.
Make sure the parents of breeding stock have normal eyes, and have not
produced any PRA
affected dogs.4.
Not until she was bred to another carrier were
affected dogs produced.
In order to avoid
producing crd2 -
affected offspring, at least one
dog of any breeding pair should be homozygous Normal / Clear (See chart below).
This explains why Cyd was bred several times prior to being bred to Jordan and never
produced a PRA
affected dog.
It isn't uncommon for your
dog to
produce blood in their vomit or even blackened stools, indicating the possibility that the liver is being
affected.
In order to avoid
producing affected offspring, carriers of the rcd1b mutation should never be bred to other carriers or to
affected dogs (see chart below).
I.e., in offspring
produced by one
affected and one unaffected parent the relative risk was 1.3 times higher compared to the risk in offspring
produced by two unaffected
dogs.
However,
dogs with mild disease can
produce severely
affected offspring.
The
dog has a coat with proper furnishings but can potentially
produce offspring with Improper Coat if it is mated to another Carrier or to an IC
affected dog.
In offspring
produced by two
affected dogs the relative risk was 1.4 times higher compared to offspring from the previously mentioned mating combination and 1.8 times higher compared to offspring
produced by two unaffected
dogs.
When several cells responsible for
producing digestive enzymes are destroyed, digestion may be
affected long term and
affected dogs may develop exocrine pancreatic insufficiency.
When clinically normal
dogs produce affected offspring, it strongly suggests the disease is inherited as a simple recessive (or potentially a polygenic — multiple gene) trait, and both parents carry one «bad» copy of the gene causing the disease.
A mildly
affected dog may
produce off - spring with severe lesions.
Only 3 of the
affected dogs had an
affected parent, and breedings between an
affected and an unaffected parent could
produce either all unaffected offspring or a mix of
affected and unaffected offspring in the same litter.
Five litters (23
dogs) without
affected dogs were born to matings between parents that had both been known to
produce affected offspring.
This mode of inheritance means that one
affected dog crossed with one normal
dog will
produce puppies of which half, on average, will have the disease.
It is important to never breed two
dogs together that carry one or more copies of the mutation, in order to avoid
producing offspring that are
affected with BFJE.
Refrain from further use of any
dog / bitch that has
produced serious defects detrimental to the animal's well being,
affecting normal functions or impairment of vita