C.S.N.B (Congenital Stationary Night Blindness)
Congenital Stationary Night Blindness is an inherited eye problem discovered in British Briards a few years ago although it is well documented in North America and Europe.
We are fortunate to have a D.N.A. test available in this country via the Animal Health Trust (A.H.T.) www.aht.org.uk
Buccal swabs can be obtained by phoning the A.H.T. on 0870 0509144 or email [email protected] there is really no excuse for not having breeding stock tested as one test covers a Briard for life. Indeed this is a condition/rule of membership of our Club.
We have the knowledge to breed safely and responsibly with regard to C.S.N.B. and the following may also be of use as a reminder of how the inheritance works for this problem.
We are fortunate to have a D.N.A. test available in this country via the Animal Health Trust (A.H.T.) www.aht.org.uk
Buccal swabs can be obtained by phoning the A.H.T. on 0870 0509144 or email [email protected] there is really no excuse for not having breeding stock tested as one test covers a Briard for life. Indeed this is a condition/rule of membership of our Club.
We have the knowledge to breed safely and responsibly with regard to C.S.N.B. and the following may also be of use as a reminder of how the inheritance works for this problem.
Each parent passes on one gene to its offspring. The status of that gene will be either affected, carrier or clear. Thus:
1. Affected mated to affected will produce 100% affected puppies (heaven forbid!)
2. Affected to carrier will produce 50% affected and 50% carriers (not advisable!)
3. Affected to clear will produce 100% carriers (OK?)
4. Carrier to carrier will produce 25% affected, 25% clear and 50% carrier. (not advisable)
5. Carrier to clear will produce 50% carrier and 50% clear (OK)
6. Clear to clear will produce 100% clear (wonderful, and no need to test the puppies as they will all be genetically/hereditarily clear.)
The aim is obviously never to breed another affected Briard thus examples 1, 2, and 4 should be avoided.
If you are not fortunate enough to receive a clear test result with your current breeding stock do not despair as by following example 3 or 5 you can breed clear stock in one or two generations, which should be the aim of all breeders.
If you wish to use a dog at stud ask the question "has he been tested?", likewise expect the owner of the stud dog to ask you the same question regarding your bitch and to see test results or proof of hereditary status.
PUPPY BUYERS SHOULD ALSO ASK THE SAME QUESTION AND REQUIRE PROOF
Test results are now published by the Kennel Club and can be found at:
http://www.thekennelclub.org.uk/item/1136
In 2010 following consultation with, and agreement by both breed clubs, a proposal for a C.S.N.B. policy was submitted to the Kennel Club.
I am pleased to report that, with only one alteration it has now been approved and is printed in full below.
Hopefully, this should mean the eradication of C.S.N.B. in U.K. Briards.
From 1st January 2013
1. All Briards used for breeding should be either proven hereditarily clear of CSNB or have a CSNB DNA test before they are used for breeding.
2. Identified carriers can be used for breeding providing that they are only mated to a Briard that is either hereditarily clear or DNA tested clear of CSNB. Carriers should not be mated to carriers and the Kennel Club will refuse to register any progeny resulting from such a mating.
3. All of the offspring of a carrier mated to a clear should be clearly identified, DNA tested and registered as either tested clear or carrier.
From 1st January 2015
1. The Kennel Club will cease to routinely accept any new registrations for Briard progeny produced from a CSNB carrier parent mated to a clear parent (either DNA tested or hereditarily clear).
Breeders wishing to register progeny from a carrier after this date will need to apply for permission prior to the proposed mating, and applications will be dealt with on a case by case basis involving input from the Breed Clubs.
2. If such permission is given and a carrier is mated to a DNA tested or hereditarily clear dog all progeny must be DNA tested and registered with the Kennel Club as either CSNB Clear or Carrier.
3. The Kennel Club will place K.C. endorsements on the carrier progeny such that if they are bred from without the necessary approval sought beforehand, their progeny will not be able to be registered with the Kennel Club.
1. Affected mated to affected will produce 100% affected puppies (heaven forbid!)
2. Affected to carrier will produce 50% affected and 50% carriers (not advisable!)
3. Affected to clear will produce 100% carriers (OK?)
4. Carrier to carrier will produce 25% affected, 25% clear and 50% carrier. (not advisable)
5. Carrier to clear will produce 50% carrier and 50% clear (OK)
6. Clear to clear will produce 100% clear (wonderful, and no need to test the puppies as they will all be genetically/hereditarily clear.)
The aim is obviously never to breed another affected Briard thus examples 1, 2, and 4 should be avoided.
If you are not fortunate enough to receive a clear test result with your current breeding stock do not despair as by following example 3 or 5 you can breed clear stock in one or two generations, which should be the aim of all breeders.
If you wish to use a dog at stud ask the question "has he been tested?", likewise expect the owner of the stud dog to ask you the same question regarding your bitch and to see test results or proof of hereditary status.
PUPPY BUYERS SHOULD ALSO ASK THE SAME QUESTION AND REQUIRE PROOF
Test results are now published by the Kennel Club and can be found at:
http://www.thekennelclub.org.uk/item/1136
In 2010 following consultation with, and agreement by both breed clubs, a proposal for a C.S.N.B. policy was submitted to the Kennel Club.
I am pleased to report that, with only one alteration it has now been approved and is printed in full below.
Hopefully, this should mean the eradication of C.S.N.B. in U.K. Briards.
From 1st January 2013
1. All Briards used for breeding should be either proven hereditarily clear of CSNB or have a CSNB DNA test before they are used for breeding.
2. Identified carriers can be used for breeding providing that they are only mated to a Briard that is either hereditarily clear or DNA tested clear of CSNB. Carriers should not be mated to carriers and the Kennel Club will refuse to register any progeny resulting from such a mating.
3. All of the offspring of a carrier mated to a clear should be clearly identified, DNA tested and registered as either tested clear or carrier.
From 1st January 2015
1. The Kennel Club will cease to routinely accept any new registrations for Briard progeny produced from a CSNB carrier parent mated to a clear parent (either DNA tested or hereditarily clear).
Breeders wishing to register progeny from a carrier after this date will need to apply for permission prior to the proposed mating, and applications will be dealt with on a case by case basis involving input from the Breed Clubs.
2. If such permission is given and a carrier is mated to a DNA tested or hereditarily clear dog all progeny must be DNA tested and registered with the Kennel Club as either CSNB Clear or Carrier.
3. The Kennel Club will place K.C. endorsements on the carrier progeny such that if they are bred from without the necessary approval sought beforehand, their progeny will not be able to be registered with the Kennel Club.
