SOUTH AFRICAN IRISH SETTER HEALTH REVIEW 2015

 

 SPECIALIST VETERINARY OPTHALMOLOGY

SAVA CLINICAL EYE EXAMINATION

Despite their being DNA tests which genetically identify Progressive Retinal Atrophy rcd 1 (early onset blindness) and LOPRA rcd 4 (late onset blindness) there are NO other genetic tests available for eye disease in Irish Setters yet The Kennel Club Centre of Animal Health Trust in Newmarket, UK has reported that a third form of PRA  exists in Irish Setters which is yet to be identified.

This is known due to an initial ten dog’s DNA samples sent for analysis which revealed 7 were affected by LOPRA rcd4 while 3 DID NOT carry either the Progressive Retinal Atrophy rcd1 or rcd4 mutation, meaning their PRA must be due to another mutation.  There is evidence that this third form has an earlier age of onset than LOPRA rcd4, but more blind dogs needed to be analysed to identify the mutation.  Currently the only way of diagnosis is by clinical examination of affected blind Irish Setters that have been genetically DNA tested and cleared of PRA rcd1 and LOPRA rcd4.

Breeders and owners can also only rely on clinical eye examinations of their Setters for the diagnosis or clearance of such conditions as Entropion which manifests as the edge of one (usually the bottom) eyelid turning inwards to the eyeball which causes damage to the cornea, Posterior Polar Cataracts (particularly in Irish Red & White Setters) and a wide range of other mild defects which may or may not be inherited such as persistent pupilliary membrane.

Clinical examination with South African Veterinarian Association Certification is undertaken by Drs. Goodhead, Venter and Lo-An Odayar who commute between their Fourways, Johannesburg Animal Hospital (011-4651237) and Cape Animal Eye Hospital , Panorama (021-9036632). Clinics in the major cities of Durban and Port Elizabeth are also held periodically throughout the year.

SAVA Examination certificates can be submitted to KUSA for capture on their data base with the request for an updated KUSA Health Screening Certificate which is an annexure to the dog’s KUSA registration Certificate.

Further information can be obtained from KUSA website under Health Schemes and website www.animaleyehospital.co.za

 

DNA TESTING FOR ADVERSE INHERITED CONDITIONS

PROGRESSIVE RETINAL ATROPHY rcd1 (PRA rcd1) & CANINE LEUCOCYTE ADHESION DEFICIENCY (CLAD)

Progressive Retinal Atrophy rcd1 is an early onset blinding condition.  As a result of genetic research, The Kennel Club Centre of the Animal Health Trust (UK) developed the first canine DNA test for Irish Setter PRA rcd 1 in the mid 1990’s. With the mating of tested CLEAR parentage it could be guaranteed their progeny would not develop nor carry the condition.

Initial research by Upsala University, Sweden led to the development of a DNA test for Canine Leucocyte Adhesion Deficiency (CLAD) a lethal auto-immune condition which gave pups in a litter little chance of survival as they were prone to any opportunistic infection.  Like PRA rcd1 the condition is also the result of a defective simple recessive mutant gene.  In 1999 a more robust test was developed by the Animal Health Trust.

Testing Laboratories for both PRA rcd 1 and CLAD are available worldwide and in South Africa are currently undertaken by Inqaba Testing Laboratory.   Such results are recognized by The Kennel Union of Southern Africa and the UK governing body of dogdom, The Kennel Club.  The local SA testing facility uses Whatman Cards which only require a few drops of blood collected from the ear of the dog by the breeder or Veterinarian for testing.

A properly structured scheme was instituted by a Group of Irish Setter Breeders in South Africa in 2006 and proved highly successful, thus in the nine years of operation we can report:

326 (three hundred and twenty-six) Irish Setters currently appear on the PRA rcd1 and CLAD National Registers as either DNA Tested Clear or Inherited Clear by virtue of tested ancestry.  In 2010 Irish Setters were the first breed to be issued with The Kennel Union of Southern Africa Health Screening Certificates which is an annexure to the KUSA Registration Certificate and currently reflect the status of the parentage and the pup together with all other health screening results.

NO cases of PRA rcd1 or CLAD have been reported and NO Carriers or Affected Irish Setters are currently recorded on KUSA Irish Setter Breed Registers or the group’s National Registers. Irish Setters imported into SA from anywhere in the world MUST be proven CLEAR of PRA rcd1 and CLAD before Breed Registration will be effected by the Kennel Union of Southern Africa.

 

LATE ONSET PROGRESSIVE RETINAL ATROPHY rcd4 (LOPRA)

In the latter half of 2011 Animal Health Trust  announced that a new form of Progressive Retinal Atrophy had been identified, initially in Gordon Setters and later in Irish Setters, which affected dogs showing rod cone degeneration (initially night blindness) beyond mid-life and blindness in later life. To distinguish this from any other form of PRA it is termed Late Onset Progressive Retinal Atrophy rcd4 (LOPRA rcd4).

Initially it was estimated that between 30 to 40% of Irish Setters were involved as Carriers in UK alone and this sent shock waves around the world as some very prominent sires were implicated. 

From August 1st 2011 The AHT offered a DNA test to Irish Setter breeders and owners which examined the DNA of each dog being tested for the presence or absence of this precise mutation.

Previously the only means of diagnosis was Clinical Eye Examination by a Specialist Veterinary Ophthalmologist of affected dogs which displayed symptoms of blindness in later life (carrying two copies of the defective gene)  Carriers (one copy of the defective gene) show no symptoms and would thus be considered clear on clinical examination. It is reasonable to assume that the mutation silently developed over a period of at least ten and probably nearer twenty years, before affected dogs were identified by Clinical Eye Examination in any numbers.

By DNA testing prior to mating any Irish Setters together the breeder acquires the knowledge to avoid breeding any pups that are LOPRA rcd 4 affected and reduce the number of Carriers, who will remain normally sighted. Those breeding clear tested mates together can guarantee Clear progeny.

CLEAR – These dogs have two normal copies of DNA.  Clear dogs will not develop LOPRA rcd 4 nor pass defective genes to progeny

CARRIER – These dogs have one copy of the simple recessive mutation gene and one normal copy, they WILL NOT DEVELOP LOPRA rcd4 but will pass one mutated gene to approximately half their progeny

AFFECTED – These dogs have two copies of the LOPRA rcd 4 gene (one inherited from each parent) and WILL GO BLIND in later life.

Immediate steps were taken at the beginning of 2012 to institute a Scheme for South African breeders and owners.  As is the case with CLAD and PRA rcd1 proposals were made to the Kennel Union of Southern Africa to prohibit the Breed Registration of any imported Irish or Gordon Setter from being placed on the respective breed register unless DNA tested Clear or proven Inherited Clear (by virtue of being the progeny of tested clear parentage) of  LOPRA rcd4.  At that time the LOPRA rcd4 status of local Setters was unknown, but it was necessary to protect SA’s limited gene pool from being further compromised. The proposals were approved by Provincial Councils and Federal Council and appear under KUSA Sch. 2 Appendix E.

Protocols and Procedures to be followed by owners/breeders participating in the Scheme were also compiled, distributed and are subscribed to on a voluntary basis. These, importantly, indicate that:

Ideally, only DNA tested CLEAR or INHERITED CLEAR parentage should be mated together to produce 100% INHERITED CLEAR PROGENY.

BUT

If a CARRIER is used for breeding purposes the following is mandatory:

ONLY CLEAR DOGS TO BE MATED TO CARRIER DOGS producing a litter which would average 50% LOPRA rcd 4 CARRIERS and 50% CLEAR progeny.

If such a mating is undertaken by a breeder it is obligatory to DNA test the ENTIRE LITTER after micro-chipping at SIX WEEKS of age.  KUSA to be requested not to Breed Register such a litter until this process is complete.

All pups to be sold with Breeders Restrictions and it should be emphasized that LOPRA rcd4 CARRIER pups from such a mating WILL NOT go blind.

LOPRA rcd4 CLEAR Setter pups from such a mating can enter the breeding gene pool with impunity and should only be mated to clear dogs within the breed.

This pattern of CLEAR to CARRIER dogs must only be undertaken in exceptional circumstances and for a limited period NOT EXCEEDING TEN YEARS FROM DATE OF COMMENCEMENT OF THE SCHEME (2013)

Irish Setters DNA tested as AFFECTED should NOT BE BRED UNDER ANY CIRCUMSTANCES neither to CLEAR and definitely NOT TO CARRIER dogs. They unfortunately will go blind and encourage the spread of the LOPRA rcd 4.

Those Setters DNA tested as CARRIERS should NOT UNDER ANY CIRCUMSTANCES be bred together (i.e.Carrier sire to Carrier dam) approximately a quarter of the litter will be AFFECTED.

To date the local Inqaba Genetic Testing Laboratory have been unable to offer a DNA test for LOPRA rcd 4 so initial testing was undertaken by the University of Missouri, America from DNA samples collected from Irish Setter owners and breeders prior to the end of 2012. Subsequently the testing laboratory was switched to Animal Heath Trust UK due to the tardiness of the University of Missouri in effecting the testing and providing proof of results.

The first batch of 27 (twenty-seven) results were received in 2013 from Missouri University and were of great concern as it was revealed that the South African gene pool had been compromised and Carriers were identified albeit that there was only one dog affected – an import from UK which had not been used at stud.  The balance tested Clear of LOPRA rcd4.

The co-ordinators of the Scheme, Mark & Bridget Simpson, advised all those who had participated of the results and, in so far as could be ascertained the direction from which they inherited the mutant LOPRA rcd4 gene.

All reports and results were subsequently forwarded to the Kennel Union of South Africa for capture on their data base and updated Health Screening Certificates were issued reflecting the status of each dog with regard to LOPRA rcd4.

With great fortitude breeders accepted the results and have juggled their breeding plans to make the best possible use of LOPRA rcd4 Clear Irish Setters to add to the pool of Inherited Clear pups. Thus we conclude 2015 with National Registers reflecting:

  •             15% Irish Setters DNA tested Clear of LOPRA rcd4
  •             66% Irish Setters Inherited Clear
  •             17% Irish Setters DNA tested Carriers
  •               2% Irish Setters DNA tested Affected

A total of 108 Irish Setter KUSA Health Screening Certificates indicating the above LOPRA rcd4 status of each dog have been issued by The Kennel Union of Southern Africa.

Progress has undoubtedly been made since the commencement of the LOPRA scheme and most breeders have elected to breed only DNA tested CLEAR or INHERITED CLEAR partners to produce Inherited CLEAR progeny. DNA LOPRA testing has been thwarted this year by the South African Postal Strikes as Animal Health Trust mail the saliva testing kits to participants.  Given SA’s “Snail Mail” when the Post Office is running normally it is advisable to courier the dog’s saliva swabs to AHT for testing albeit that this adds to the costs.

Breeders have been even harder hit by the unfavorable foreign exchange rate of Rand with the most recent hikes catapulting the Rand to Pound Sterling exchange rate to R22.50 to one Pound Sterling.  Thus the AHT £40.00 cost of the LOPRA rcd4 test per dog amounts to R900.00.  To this must be added courier fees to ensure safe arrival of samples for analysis at AHT. While expensive for South Africans, owners and breeders one hopes that all remain committed to rid the breed of LOPRA rcd4 during 2016.  It would be tragic to lose ground now when our goal is within our reach.

For further information and details of how to procure the LOPRA test kits, etc., contact Mark or Bridget Simpson mss01@telkomsa.net

Note The full Irish Setter National Registers of DNA Testing are available and will be e-mailed on request. These indicate the PRA rcd1 – CLAD –  LOPRA rcd4 status of dogs and their progeny under the headings CLEAR – CARRIER – AFFECTED (Tested dogs) and INHERITED CLEAR dogs and progeny..

 

KUSA/SAVA HIP & ELBOW X-RAY SCHEME for DYSPLASIA

No DNA test is available to determine the degree, if any, of Hip and Elbow Dysplasia in parentage prior to breeding thus no guarantee can be given by any breeder, in any breed, that progeny will be Hip and Elbow Dysplasia free. The best any breeder can do is join the KUSA/SAVA Control Scheme for diagnosis of Dysplasia whereby parentage of progeny are hip and elbow X-rayed and clinically scored by a panel of expert Veterinary Radiologists.

The commitment by the majority of Irish Setter breeders to enter the KUSA/SAVA Scheme has paid dividends. The overall mean average of Irish Setters Hip X-rayed and scored since the mid 1990’s when the scheme was opened to all breeds gives a mean average of B2:C1/C1:B2 but on review of the results in the last five years the average score has improved to B1:B2/B2:B1 interpreted under the FCI criteria as ‘near normal hip joints’ with almost half the number scoring A1’s or A2’s for each hip ‘No signs of hip dysplasia’.

KUSA Table illustrating interpretation between the “Old” South African HD Scoring System and the “New” SA internationally accepted FCI Scoring System  

 

Hip Score Comparisons

Over the years Countries and Continents developed various methods and symbols to indicate scoring results which need to be interpreted when imported dogs are being used for breeding or form part of a South African dog’s pedigree ancestry        and although comparisons cannot be completely accurate the following table of the American Orthopedic Foundation of Animals (www.offa.org) to which has been added the “old” KUSA scoring system for Hip Dysplasia is a useful aid:

OFA                            FCI                       KUSA                 BVA                    SV

America                  European &           Old System        UK/Australia       Germany                             

                            Current KUSA 

Excellent                     A-1                        0                     0-4 (no0 > 3/hip)     Normal

Good                           A-2                        0                     5-10 (no > 6/hip)     Normal

Fair                              B-1                        0                    11-18                        Normal

Borderline                   B-2                    0 or 1                 19-25                     Fast Normal

Mild                            C                           1                     26-35                Noch  Zugelassen

Moderate                    D                           2                     36-50                        Mittlere

Severe                         E                        3 or 4                 51-106                      Schwere

The addition of Elbow X-raying for dysplasia and scoring is a relatively new practice and is undertaken at the same time as X-ray of the hips while the dog is under anesthetic.  In total twenty-two Irish Setters have been X-rayed, nineteen in

the last five years  three had 0:1/1:0 scores which indicate ‘Minimal bone change along anoconeal process of ulna – less than 2mm while the balance achieved 0:0 scores ‘no signs of elbow dysplasia’.

Thus the breed is in good shape regarding Hip and Elbow Dysplasia, but only continued vigilance and commitment to X-ray and join the KUSA/SAVA Scheme will maintain this position.

On entering this Scheme there is agreement by owners that the results of scoring will be  notified, by Onderstepoort’s Prof Kirberger, who heads the panel of scrutineers, to the Kennel Union of Southern Africa for capture on their data base and subsequent update of KUSA Health Screening Certificates which are conveyed to the owner.

Further information concerning the scheme can be obtained from one’s home Veterinarian, the KUSA website www.kusa.co.za under Health Schemes or ourselves at mss01@telkomsa.net for recommendations of Veterinary Radiologists in your area.

INBREEDING COEFFICIENTS (COI)

At the commencement of 2014 a new dimension to the breeding of healthy Irish Setters in South Africa was introduced thanks to the generosity of Miss Michelle Webster and her Hooley Pedigree data base at www.hooley-irish-setters.co.uk to which she has added over 1,000 KUSA registered South African Irish Setter pedigrees. As a result, in addition to other relevant information, each dog’s Coefficient of Inbreeding is expressed as a percentage by the Wright’s Coefficient Programme which is the same system used by the Kennel Club (London) for their Breed Mate Selection site.

This is particularly helpful to SA breeders which, of necessity, work with a relatively small genetic pool compared to those in UK and Europe.  While most breeders understand that a mating between half siblings, or cousins represents inbreeding many do not understand which is the closest relationship.

Simply described “inbreeding” is that which results in progeny where the sire and the dam have common ancestry.  The parameter used to express this common heritage, is called the INBREEDING COEFFICIENT and was first used by Sewell Wright in 1922.   Designated ‘F’ by Wright, but more commonly known as COI by breeders, it ranges from 0 to 100%, the lower the percentage the less inbreeding.  Obviously the greater number of common ancestors in the pedigrees of the parentage the higher the percentage of inbreeding.

To be as accurate as possible in calculating the COI of progeny currently bred the maximum number of ancestral generation are captured and to this end the earliest SA pedigree submitted for inclusion on Hooley’s data base dates back to an exported UK dog born in 1932 and imported into SA.  Many more SA Irish Setter pedigrees of dogs imported or bred in the post world war II period have followed, up to and including those bred and KUSA registered in the course of this year. As a result breeders are now able to gain insight into the degree of inbreeding of prospective parentage by typing the name of a South African dog into Hooley Pedigree search engine.  As SA Irish Setters also have strong links to UK bred dogs it is also possible to access their ancestry and that of many other Setters around the world.

The Kennel Union of Southern Africa have been approached to include the Coefficient of Inbreeding of SA Irish Setters on their data base and on the breed’s Health Screening Certificates, but as usual the wheels of KUSA turn slowly and we await the application of this information on these certificates.

Any owner/breeder can submit Irish Setter Pedigrees of KUSA registered dogs deceased or living with any other relevant information i.e. siblings names, progeny, etc. for inclusion on Michelle’s Hooley’s data base by e-mailing a scanned copy of the KUSA certificate of Registration to mss01@telkomsa.net.  No fee is applicable for this service.

 

KUSA ADVANCED REGISTRATION CERTIFICATE (ARC)

FOR IRISH SETTERS

From the above it can be seen, that while South Africans face enormous challenges to effect health screening tests for their dogs, the majority remain committed to ensuring the future wellbeing and protection of the breed in South Africa.

Motivated by this quest a referendum was held during 2013 amongst all Irish Setter KUSA breeders and stud dog owners who were KUSA members to amend and update the existing version of the KUSA Advanced Registration Certificate for Irish Setters.  At the KUSA Federal Council Meeting In December 2013 the New Advanced Registration was approved and became applicable at the beginning of 2014.

This indicates the following:

  • 1. Positively identified by tattoo, microchip or DNA;
  • 2.Over twenty four (24) month of age;
  • 3.A Kennel Union Breed Champion;
  • 4.The registered name of the dog contains an affix (Kennel Name);
  • 5.Hip X-rayed and scored under KUSA/SAVA scheme at or after 12 months of age for dysplasia and scored no worse than C2:C2
  • 6.Elbows X-rayed and scored under KUSA/SAVA scheme for dysplasia at or after 12 months of age and scored no worse than 0:1/1:0;
  • 7.Genetically clear (normal) of Canine Leucocyte Adhesion Deficiency (CLAD) either by DNA testing or by virtue of being the progeny of DNA tested parentage (inherited clear);
  • 8.Genetically clear (normal) of Progressive Retinal Atrophy rcd1 (early onset PRA rcd1) and Late Onset Progressive Atrophy rcd4 (LOPRA rcd4) either by DNA testing or by virtue of being the progeny of DNA tested parentage (inherited clear);
  • 9.The holder of a valid SAVA Clinical Eye Examination Certificate (issued in the year of application for an ARC) stating ‘unaffected’ by any obvious eye disease or other disorder

                                        _______________________

In closing we wish to thank all owners and breeders for their co-operation during 2015  and the staff of KUSA, particularly Pascale Midgley (General Manager) and Cynthia Ross, who ensure the recording of data on KUSA systems and the issue of Health Screening Certificates so that all Irish Setter Health Screening Schemes run smoothly.

This Report is compiled and written by Mark & Bridget Simpson mss01@telkomsa.net Irish Setter Health Screening Co-ordinators South Africa.                     

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