Health testing

Accor­din­gly to the rules of Alfa Europe the dogs health must be scre­ened before they are bred. The fol­lo­wing exams are requ­ired by ALFA EU

1. Exa­mi­na­tion of hips and elbows by OFA or FCI

a. HIPS
Hip Dys­pla­sia is a ter­ri­ble gene­tic dise­ase because of the various degrees of arth­ri­tis (also cal­led dege­ne­ra­tive joint dise­ase, arth­ro­sis, oste­oar­th­ro­sis) it can even­tu­ally pro­duce, leading to pain and debilitation.

The very first step in the deve­lop­ment of arth­ri­tis is arti­cu­lar car­ti­lage (the type of car­ti­lage lining the joint) damage due to the inhe­ri­ted bad bio­me­cha­nics of an abnor­mally deve­lo­ped hip joint. Trau­ma­tic arti­cu­lar frac­ture thro­ugh the joint sur­face is ano­ther way car­ti­lage is dama­ged. With car­ti­lage damage, lots of degra­da­tive enzy­mes are rele­ased into the joint. These enzy­mes degrade and decre­ase the syn­the­sis of impor­tant con­sti­tu­ent mole­cu­les that form hyaline car­ti­lage cal­led pro­te­ogly­cans. This cau­ses the car­ti­lage to lose its thick­ness and ela­sti­city, which are impor­tant in absor­bing mecha­ni­cal loads pla­ced across the joint during move­ment. Even­tu­ally, more debris and enzy­mes spill into the joint fluid and destroy mole­cu­les cal­led gly­co­sa­mi­no­gly­can and hyalu­ro­nate which are impor­tant pre­cur­sors that form the car­ti­lage pro­te­ogly­cans. The joint’s lubri­ca­tion and abi­lity to block inflam­ma­tory cells are lost and the debris-tainted joint fluid loses its abi­lity to pro­perly nourish the car­ti­lage thro­ugh impa­ir­ment of nutrient-waste exchange across the joint car­ti­lage cells. The damage then spre­ads to the syno­vial mem­brane lining the joint cap­sule and more degra­da­tive enzy­mes and inflam­ma­tory cells stream into the joint. Full thick­ness loss of car­ti­lage allows the syno­vial fluid to con­tact nerve endings in the sub­chon­dral bone, resul­ting in pain. In an attempt to sta­bi­lize the joint to decre­ase the pain, the animal’s body pro­du­ces new bone at the edges of the joint sur­face, joint cap­sule, liga­ment and muscle attach­ments (bone spurs). The joint cap­sule also even­tu­ally thic­kens and the joint’s range of motion decreases.

No one can pre­dict when or even if a dys­pla­stic dog will start sho­wing cli­ni­cal signs of lame­ness due to pain. There are mul­ti­ple envi­ron­men­tal fac­tors such as calo­ric intake, level of exer­cise, and weather that can affect the seve­rity of cli­ni­cal signs and phe­no­ty­pic expres­sion (radio­gra­phic chan­ges). There is no rhyme or reason to the seve­rity of radio­gra­phic chan­ges cor­re­la­ted with the cli­ni­cal fin­dings. There are a num­ber of dys­pla­stic dogs with severe arth­ri­tis that run, jump, and play as if nothing is wrong and some dogs with barely any arth­ri­tic radio­gra­phic chan­ges that are seve­rely lame.

EXAMINATION OF HIP GRADING

The phe­no­ty­pic eva­lu­ation of hips done by the Ortho­pe­dic Foun­da­tion for Ani­mals falls into seven dif­fe­rent cate­go­ries. Those cate­go­ries are Nor­mal (Excel­lent, Good, Fair), Bor­der­line, and Dys­pla­stic (Mild, Mode­rate, Severe). Once each of the radio­lo­gi­sts clas­si­fies the hip into one of the 7 phe­no­ty­pes above, the final hip grade is deci­ded by a con­sen­sus of the 3 inde­pen­dent out­side eva­lu­ations. Exam­ples would be:

1. Two radio­lo­gi­sts repor­ted Excel­lent, one Good—the final grade would be Excel­lent
2. One radio­lo­gist repor­ted Excel­lent, one Good, one Fair—the final grade would be Good
3. One radio­lo­gist repor­ted Fair, two radio­lo­gi­sts repor­ted Mild—the final grade would be Mild

The hip gra­des of Excel­lent, Good and Fair are within nor­mal limits and are given OFA num­bers. This infor­ma­tion is accep­ted by AKC on dogs with per­ma­nent iden­ti­fi­ca­tion (tat­too, micro­chip) and is in the public domain. Radio­gra­phs of Bor­der­line, Mild, Mode­rate and Seve­rely dys­pla­stic hip gra­des are revie­wed by the OFA radio­lo­gist and a radio­gra­phic report is gene­ra­ted docu­men­ting the abnor­mal radio­gra­phic fin­dings. Unless the owner has cho­sen the open data­base, dys­pla­stic hip gra­des are not in the public domain.

Excel­lent

Excel­lent: this clas­si­fi­ca­tion is assi­gned for supe­rior con­for­ma­tion in com­pa­ri­son to other ani­mals of the same age and breed. There is a deep seated ball (femo­ral head) which fits tigh­tly into a well-formed soc­ket (ace­ta­bu­lum) with mini­mal joint space. There is almost com­plete cove­rage of the soc­ket over the ball.

Good

Good: sli­gh­tly less than supe­rior but a well-formed con­gru­ent hip joint is visu­ali­zed. The ball fits well into the soc­ket and good cove­rage is pre­sent.

Fair

Fair: Assi­gned where minor irre­gu­la­ri­ties in the hip joint exist. The hip joint is wider than a good hip phe­no­type. This is due to the ball sli­gh­tly slip­ping out of the soc­ket cau­sing a minor degree of joint incon­gru­ency. There may also be sli­ght inward devia­tion of the weight-bearing sur­face of the soc­ket (dor­sal ace­ta­bu­lar rim) cau­sing the soc­ket to appear sli­gh­tly shal­low. This can be a nor­mal fin­ding in some bre­eds howe­ver, such as the Chi­nese Shar Pei, Chow Chow, and Poodle.

Bor­der­line

Bor­der­line: there is no clear cut con­sen­sus between the radio­lo­gi­sts to place the hip into a given cate­gory of nor­mal or dys­pla­stic. There is usu­ally more incon­gru­ency pre­sent than what occurs in the minor amo­unt found in a fair but there are no arth­ri­tic chan­ges pre­sent that defi­ni­ti­vely dia­gnose the hip joint being dys­pla­stic. There also may be a bony pro­jec­tion pre­sent on any of the areas of the hip ana­tomy illu­stra­ted above that can not accu­ra­tely be asses­sed as being an abnor­mal arth­ri­tic change or as a nor­mal ana­to­mic variant for that indi­vi­dual dog. To incre­ase the accu­racy of a cor­rect dia­gno­sis, it is recom­men­ded to repeat the radio­gra­phs at a later date (usu­ally 6 mon­ths). This allows the radio­lo­gist to com­pare the ini­tial film with the most recent film over a given time period and assess for pro­gres­sive arth­ri­tic chan­ges that would be expec­ted if the dog was truly dys­pla­stic. Most dogs with this grade (over 50%) show no change in hip con­for­ma­tion over time and rece­ive a nor­mal hip rating; usu­ally a fair hip phenotype.

Mild

Mild Hip Dys­pla­sia: there is signi­fi­cant sub­lu­xa­tion pre­sent where the ball is par­tially out of the soc­ket cau­sing an incon­gru­ent incre­ased joint space. The soc­ket is usu­ally shal­low only par­tially cove­ring the ball. There are usu­ally no arth­ri­tic chan­ges pre­sent with this clas­si­fi­ca­tion and if the dog is young (24 to 30 mon­ths of age), there is an option to resub­mit an radio­graph when the dog is older so it can be reeva­lu­ated a second time. Most dogs will remain dys­pla­stic sho­wing pro­gres­sion of the dise­ase with early arth­ri­tic chan­ges. Since HD is a chro­nic, pro­gres­sive dise­ase, the older the dog, the more accu­rate the dia­gno­sis of HD (or lack of HD).

Mode­rate

Mode­rate Hip Dys­pla­sia: there is signi­fi­cant sub­lu­xa­tion pre­sent where the ball is barely seated into a shal­low soc­ket cau­sing joint incon­gru­ency. There are secon­dary arth­ri­tic bone chan­ges usu­ally along the femo­ral neck and head (ter­med remo­de­ling), ace­ta­bu­lar rim chan­ges (ter­med oste­ophy­tes or bone spurs) and various degrees of tra­be­cu­lar bone pat­tern chan­ges cal­led scle­ro­sis. Once arth­ri­tis is repor­ted, there is only con­ti­nued pro­gres­sion of arth­ri­tis over time.

Severe

Severe Hip Dys­pla­sia: assi­gned where radio­gra­phic evi­dence of mar­ked dys­pla­sia exi­sts. There is signi­fi­cant sub­lu­xa­tion pre­sent where the ball is par­tly or com­ple­tely out of a shal­low soc­ket. Like mode­rate HD, there are also large amo­unts of secon­dary arth­ri­tic bone chan­ges along the femo­ral neck and head, ace­ta­bu­lar rim chan­ges and large amo­unts of abnor­mal bone pat­tern changes.

FCI Hip Dys­pla­sia Registries

OFA / FCI
Excel­lent / A-1
Good / A-2
Fair / B-1
Bor­der­line / B-2
Mild / C
Mode­rate / D
Severe / E

b. ELBOWS

Elbow Dys­pla­sia Types
The Three Faces of Elbow Dysplasia

Elbow dys­pla­sia is a gene­ral term used to iden­tify an inhe­ri­ted poly­ge­nic dise­ase in the elbow of dogs. Three spe­ci­fic etio­lo­gies make up this dise­ase and they can occur inde­pen­den­tly or in con­junc­tion with one ano­ther. These etio­lo­gies include:

1. Patho­logy invo­lving the medial coro­noid of the ulna (FCP)
2. Oste­ochon­dri­tis of the medial hume­ral con­dyle in the elbow joint (OCD)
3. Unu­ni­ted anco­neal pro­cess (UAP)

Stu­dies have shown the inhe­ri­ted poly­ge­nic tra­its cau­sing these etio­lo­gies are inde­pen­dent of one ano­ther. Cli­ni­cal signs invo­lve lame­ness which may remain sub­tle for long periods of time. No one can pre­dict at what age lame­ness will occur in a dog due to a large num­ber of gene­tic and envi­ron­men­tal fac­tors such as degree of seve­rity of chan­ges, rate of weight gain, amo­unt of exer­cise, etc. Sub­tle chan­ges in gait may be cha­rac­te­ri­zed by exces­sive inward devia­tion of the paw which raises the out­side of the paw so that it rece­ives less weight and distri­bu­tes more mecha­ni­cal weight on the out­side (late­ral) aspect of the elbow joint away from the lesions loca­ted on the inside of the joint. Range of motion in the elbow is also decreased.

Elbow dys­pla­sia has mul­ti­ple inhe­ri­ted etio­lo­gies which may occur sin­gu­larly or in com­bi­na­tion. These etio­lo­gies inc­lude frag­men­ted medial coro­noid (FCP) of the ulna, oste­ochon­dri­tis of the medial hume­ral con­dyle and unu­ni­ted anco­neal pro­cess (UAP). The most sen­si­tive view used to dia­gnose secon­dary dege­ne­ra­tive chan­ges in the elbow joint is an extreme fle­xed medio-lateral view of the elbow which is requ­ired by the OFA and recom­men­ded by the Inter­na­tio­nal Elbow Wor­king Group. The vete­ri­nary radio­lo­gi­sts are most inte­re­sted in the appe­arance of the anco­neal pro­cess of the ulna.

When there is insta­bi­lity of the elbow joint due to elbow dys­pla­sia, one of the most sen­si­tive radio­gra­phic fin­dings is new bone pro­li­fe­ra­tion (oste­ophy­tes) on the anco­neal pro­cess of the ulna asso­cia­ted with secon­dary deve­lop­men­tal dege­ne­ra­tive joint disease.

Bone pro­li­fe­ra­tion can be very sub­tle to visu­alize in some dogs and may requ­ire the use of a spe­cial light source (hot light) rather than a tra­di­tio­nal view box to dia­gnose it. Other arth­ri­tic fin­dings such as scle­ro­sis in the area of the tro­chlear notch of the ulna and bone spurs at joint edges are also repor­ted. If frag­men­ta­tion of the medial coro­noid only invo­lves the car­ti­lage, it may not be seen radio­gra­phi­cally but occa­sio­nally if the bone is also frag­men­ted, it can be visu­ali­zed as a sepa­rate cal­ci­fic opa­city super­im­po­sed over the radius.

Gra­ding Elbows

For elbow eva­lu­ations, there are no gra­des for a radio­gra­phi­cally nor­mal elbow. The only gra­des invo­lved are for abnor­mal elbows with radio­gra­phic chan­ges asso­cia­ted with secon­dary dege­ne­ra­tive joint dise­ase. Like the hip cer­ti­fi­ca­tion, the OFA will not cer­tify a nor­mal elbow until the dog is 2 years of age. The OFA also accepts pre­li­mi­nary elbow radio­gra­phs. To date, there are no long term stu­dies for pre­li­mi­nary elbow exa­mi­na­tions like there are for hips, howe­ver, pre­li­mi­nary scre­ening for elbows along with hips can also pro­vide valu­able infor­ma­tion to the bre­eder.

* Grade I Elbow Dys­pla­sia: Mini­mal bone change along anco­neal pro­cess of ulna (less than 3mm).
* Grade II Elbow Dys­pla­sia: Addi­tio­nal bone pro­li­fe­ra­tion along anco­neal pro­cess (3−5 mm) and sub­chon­dral bone chan­ges (tro­chlear notch scle­ro­sis).
* Grade III Elbow Dys­pla­sia: Well deve­lo­ped dege­ne­ra­tive joint dise­ase with bone pro­li­fe­ra­tion along anco­neal pro­cess being gre­ater than than 5 mm.

2. PRCD-PRA tests of an eye

The Opti­Gen prcd-PRA Test

The Opti­Gen prcd-PRA test is a DNA-based test that helps you avoid one form of Pro­gres­sive Reti­nal Atro­phy (PRA). PRA refers to a group of dise­ases that cause the retina of the eye to dege­ne­rate slowly over time. The result is dec­li­ning vision and even­tual blind­ness. “prcd” stands for “pro­gres­sive rod-cone dege­ne­ra­tion” which is the type of PRA known in seve­ral bre­eds. AFTER reading the infor­ma­tion on this page, you can link to infor­ma­tion spe­ci­fi­cally about the breed in which you are interested.

PRA Dise­ase

The gene­tic disor­der, prcd-PRA , cau­ses cells in the retina at the back of the eye to dege­ne­rate and die, even tho­ugh the cells seem to deve­lop nor­mally early in life. The “rod” cells ope­rate in low light levels and are the first to lose nor­mal func­tion. Night blind­ness results. Then the “cone” cells gra­du­ally lose their nor­mal func­tion in full light situ­ations. Most affec­ted dogs will even­tu­ally be blind. Typi­cally, the cli­ni­cal dise­ase is reco­gni­zed first in early ado­le­scence or early adul­thood. Since age at onset of dise­ase varies among bre­eds, you sho­uld read spe­ci­fic infor­ma­tion for your dog. Dia­gno­sis of reti­nal dise­ase can be dif­fi­cult. Con­di­tions that seem to be prcd-PRA might instead be ano­ther dise­ase and might not be inhe­ri­ted. OptiGen’s gene­tic test assi­sts in making the dia­gno­sis. It’s impor­tant to remem­ber that not all reti­nal dise­ase is PRA and not all PRA is the prcd form of PRA. Annual eye exams by a vete­ri­nary oph­thal­mo­lo­gist will build a history of eye health that will help to dia­gnose disease.

Unfor­tu­na­tely, at this time there is no tre­at­ment or cure for PRA. If your dog is affec­ted, you may find it help­ful to read about other owners’ expe­rien­ces living with blind dogs. (sug­ge­sted links:www.eyevet.org and www.blinddogs.com)

Inhe­ri­tance

Prcd-PRA is inhe­ri­ted as a reces­sive trait. This means a dise­ase gene must be inhe­ri­ted from each parent in order to cause dise­ase in an offspring. Parents were either “car­rier” or affec­ted. A car­rier has one dise­ase gene and one nor­mal gene, and is ter­med “hete­ro­zy­gous” for the dise­ase. A nor­mal dog has no dise­ase gene and is ter­med “homo­zy­gous nor­mal” – both copies of the gene are the same. And a dog with two dise­ase genes is ter­med “homo­zy­gous affec­ted” – both copies of the gene are abnormal.

It’s been pro­ven that all bre­eds being tested for prcd-PRA have the same dise­ase cau­sed by the same muta­ted gene. This is so, even tho­ugh the dise­ase might deve­lop at dif­fe­rent ages or with dif­fe­ring seve­rity from one breed to another.

Altho­ugh prcd-PRA is inhe­ri­ted, it can be avo­ided in future gene­ra­tions by testing dogs before bre­eding. Iden­ti­fi­ca­tion of dogs that do not carry dise­ase genes is the key. These “clear” dogs can be bred to any mate — even to a prcd-affected dog which may be a desi­ra­ble bre­eding pro­spect for other reasons. The chance of pro­du­cing affec­ted pups from such bre­edings depends on the cer­ta­inty of test results. Again, you’ll find the spe­ci­fic infor­ma­tion on cer­ta­inty of test results for your dog by lin­king to breed spe­ci­fic infor­ma­tion.
The Gene­tic Test

The Opti­Gen prcd test is done on a small sam­ple of blood from the dog. The test ana­ly­zes the spe­ci­fic DNA muta­tion cau­sing prcd-PRA. The Opti­Gen test detects the mutant, abnor­mal gene copy and the nor­mal gene copy. The result of the test is a geno­type and allows sepa­ra­tion of dogs into three gro­ups: Normal/Clear (homo­zy­gous nor­mal), Car­rier (hete­ro­zy­gous) and Affec­ted (homo­zy­gous mutant).

Bre­eding Stra­te­gies for prcd-PRA Test:

This table high­li­ghts all the desi­ra­ble bre­edings that inc­lude at least one Normal/Clear parent. All other bre­edings are at risk of pro­du­cing Affec­ted pups with an extre­mely high pro­ba­bi­lity of deve­lo­ping prcd during their life­time. Howe­ver, all dogs can be bred safely. It isn’t neces­sary — or even desi­ra­ble — to remove dogs from the bre­eding popu­la­tion. But when cho­osing pups to retain as poten­tial bre­eding stock, it is impor­tant to select for Normal/Clear dogs and select aga­inst Affec­ted dogs.

3. Gene­ral health scre­ening
Is also requ­ired by ALFA EUROPE. Dogs to be mated must undergo this scre­ening before mating. Vet has to sign the papers (issued by ALFA EU) that he scre­aned the dog and that his con­di­tion are excel­lent. If dog or a bitch is ill they are not allo­wed to be mated.

SOURCE:

http://www.offa.org

www.optigen.com