ROTT N CHATTER, February 1993, Volume 1 Number 7

 

OFA is the organization that, to date maintains the world's largest data

base on hip conformation. The purpose of OFA is to provide a standardized

evaluation for hip dysplasia and serve as the data base for control of hip

dysplasia through selective breeding.

 

Following are some interesting facts and suggestions provided by OFA.

Submitted radiographs are evaluated either NORMAL or ABNORMAL.  Only normal

hips of dogs 24 months or older are assigned a registration number and will

be reported to the parent club and to AKC.  Within the normal range are the

catagories, FAIR, GOOD, and EXCELLENT. RO-32068G24MT would be interpretated

as ROttweiler, 32,068th rated normal, GOOD, 24 months of age, MALE and

finally TATTOOED.  Within the abnormal range are the catagories, MILD,

NODERATE, and SEVERE and will be relported only to the owner of record and

referring veterinarian.

 

Between January 1974 to July 1991 of the 37,497 Rottweilers evaluated for

hip dysplasia, 23.3% were dyplastic.  Breaking the stats a little further;

of those Rottweilers BORN between the years .

 1972-1980, 4.0% = EXCELLENT while 23.8% = dysplastic.

 1981-1988, 6.3% = EXCELLENT while 23.1% = dysplastic.

 

While reviewing these figures it should be noted that not all hip xrays are

submitted to OFA, since a number of veterinarians can accurately screen a

dysplastic radiograph  an owner will not always have them submitted, hence

the figures are biased TOWARD a normal evaluation.  Of course then there

are the thousands that are never even xrayed. (I personally feel the stats

speak for themselves and the fact that almost 1/4 of our Rottweilers (that's

documented) are dysplastic is disgraceful.)

 

OFA would like to see these breeding principles.

  1.  Breed normals to normals.

  2.  Breed normals with normal ancestry.

  3.  Breed normals from litters with a low incidence of HD.

  4.  Select a sire that produces a low incidence of HD.

  5.  Replace dogs with dogs that are better than the breed average.

 

OFA also makes these suggestions

 1.  DO YOUR HOMEWORK:  Prspective buyers should check pedigrees for OFA

        numbers proir to purchasing a dog.  If an OFA number cannot be

        verified assume the dog to dysplastic until proven otherwise.

 2.  PRELIMINARY EVALUATIONS:  Can be peformed as early as 4-5 months of age

        and OFA evaluations are about 90% accurate when compared to follow-

        ups at 24 months of age.

 3.  ANESTHESIA:  Is not required by the OFA but is recommended.

 4.  HORMONAL EFFECT:  Some female dogs show subluxation when radiographed

        around an estrus cycle which is not apparent when radiographed in

        anestrus. The OFA recommends radiographing 3-4 weeks before or after

        a heat period or 3-4 weeks after weaning a litter of pups.

 

ACCORDING TO OFA:

 1.  There are no environmental factors that cause HD.

 2.  This is no scienticfic evidence that megadoses of "C" or any other

        supplement is beneficial in reducing the effects or preventing HD.

 3.  High caloric intake resulting in rapid growth and increased weight gain

        may increase changes in dysplastic hips but will not create HD.

 4.  Restricted exercise, running, jumping up and down, and slick floors

        will not cause HD.

 5.  Prior injuries to the femurs and pelvis may be detected

        radiographically and are taken into account when evaluating hip

        status.