Health Testing Our Views

Into today's Mastiff community a huge importance has been placed on testing for orthopedic disorders. We use to believe that this type of testing was a valuable tool in reducing and hopefully eliminating hip and elbow dysplasia. A large number of our dogs have been tested as can be seen on the OFA website and about as many have been prelimed but not published. We have had the privilege to get to know many reputable and long time breeders over the 18 years we have been involved in the breed. Many of us noticed very little improvement in the number of Mastiffs affected. I started watching the data reported and I have come to the conclusion that the current method of testing for hip and elbow dysplasia is ineffective. According to OFA statistics from 1974 - 1990 22.2 percent of all Mastiffs submitted were dysplastic. With 1173 Mastiffs in the OFA database. I looked up the most recent OFA statistics for Mastiffs . The number of Mastiffs now in the OFA data base is 9893, and the incidence of hip dysplasia is 19.4 percent. In the last 20 years, the percentage of Mastiffs tested and submitted has increased 840 percent yet the decreased incidence of hip dysplasia has only improved by 2.8 percent . According to a study that I posted below, the number of dysplastics may be much much higher given the increased knowledge by vets and breeders who may not ever send in films most likely not to pass. This is the reason we no longer put our dogs through this type of invasive testing. There are huge risk of putting a giant breed dog under anesthesia. Sadly I know to many that never woke up. All over the internet you will see breeders screaming that reputable, responsible breeders test for these disorders. I did this type of testing for years, and it is because I love my dogs that I will not put them through risky procedures with absolutely no evidence to support that it is helping my breeding program in any way. I do not understand what data there is to support the huge demand by a large number of breeders that we are helping our breed in the reduction of these disorders, yet the potential for harm is very real. We will continue to do our research and remain open minded as we always want to produce healthy long lived animals. If there are statistics available showing a marked reduction in the incidence of hip and elbow dysplasia in Mastiffs I would love to see it. We along with many other reputable breeders believe in breeding a Mastiff of type and temperament that comes as close as possible to our breed standard. Tested or not, a Mastiff should look like a Mastiff, impressive huge head, deep, wide, substantial body, heavy bone, structural balance and the easy going dignified Mastiff temperament. I often wonder how many breeders truly research the reliablity of these test and if they realize how subjective they are. They are only an opinion and not scientific fact. Below is an excerpt from this article. http://www.labbies.com/dysp2.htm Other external factors influencing hip ratings...What day of the week the x-rays are reviewed?!?! Subjective methods of evaluation can lead to unintentional bias and inconsistency for reproducibility of results. A study conducted at the University of Pennsylvannia revealed a startling amount of variability for hip interpretations among non-OFA and OFA board certified radiologists. When these radiologists were asked to grade hips based on the OFA rating system (excellent, good, fair, borderline CHD, mild CHD, moderate CHD or severe CHD), non-OFA readers agreed with an OFA reader in fewer than 50% of the cases. The most disturbing revelation was that when each radiologist was asked to rate certain cases a second time, each radiologist gave the same rating that he had given the first time on less than half the radiographs. Are breeders winning the battle against Canine Hip Dysplasia (CHD)? In a 1992 report on the incidence of CHD in purebred dogs, the OFA reported a 79% decrease in the occurrence of CHD when comparing dogs bred between 1972-1980 with dogs bred between 1981-1988. Though upon first glance, this data suggests a significant advance in the control of CHD, it was recognized that some variables had not been controlled for in the study. For example, this data would only be relevant if all hip radiographs (X-rays) were sent to the OFA for review. However, a review of records at the Veterinary Hospital of the University of Pennsylvannia (VHUP) indicated that only half of clients having their dogs x-rayed for the purpose of acquiring OFA certification actually ended up submitting the radiographs to the OFA for review. It was determined that clients only submitted radiographs of dogs having the greatest likelihood of being certified. In comparison to the OFA's reports for breed-specific incidence of CHD, a clinical survey conducted at VHUP demonstrated breed-specific incidence of CHD to be 2-3 times higher than reported by the OFA. I suspect many breeders just follow blindly what they are told all over the internet without doing the research to find out if these test are beneficial to their dogs, their breeding program, and the breed as a whole. New breeders are fearful of being ridiculed if they do not follow the norm. Testing has become a huge sales pitch. It gives buyers a false sense of security, and breeders justification for breeding mediocre stock. The general public believes if the parents are tested for these joint disorders that their pup will be free of these disorders as well. Unfortunately that is far from the truth.