Editor’s note: Stephanie Abraham is the ABC columnist for the AKC Gazette. The following is her January 2000 Gazette column, reprinted here with the permission of the author.

I belong to one of the Internet e-mail lists focusing on the Boxer. The list is informative, timely and competently administered. Recently, a great deal of information, some accurate, some distorted and some downright silly, has circulated on this list regarding the proper protocols for testing Boxers for various health conditions. What is a breeder supposed to do to help ensure the health of Boxers?

If I were to follow the advice of the most fervent among us, I would certainly not fail to test my stock for two of the breed’s most critical medical problems -- the very serious heart ailments, subaortic stenosis (SAS) and Boxer cardiomyopathy (BCM). I am admonished by some very vocal peers that not to test is to do the breed a great disservice, to ignore potentially life- threatening ailments, and to take a callous view of the breed we love.

I say, not necessarily so!

Those of us who are medically informed and have been in Boxers for more than just a few years know that a disturbing number of Boxers suffer from SAS or BCM, with the latter condition often not evident until midlife or later. If, as evidence strongly suggests, these conditions are inheritable, then of course we must weed afflicted animals out of the breeding population. But therein lies the proverbial rub.

To date, there have been no medical protocols developed in this country to tell us what is a normal heart reading for the breed -- not what is normal for the Doberman or the Dane or the Beagle, but for the Boxer. In Britain, a murmur of Grade 2 or above and a Doppler echo showing a blood velocity rate of 2.0 or greater is considered to be suspicious for SAS. Would the same criteria apply to Boxers here? When a dog is suspected of being afflicted with BCM, the wearing of a Holter monitor to track its heart rhythm for a 24-hour period is advocated. But canine cardiologists studying the Boxer differ, sometimes markedly, in their judgment of just how many abnormal beats (PVCs) indicate a pathological condition -- two? 20? 200? 2,000? I have been told that one is too many and that anything greater than 10 is highly suspicious. I have had equally dedicated and eminent cardiologists tell me that the healthy Boxer may entertain many more single PVCs than that (that are not in runs) and be "normal"-- whatever that is. I have also been informed that 24-hour Holter tracings may differ markedly in the same dog from one day to the next and that a normal Holter in a given dog can be decidedly abnormal a year, six months or two weeks later.

Unfortunately, we have yet to establish sound medical guidelines to determine testing protocols for these conditions. Although testing for SAS is more reliable in that the absence of a murmur and a low blood velocity probably clears an animal, there is the question of the age at which this test should be done to make sure that the individual really is clear. Likewise, questions exist regarding testing for BCM: What is a "normal" Holter for a puppy? For a 2-year-old? A 6-year-old? A 10-year-old? Are dogs "allowed" more PVCs with age, or does it not matter? Is the 10-year-old that develops BCM any more (or less) likely to pass it on than an afflicted 2-year-old? (Evidence suggests that both dogs suffer from the same problem, but there was more significant genetic penetrance in the young animal.) If the 10-year-old passed it on during his long breeding career, should we automatically eliminate his offspring from our gene pool, even if they test normal?

In short, there are a host of unanswered questions. If the OFA will not certify a dog as being free of hip dysplasia until it has reached 2 years, it is clear that we need similar guidelines to evaluate the devastating heart ailments that take many of our Boxers before their time. In the meantime, I think the fancy should take a deep breath and avoid medical evangelism on the Internet and elsewhere. If some breeders take a skeptic’s view of the current state of testing, it does not mean they don’t care. They may honestly believe that the results of current testing methods are not sufficiently meaningful in the asymptomatic Boxer. Such breeders may be right or may be wrong, but if they love their dogs, as most of us do, they are likely not to be at all indifferent. Let us hope that one day, sooner than we expect, research into genetic markers will allow us to positively identify these potentially devastating cardiac conditions. Then, simple blood tests may enable us to avoid a host of disappointments and no few tears.

Drs. John-Karl Goodwin and Kathryn Meurs are recipients of grants from the AKC Canine Health Foundation that will enable them to study heritable patterns in Boxer cardiomyopathy. (The grant includes funds donated by the American Boxer Club Charitable Trust.) It is hoped that gene mapping will result from this project so that BCM can be identified at an early age.