EN: ON BONE CANCER IN GREYHOUNDS

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EN: ON BONE CANCER IN GREYHOUNDS

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ON BONE CANCER IN GREYHOUNDS

It seems that every week or so, someone in a greyhound discussion group asks about bone cancers in NGA Greyhounds. The implication of some of the less greyhound-informed---as various breeders, breed professionals, enthusiasts and novices, with even an occasional veterinarian or assistant adding their considerable wisdom, often to the contrary---is that the various bone cancers which afflict most large and long-limbed breeds, can somehow be "bred out" of the population. No one, despite the considerable efforts of modern, veterinary science, has discovered any magic bullet that might help to accomplish what would be this most daunting and painstaking of tasks.

Not being anything close to an expert the on bone cancers to which greyhounds are sometimes subject, I usually butt-out of such conversations, which are almost always dominated by those who are equally unqualified to speak authoritatively on the extremely complex and vexing science of the matters at hand, anyway. My infrequent contributions to the subject come only from my experience with, and observation of greyhounds, the long-time study of and fascination with greyhound bloodlines, and their cause and effect upon the greater population of them.

Having arisen from a discussion of that very subject, the following may help explain the current state of the greyhound population in America. and the corner into which the greyhound finds himself having been backed, as the population continues to diminish, likely to eventual, fringe-breed status.

I began by asking if anyone might care to take a stab at identifying which domestic, greyhound bloodlines are free of the genetics that cause bone cancer. I suggested that such research might begin with the female families (that's the bottom line of the pedigree), and asked that if anybody happened to discover one, that they please PM me with the germane info.

Traditionally, the US greyhound breeder of track dogs, has preferred the "outcross" to inbreeding. To explain, our greyhounds, for well over a century, have been the beneficiaries of several massive waves of imported sires and dams, from Australia, the UK, and Ireland, which has made them uniquely diverse, genetically.

They are, as a population, the least "inbred" population of the major greyhound-breeding countries.The genetics of the iconic breed-shapers, from every greyhound-mecca, and from every era, as a result, are very well distributed throughout the US greyhound population. This embrace of "outcross" breeding strategies, looking back on it, in the current state of extreme population loss, has been, perhaps, a double-edged sword. I don't think anyone from the bygone century, even in their most fervent moments of clairvoyance, might have foreseen the current, ongoing decimation of uniquely American, greyhound bloodlines.

Back in the day before frozen semen, local sires were in great demand. There were dozens of local sires in racing states, whose strike rates were just as good or better than the more fashionable, popular sires. Some of these sires were from relatively more obscure and/or less fashionable bloodlines, which were often privately kept, and seldom sold or shared, until a viable sire emerged.

There was quite a bit more competitively viable and available genetic diversity as a result. And since successful imported sires were lionized at levels we have not seen since the 1960s and 70s (and every decade before that, in the track era), the bloodline mix was even more diverse. We haven't had anything close to a prepotent and breed-shaping, import sire in the US, since the 1990 whelp, Fortress. (with all due respect to the Australian Brett Lee, who did produce 3 viable sires from only a relative handful of matings here.)

The feedback that breeders use to guide their breeding decisions comes from athletic performance, and not from post-racing life, (when most bone cancer manifests). That is the only way one can operate and hope to have a successful breeding program of performance greyhounds, given the crushing expenses of supporting even a small colony of greyhounds, the intense nature of the competition---and the fact that mere nano-seconds are what separate a world-class greyhound from a dozy, sofa-ornament.

Breeders have very little wiggle-room in matching their competitors, stride for stride, in such a dramatically reduced breeding population, with drastically diminished racing opportunity, and with fewer and fewer, and less and less diverse, viable breeding choices. Not if they wish to remain breeders.

Nevertheless, there seems to be quite a bit more unknown than what is known about bone cancer in greyhounds, other than that the genetics of it appear to be extremely widespread throughout the population. As the population diminishes exponentially---as in "now"----any chance of "breeding out" of this thing (which we have not entirely identified at any rate), becomes less and less realistic, if that ever were the case at all.

As the breed continues to be further diminished, and the population shrinks to unprecedented, genetically less-diverse levels, in the absence of a macro-program of regulated and structured performance ---featuring head-to-head competition and comparative, empirical and statistical feedbacks that breeders can use to analyze and aid their selective process---we might do well to remember that the NGA greyhound is, at this stage of his evolution, still kept virtually free of the crippling, genetic defects of hip and elbow dysplasia, patellar subluxation, and other heritable, degenerative diseases that compromise structure and soundness, and cause untold suffering and death in so many other breeds.

Embrace it while you are still able.

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Nur wer einmal seinen Windhund jagen gesehen hat, der weiß, was er an der Leine hat!
Michaela
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