After writing about the virtues of dog racing the other day, I have been bombarded with letters and propaganda from animal lovers denouncing the cruelty of the sport.

The Humane Society, the Fund for Animals and other such organizations have been waging a vigorous campaign against dog racing, which would be legalized in Washington if voters pass a referendum May 6.

These groups object not to the sport per se, but to the way they say greyhounds are trained. Their literature makes "The Texas Chainsaw Massacre" look like kids' stuff: "Its eyes bulging, its chest pounding, the rabbit bleats as it watches its killers in pursuit." One flyer juxtaposes a picture of tots cuddling a loveable bunny with a photo of a pile of rabbits who had been torn apart by greyhounds.

This campaign has been extremely effective. It has taken the issue of legalized gambling -- which ought to involve a lot of serious social, political and economic questions -- and made it into the issue: Do you favor torturing the Easter Bunny?

Some of the antidog racing propaganda is wildly exaggerated and misleading. Perhaps there is a demented trainer who lets dogs tear apart helpless kittens, or who locks a dog into a cage with a rabbit and deprives him of food and water to turn him into a crazed killer. But responsible greyhound trainers would deplore (and question the intelligence of) such methods as much as the Humane Society does.

The principal objection of animal lovers to the sport is well-founded, though. Greyhounds do often train by chasing and killing live rabbits.

These rabbits bear about as much resemblance to Peter Cottontail as big-city sewer rats do to Mickey Mouse.

"In the southwest," said Gary Gucchione, assistant secretary of the National Greyhound Association, "wild jackrabbits are considered a menace the way rats are in the big cities. They can move into a farm and eat their weight in a matter of a few days. That's why the greyhound was brought here in the first place: to kill them. The greyhound was a godsend to the farmer."

The only good jackrabbit is a dead jackrabbit. They have no redeeming social virtues; they can't be made into pets; they don't even make a tolerable rabbit stew. The well-being of these creatures would hardly seem to be a burning social issue (though judging from my mail, there are several people who think otherwise).

Dogs who show aptitude in their early training and enter actual competition at the race track are treated very well during the careers (better, in some ways, than horses). But the ones who don't have sufficient ability often are killed.

Opponents of dog racing tend to depict this as the work of demented sadists, but the people who breed, train and race greyhounds are usually dog lovers themselves. They do not inflict wanton, senseless punishment on their animals. But they know that greyhounds have been bred over the centuries to do just one thing -- run fast -- and if they can't do that they are useless for anything else. Few people adopt them as pets. So they are, in the popular euphemism, put to sleep.

The greyhounds who do race make possible an industry which provides thousands of jobs, gives considerable entertainment to thousands of people, and which in the state of Florida alone raised $60 million in tax revenue last year.

Passionate dog lovers, who consider the sanctity of animal life more important than the quality of human life, may not consider the benefits of the sport important. I do -- but then, I'm not a dog lover. The only time I consider a dog to be man's best friend is when he pushes his little nose across the finish line and brings home a $100 exacta.