Robert Baker's career as a stockbroker changed after he looked behind a racetrack.

With idle mornings in the mid-1970s, Baker went backstretch for the first time to work with the five horses he owned at Cahokia Downs, a small Illinois track now defunct. He began appropriately -- cleaning their stalls, grooming them, walking them -- before the learning process shifted course.

Baker said he saw a horse beaten with a two-by-four before a race to incite him. He said he saw an injured horse, incapable of racing, receive no food or water for days. He said he saw a "million-dollar horse" kicked upon refusing to board a van, the animal falling off a ramp and onto gravel.

"Some of the horses were so crippled up and lame, yet they'd give them enough Bute {phenylbutazone} to race them," Baker said. "I'd see them the next day lying in their stalls because they were so sore.

"My initial reaction was: 'This must just be happening at these cheap tracks,' but I found out it was occurring all over. People at the cheap tracks would say, 'We're not the Whitneys; this is our livelihood. We have to drug our horses.' I'd talk to rich people and they would say, 'This is a $50,000 race. Do you know what the stud fees are going to be if he wins?' This thing really upset me. All across the line, people were drugging horses, doing it legally and having a rationale for doing it."

Baker spent years lobbying against racehorse abuse and in 1980 made it his livelihood. Today he is a senior investigator for the Humane Society of the United States. Spotlight on a Tragedy

Go for Wand's dramatic breakdown and subsequent destruction at the Breeders' Cup Distaff at Belmont Park on Oct. 27 gripped hardened and inexperienced race-watchers alike, sparking a nationwide public outcry. Horsemen and fans criticized NBC's replaying of the champion filly's fall. Sports Illustrated received volumes of letters after publishing a series of graphic photos of the incident.

"The $1 million paydays, breeding fees and {stallion} syndication are why the animals are bred; their welfare is the last concern," read part of a letter published in The Washington Post. "This is sport?"

Baker says racehorses get too much medication, too little care and race too young. But in a number of interviews, people in the thoroughbred racing industry defended the means by which horses are treated and maintained, saying overall care is excellent. Livelihoods, they say, depend on it.

"I spent three years in show-horse practice, and I saw much more cruelty and ignorance than I've ever seen at the racetrack," said Pat Brackett, one of several state-represented veterinarians who oversee the on-track welfare of horses who race in Maryland. "Horses are well-cared-for here. They get the best feed; they're clean, healthy and well-groomed. Trainers try to keep their horses happy because happy horses win races. Now you'll get some grooms from time to time who . . . can be kind of rough with them, but I think they have a good life."

Few within the industry deny that occasional abuses occur, the inescapable result of gearing a horse to man's needs. Half-ton animals with intimidating strength and iron wills have frustrated more than one stablehand or trainer. In Maryland, it is a felony to injure a racehorse if done knowingly and willingly.

Arthur Benjamin, a horse owner and co-founder of Comvest Properties Inc., a District real estate development company, said a groom once struck one of his horses and was immediately fired. "That was an isolated instance," he said. "My horses are treated like kings and queens." In his will, Benjamin has stipulated that two broodmares, both former racehorses, receive perpetual care.

Baker says the most aggrevious problem stems from the use of phenylbutazone, a non-steroidal anti-inflammatory drug that is permissible in limited quantities in most states. "They mask the pain, they mask the swelling, they mask the heat that allows full motion of the joint," he said. "We feel they're probably more dangerous than the narcotics being used."

His claim that private veterinarians have economic incentives to medicate horses drew a sharp rebuke from Jim Stewart, a veterinarian who has spent the past 20 years treating horses at Maryland's racetracks.

"Our job is to have these animals perform at their best, or effectively, for as long as is possible and safe," Stewart said. "I honestly and truly don't work for anyone who sends horses out with no regard as to whether he'll come back."

Stewart, whose practice tends to hundreds of thoroughbreds, calls Bute "a maligned drug," saying it can be both an inexpensive and effective means of reducing inflammation. "The idea that we are getting rich off of Bute is ridiculous," he said. The practice charges 15 cents for a tablet of Bute; the drug also can be administered orally in a paste or intramuscularly, both of which are more costly.

The use of Bute is among the acceptable methods that help keep racehorses performing and earning purse money. Horses who incur respiratory bleeding through exertion receive Lasix -- in Maryland, about 80 percent of older horses race with the diuretic. Horses frequently are "tapped," synovial fluid extracted from a joint and replaced with a lubricant. Some may be "blistered," in which a leg painted with a caustic material heats and swells, promoting healing. "It's terribly painful," one trainer said.

Some horses are stood in ice for hours, or with a cold hose fixed on a leg. They're confined to stiflingly hot stalls in summer, run on frozen tracks in winter, and even the fastest are whipped to go faster.

In the end, it all comes down to money.

"It would be great to run horses who are totally sound," said trainer John Hartsell. "But the economic demands put pressure on the owner, who puts pressure on the trainer, who puts pressure on the horse."

Throughout backstretches across America, horsemen balance health and wealth every day. Stewart says he will advise a trainer or owner whether to run an unsound horse, but the choice lies with them. "I have made mistakes, but I have not done it purposefully or with knowledge that great risk was at hand," he said. "To do my job well, I have to make a judgment as to whether it's safe to run one more time. If I {allow horses to race} that break down and fall apart, I'll be out of work in a heartbeat. On the other hand, it's not in my best interests to be overly timid. People will stop using me."

"If a horse isn't doing well, a trainer might try to get one or two more {races} out of him; or if he's unsound, he may take a big drop in class," said R. Richards Rolapp, president of the American Horse Council and a small-scale owner and breeder. "But the overall objective of the industry is to race sound horses, to breed sound horses, and not to abuse them."

It is estimated that fewer than 1 percent of all thoroughbreds die from racing related injuries. Go for Wand was graphic proof that even the most talented are not exempt.

Joe Pons had more than a casual interest in seeing Go for Wand prosper. Her half-brother, Carnivalay, stands at stud at Pons's Country Life Farm in Bel Air, Md.

Pons watched in horror as Go for Wand strained to get a neck in front of Bayakoa well into the Belmont stretch, then snapped an ankle and fell a moment later. Ultimately he was able to rationalize it, as anyone who lives within the industry must.

"It's been bred in horses for thousands of years to do their best and to die for what they were perfected to do," he said. "Horses don't know how to protect themselves; they'll keep putting out until it kills them. You've got an eleven-hundred-pound animal with someone on his back, and he's tired and fighting . . . it's surprising more of 'em don't break down.

"The horse is such an exquisite animal, and it gives its all at the expense of its life. Unfortunately, there are lots of {people} in the game who don't care about the horses, just as there are doctors who are abortionists and lawyers who are crooked lawyers. The fact that horses run on Lasix and Bute is overpublicized. Football players take painkillers. America is based on drugs." Rigors of Nonstop Racing

Pons and other breeders believe that lingering infirmities are caused more by year-round racing than by genetics. David Hayden, who bred Maryland's most successful filly ever, the champion sprinter Safely Kept, said, "In the old days, horses had time to go home, and that would serve as its own form of therapy. But now more than ever, it's a capital-intensive business, and you need to develop cash flow. I don't think it's a sport any longer for the masses. People like the Phippses may call it sport, but when you're knocking down the numbers they are, it's business.

"If you want to play {as a breeder} you have to accept the fact that you no longer have control once they leave your hands."

Once horses get to the track, Baker says, they're subject to various forms of abuse that go unrecognized within the well-insulated racing industry. He said he attempted to have Ben Feliciano prosecuted on an animal cruelty charge in 1988 after the former jockey blinded a filly when he struck her in the head with his whip. Zeus Belle's right blinker -- a plastic cup that restricts peripheral vision and helps keep a horse focused -- shattered and a fragment pierced her eye. Feliciano claimed the incident was accidental; he was fined by the Pimlico stewards.

Baker said he reconsidered prosecution after the stewards said they would support Feliciano. Zeus Belle never regained vision but raced -- and won -- with a plastic bubble over the eye.

"You can get away with practically anything on the backstretch as far as being cruel to a horse," Baker said. "Anti-cruelty laws are largely unenforceable on the racetrack. When it comes right down to it, bettors don't care what happens to a horse beyond winning and losing. They're interested only in their bottom line. They {racetracks} muddle through every scandal because they have a base of people who will always come to bet."

Wayne W. Wright sees it differently. The executive secretary of the Maryland Thoroughbred Horsemen's Association says racing in Maryland alone furnishes thousands of jobs and brings the state millions of dollars in revenue. "In racing, you need the horse and you need the fans; everyone else falls in between," he said. "It's absolutely ludicrous even to insinuate that horsemen do anything but offer their animals the best of care."

"I've been in this game 52 years; I think my horses {have} been cared for as good as any that ever existed," said trainer John Lenzini. "I've fired and fired and fired people who haven't treated them right. Help is bad. I don't care if you run a gas station, a supermarket -- if there's one employer satisfied with his help today, he's very lucky.

"This is our living. The only way we do good is by our horses doing good. I'm at the barn at 5:15 every morning. How can you say people like me treat horses bad? If I wanted to treat them bad, I'd leave them in the barn and not show up seven days a week. You're always gonna find a person that's brutal to a horse. For the majority of people, why would they hurt something that's making them a living?"

Baker countered, "That horse is only valuable if it's racing. It's not valuable when it's being laid up. Therefore the incentives are not to be giving care all the time."

Baker said he believes that racing 2-year-olds places undue stress on young thoroughbreds who are not fully grown, but horsemen said the Kentucky Derby and other major races for 3-year-olds make it unavoidable. C. Fred Kohler, a Virginia breeder the past 30 years, said he prefers not to run horses until late in their 2-year-old seasons because they're more prone to injuries.

Not everyone in the industry operates completely without misgivings. One trainer said, "The whole thing bothers me. It wouldn't bother me so much if people had a little compassion for these living, breathing animals. This summer, the guilt was getting to me. I was making money, and horses were standing in 100-degree stalls, flies everywhere. I thought, 'What kind of life is that?' But not a lot of trainers think like that."