BELTSVILLE -- About 80 feather-fluffing turkeys -- all toms and all white strutters -- look warily at visitors who approach their indoor coop. It's 10 birds per small pen, with wood chips on the floor and one dim light bulb eight feet above. The full-breasted birds, with purple snoods atop their heads and red caruncles beneath their beaks, are part of the federal flock at the avian physiology lab of the Department of Agriculture's research center.

As Thanksgiving approaches, the 40-week-old Beltsville toms are rare birds. They won't be having their necks sliced on processing-plant rotating blades, their innards hand eviscerated or their corpses cooked in the name of dinner-table joy. They are among the few survivors of the 240 million turkeys slaughtered this year by a $2 billion industry that has been flying high with record revenues.

USDA officials report that white meat will soon overtake red meat. More than 4 billion pounds of turkey flesh will be produced this year. Per capita consumption increased from 7.5 pounds in 1965 to 13.4 pounds in 1986.

November is when the turkey industry rejoices in its "harvest." It's also when those whose reverence for life includes refusing to eat animal remains celebrate a turkeyless but nutritious Thanksgiving. Vegetarians and animal-rights groups that raise Cain rather than support the raising of turkeys are depicted as spoilers at this family-centered holiday. They are also asked why they worry about killing turkeys when the outrage list is already long with such threats as nuclear war, famine and disease.

Start small, they sensibly reply. Live by the rules of a healthy diet and a simple morality: Don't eat anything that had a mother.

Factory farms, processing plants and retail outlets are silent partners with the USDA in the annual ritual of the turkey slaughter. It's here at Beltsville that federal researchers seemingly outsmarted Mother Nature and Father Time to produce birds that get fatter quicker and cheaper. Turkeys in the wild, or what's left of the wild after gunners blast through, reach 15 pounds maximum. A Beltsville tom tops out at 50 pounds, with females 30. If the birds were human beings, they would weigh 600 pounds and be good for nothing except tag-team wrestling.

A major advance in this fattening of birds to fatten industry coffers is what the USDA calls "selection ability for rapid genetic improvements." This is federalese for turkey stud farms. Governmental tamperers at Beltsville had long been baffled on the ways to artificially inseminate turkeys. It's done with horses, cattle or swine, but turkey semen is difficult to store.

In 1980, an answer was found in the discovery of the "Beltsville Poultry Semen Extender," a solution of salts, sugars and chemicals that prevents turkey sperm from dying too soon. Superior breeder toms can now impregnate entire flocks of hens. The discoverer of this breakthrough shared the 1987 USDA $5,000 prize as the "distinguished scientist of the year."

For unprized turkeys, the loss of a sex life is about the least of their endured cruelties. The birds, most of which are raised in three states (North Carolina, Minnesota and California) and slaughtered by a grouping of 20 large firms, subsist for less than four months in sheds packed so tightly -- three square feet to a turkey -- that flapping a wing or stretching a leg is nearly impossible.

At Beltsville, where toms live luxuriously compared with the average turkey gulag, no sunlight is allowed. The rays, explained an official, "inhibit their ability to produce high-quality semen." And the dim lights? "It keeps them from fighting and reduces mortality."

Despite stud farms, cash awards and sunlessness, nature is still not subdued. The current issue of The Animal's Agenda, a quality magazine that is The New Yorker of the animal-rights movement, reports on the suffering that meat-eaters inflict on turkeys. It may be two-way destructiveness: "Turkey meat is very likely to be infected with salmonella bacteria, which causes a sometimes fatal intestinal illness often misdiagnosed as 'the flu.' " The National Turkey Federation acknowledges the problem but says it is small. Animal's Agenda reports that "to improve the taste and texture of the meat, producers also inject the turkeys with flavorings and phosphates which may eventually enter the blood streams of humans."

That isn't much of an appetizer for next Thursday's dinner. Or is it? Many of those who decided to decrease their violence against animals were first moved by the health argument. That led to the ethical one, and soon it all made sense. The kind to give thanks for