Thousands of chickens in the poultry producing areas of Maryland and Virginia have died of heat prostration during the recent series of hot, muggy summer days.

Cooped up in large chicken barns, thousands of these birds crowded together "plop over and die," according to growers when temperatures in the buildings rise into the upper 90s.

"There isn't a thing we can do, except change the weather," said one frustrated Maryland poultry producer --chicken coops -- some housing 10,000 chickens -- have fans, but the heat and humidity are too much for the crowded birds.

Chicken producers say, however, the thousands of fatalities will not put a dent in the chicken market because their yearly chicken production reaches up not the million.

These chicken producers, who refer to their product as "roasters" and "broikers" say the roasters which are heavier and older -- are particularly susceptible to the heat.

Maryland, Perdue Inc., near Salisbury, has lost approximately 30,000 roasters as direct result of the recent heat wave, said spokesman Tom Shelton.

The largest chicken producer in Shelton said the 30,000 dead roasters valued at $2 a piece and the hundreds of dead broilers valued at $1 a pience, would harldy affect the company that each year sells more than 78 million chickens and grosses more than $150 million.

For other producers, getting specifics on their losses is difficult due to the industry's competitiveness.

At Holly Farms, also located on Maryland's Eastern Shore, the losses of broilers range up into the "thousands" said a spokesman.

The broilers, according to the spokesman, are fed with a special feed that increases their weight rapidly and makes them vulnerable to the heat because their young legs are already wobbling under their artificially induced weight. He said the intense heat causes them to just "plop over and die."

"It started around July 4th," said Jesse Gibbs of Holly Farms, who said the chicken deaths multiplied in the next weeks as the temperatures continued to soar.This happens normally in very hot summers.

He said the chickens, confined to one square foot each would die when the fans failed to produce enough air in the huge chicken barn.

After the chickens die, said one pultry producing spokesman they are either buried or taken to a pultry rendering plant where their remains are used for chicken feed.

A spokesman at Rocco Chickens and Hatchery farms in Virginia said: "The houses are a little tight. . . and the fans can't take the heat."

He said one of the company's poultry producing farmers had returned to his barn during one of the recent seltering summer days and found 200 boilers dead.

These chicken raisers, which are among the nation's top five, say chicken deaths are even worse in the South.