Hatching House Flies For Profit (Oct, 1939)
Hatching House Flies For Profit
IN AN ODD SKYSCRAPER FARM, DOMESTIC PESTS ARE RAISED FOR MANY CURIOUS PURPOSES
By FRANK CAPORAEL
SEVENTEEN stories above one of the busiest streets in New York City, America’s strangest livestock farm has its barns and pastures. The barns are glass jars. The pastures are mesh-inclosed cages. And, the product of this skyscraper ranch is house fliesâ€”5,500,000 flies a year!
The unique enterprise started ten years ago when scientists of an insecticide company wished to make exact tests of the effectiveness of their product. They needed normal, healthy flies on which to test the sprays. From this small beginning, the fly farm has grown to the mass-production activity of today.
Under the direction of Dr. Alfred Weed, as many as 15,000 flies a day are turned out for a wide variety of uses. The majority end their days in spraying tests conducted in the laboratory where they are born. But others are purchased for different uses. Mrs. Norman Bel Geddes, wife of the noted industrial designer, once put in several orders for flies to feed a pet chameleon. Another New York woman, who returned from Florida with a pair of tiny tree toads, called the laboratory to inquire the price of a dozen houseflies a day for her pets. During the past summer, 5,000 flies a day have been supplied for one exhibit at the New York World’s Fair.
All these insects grow up under exactly; the same conditions. Air-conditioning apparatus keeps the humidity and temperature in the glass-inclosed fly farm the same from day to day. Ordinary flies, breeding in filth, are oftentimes troubled with mites. Insects infested with these minute parasites have reduced vitality and succumb to poison sprays more easily than healthy flies. To insure uniform results, all flies used for testing insecticides have to be free from parasites.
By raising his winged livestock under carefully controlled conditions, Dr. Weed is able to produce millions of flies that meet this requirement. The adult insects, housed in mesh cages, feed upon water and milk. The eggs laid by the “breeding stock” are carefully seeded in jars filled with a mixture of bran, brewer’s yeast, malt and alfalfa.
The complete growth cycle of the fly, from egg to adult, consumes about ten days. For more than half of this time, the larvae, or maggots, feed and burrow through the mixture in the jars. Then they turn into tiny brown pupae which are collected for shipment. Mailed in cardboard tubes, they produce adult flies about three days later.