Science: Air-Cooled Cows

After a pampered passage from India, four “Red Sindhi” cattle—two bulls, two cows—chewed their cuds last week in a New Jersey cow barn. They were the first Indian cattle to enter the U.S. since 1924. When sufficiently rested from a plane-ship-plane journey, they would start a major breeding project: begetting cows to bulge with milk on the humid, hot Gulf Coast.

U.S. dairy cattle neither thrive nor give much milk in damp, semitropical climates. In Florida and Louisiana, the milk flow of Jerseys, Guernseys and other familiar breeds falls off as much as 40%.

Their chief difficulty with these breeds seems to be lack of built-in air conditioning. Cattle have no sweat glands. On hot days, they cool themselves by the energy-consuming process of breathing hard and evaporating moisture from their lungs. When the temperature goes above 95°, they run a two-degree fever. Instead of grazing in the broiling Southern sun, they prefer to stand idly in the shade and go hungry.

Heat-proof Bos. Indian cattle, descended from the tropical Bos indicus instead of from the European Bos taurus, are better cooled. Their loose, hanging skins give them more cooling surface. Their hides are thick, and their hair is an efficient insulator.

“Red Sindhis” are among the best milch cattle in India, although their production, averaging 2,000 Ibs. a year, is poor by U.S. standards (5,800 Ibs. average). But the Bureau of Animal Industry hopes to develop eventually a Sindhi-Jersey cross which will combine good milking qualities with ability to thrive and flourish in hot climates.

Such a breed might bring new prosperity to Southern farming, victim of a dying cotton economy. It might also improve the diet and health of near-milkless Latin American neighbors.