Dr. Lee explains the research being carried out by the U.S. Dept. of Agriculture's Dairy Husbandry Research Branch on milk production in tropical climates. He says that of the two major milk cow groups, the European cattle offer high milk production but low resistance to a hot environment and the native Indian humped cattle are the opposite. In addition to breeding the most heat resistant European cows and selecting the native cattle with the highest milk production for breeding, the Dept. of Agriculture is cross breeding Jersey cows and Sindhi cows. The research results seem to show that a cow that is 5/8 native Sindhi has the best combination of heat tolerance and milk production. In a film of the heat room, Mr. McDowell explains experiments which measure the cows' sweat and their respiratory cooling. He also notes that the color and thickness of a cow's coat and its blood flow to the skin are possible determinants in heat adaptation.