Abstract STUDIES by Barrott and Pringle (1949, 1950), Ota and Garver (1954), Prince et al. (1960) and Howes et al. (1962) indicated that the optimum environmental temperature for growing broilers decreased to approximately 12.8° to 18.3° at 4 to 5 weeks of age. Some controversy exists in the literature concerning density effects on broiler performance. Tomhave and Seeger (1945), Mehrhof and O’Steen (1948), Heishman et al. (1952), Thayer et al. (1953), Hartung (1955), Brooks et al. (1957, 1958), Milligan et al. (1957), McHenry (1958), and Hanson and Becker (1960) reported a reduction in growth rate as floor area per bird was decreased. Siegel and Coles (1958), compared 0.50, 0.75, 1.00, and 1.25 square feet of floor space per broiler and found little difference in body weight. Olinde et al. (1965) used bird densities of 0.50, 0.67, and 1.00 square feet of floor space under fogging and non-fogging conditions. Fogging of broilers . . .