Liver, Heart and Adrenal Weights of Broilers Reared Under Constant Temperatures

GARREN and Shaffner (1952, 1956) exposed New Hampshire chicks to 6.7°C. for periods up to 4 weeks starting at 7 weeks of age and found the adrenals larger and the bursa and spleen smaller than in birds at room temperature. Wolford and Ringer (1962) used Single Comb White Leghorn hens and exposed them to 1.7°C. for short periods and concluded that adrenal weights appear to be unreliable as stress indicators in the mature hens. Francis et al. (1967) reared three strains of Single Comb White Leghorn males at 15, 182 and 2,215 meters above sea level and concluded this significantly affected relative heart weight. A study was conducted to determine the development of broilers reared under various constant temperatures from 1 to 56 days of age as measured by liver, heart, and adrenal weights. EXPERIMENTAL PROCEDURE Immediately after hatching, 120 commercial broiler chicks were placed in each of four environmental…