EFFECTS OF HIGH TEMPERATURE ON THE BIOLOGICAL PERFORMANCE OF GROWING PIGS D.J. FARRELL*

The physiological response by pigs to high temperature and the effects of plane of nutrition on the thermoneutral zone are discussed. Growth rate and food utilization are both influenced in the heat by age and feed intake, and less clearly by protein concentration in.the diet. Maintenance energy requirement is increased and efficiency of utilization of metabolizable energy is reduced in the heat. Carcass length is increasedbtif;eye-muscle appears to decline and therefore carcass quality at high temperatures. There is however very little data to show what dietary manipulations could be undertaken to improve biological performance in a hot environment. I