Optimal thermal conditions for farm animals are crucial preconditions for development of improved climate control methods. Both low and high temperatures are known to comprise both daily gain and feed efficiency. The
aim of this work was to utilized published studies to determine how the ambient temperature affects the daily gain and the feed efficiency for finisher pigs. Literature assessing daily gain and feed efficiency at different ambient
temperatures was gathered using Cab Abstract and Google Scholar. The results were transformed to relative values with 100% being the temperature at which the highest productivity, in that particular study, was found. The slope
corresponding to each degree Celsius was calculated within the temperature range investigated in the in the particular study. The mean slope values for all studies were calculated and the average response was illustrated in
a graph. Results showed that the two productivity parameters did not peak at same ambient temperature. The daily gain peaked at 15°C and was above 95% of its maximum between 10 and 21°C. Feed efficiency peaked at 23°C and was above 95% of its maximum between 17 and 29°C. The optimal ambient temperature for finisher pigs was
found in the range between 15°C and 23°C. For the individual farmer, the economic optimal temperature is
dependent on feed costs, energy costs, and on whether additional pigs are available to utilize the housing capacity
gained by increased grow rate. In the latter case, the optimal temperature will be lower than if the faster growth
causes a reduced utilization of the housing system.