Ambient temperature is one of the major environmental factors that affect the voluntary feed intake (VFI) and metabolizable energy intake (MEI) of pigs. When pigs are exposed to above their upper critical temperature, they may reduce VFI, consequently decreasing their growth performance of pigs. To overcome insufficient energy and nutrient intake due to reduced VFI, energy- and nutrient-fortified diets are formulated considering the reduced VFI and fed to pigs. For the sufficient supply of energy and nutrients to pigs under high temperature, an accurate estimation of the VFI is crucial. Prediction models for estimating VFI or MEI of pigs under ambient temperature are available in the literature. The present study aimed to validate the accuracy of these equations using VFI data of pigs in the published papers. Based on the present validation study, previously published equations underestimated VFI and MEI of pigs and the magnitude of MEI underestimation was larger for high temperature than thermoneutral temperature. Novel equations for estimating MEI under thermoneutral or heat-stress environments have been developed based on ambient temperature and body weight of pigs.

Read the full article in the Journal of Animal Science.