Fig. 1From: Methodologies on estimating the energy requirements for maintenance and determining the net energy contents of feed ingredients in swine: a review of recent workScheme of energy utilization in pigs. The utilization of energy in a feed by pigs is a multi-level system. GE, gross energy; DE, digestible energy; ME, metabolizable energy; RE, retained energy; NE, net energy; FE, fecal energy; UE, urinary energy, THP, total heat production; FHP, fasting heat production; HI, heat incrementBack to article page