Energy

Without energy, nothing moves. Not even inside the body. But not only visible physical movement costs the body energy — all other functions do as well, such as cardiac performance, respiration, all digestive processes, brain functions, etc. This is why a distinction is made between energy for maintenance requirements (the functions mentioned above) and performance requirements for physical work. Energy must be supplied to the body through feed. Feeds contain more or less digestible and utilisable energy. Metabolic energy (ME), also known as metabolisable energy, refers to the utilisable amount of energy available to an animal from a feed. It is stated in MJ/kg (megajoules per kilogram). It is calculated from gross energy minus energy losses through faeces, urine and intestinal gases. Until 2014, the relevant energy measure in horse feeding was DE (digestible energy), which did not account for losses through urine and intestinal gases.

For more on energy values, see also our specialist article: How much utilisable energy is in horse feed?