Thermoregulation in piglets: environmental and metabolic consequences

Abstract At birth the neonate switches from a dependent to a totally independent extra-uterine environment. It must begin to regulate its own body temperature to survive. This paper considers thermoregulation in the newborn piglet and those factors which influence survival. The first few days are important for the development of thermoregulation. Metabolic heat production and rectal temperature both increase and the development of adequate thermal insulation helps to withstand the effects of a cold environment. The body reserves play an important rôle and are needed to ensure that the piglet survives within the first hours of life. It is the glycogen and fat reserves that are readily utilized as major energy substrates for heat production within the first 12 to 24 h; the contribution from protein is minimal. However, not all reserves are available for mobilization. Attempts to improve the body reserves of piglets have been unsuccessful but the quality and composition of colostrum, especially its fat content, can be manipulated by maternal nutrition. Coldness impairs the development of thermostability and induces hypothermia. This diminishes the vigour of the piglet and reduces colostrum intake and hence immunoglobulins. The incidence of disease, especially scouring, may therefore be increased. The maintenance of an adequate environment also ensures a good immunological status. The development of housing, husbandry and management practices must take these various phenomena into account.