12.3 Energy Balance

Assuming that an animal’s body temperature is constant (steady state), energy input to the animals must equal energy out. We can write the animal’s energy balance as follows: \[\begin{equation} M + R_+ = R_- + C + H + E \tag{12.1} \end{equation}\] where \(M\) is the metabolic rate, \(R_+\) is the amount of radiation absorbed by the animal surface, \(R_-\) is the thermal radiation emitted from the animal surface, \(C\) is the heat conducted from the animal to any surface it is in contact with, \(H\) is the heat loss from the animal to the environment via convection, and E is evaporative heat loss.