Thermoneutral Zone (TNZ): The range of external ambient temperatures in which a healthy animal can maintain a normal core body temperature (Das et al., 2016) 

Das, R., Sailo, L., Verma, N., Bharti, P., Saikia, J., Imtiwati, & Kumar, R. (2016). Impact of heat stress on health and performance of dairy animals: A review. Veterinary World, 9(3), 260-268. https://doi.org/10.14202/vetworld.2016.260-268