The course lays out basic understanding with regard to the effects of the ambient environment on farm animal physiological performance. This environment is composed of several micro- and macro-climatic components. Individual and combined changes in these components elicit various physiological reactions to maintain regain homeostasis. Environmental extremes challenge the well-being and performance of farm animals ? primarily kept as food source -, and hence can impact man due to the potential depreciation in animal productivity, and eventually economical outcome from the animal agriculture business sector, which contributes in varying degrees to national and international food security and well-being of the human population.