Theoretical comparisons of energy inputs of farm-animal husbandry systems

The farm-animal husbandry systems are based on energy inputs in order to secure their productivity. The farm systems, which produce concentrates and hay, support the animal husbandry systems but they also need energy inputs. These inputs include the energy for machinery manufacturing and their field operation to produce animal foodstuff. This study investigates the energy inputs of farm systems and animal husbandry systems of different intensification. Based on the energy inputs to produce animal foodstuff and grass from leys and rangelands, four different sheep-raising systems are evaluated (numbers in parenthesis are energy inputs in MJ sheep-1 year-1: stable (1556), semi-stable (1661), pastoral-unimproved range (1391) and pastoral-improved range (1305). These numbers can be used only for comparison purposes and have not absolute value. The energy inputs estimation of these systems has economic and environmental importance (e.g. consumption of nonrenewable energy resources, climatic change). Thus it would be important to be taken into consideration in planning agricultural sector policies.