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When animals are free ranging “dilution is the solution to pollution.” Animals that range freely tend to distribute their waste over a large area and the natural processes disseminate the waste. When animals are confined the waste is concentrated in one spot and it becomes part of the management of the animals. Animal waste management is no longer an option in a livestock business; it is a requirement. A plan for the collection and disposal of animal waste must be part of any livestock facilities plan. Failure to provide adequate waste management collection and storage facilities, and disposal equipment can lead to pollution problems with legal complications, animal health problems, increased production costs, and a generally undesirable working conditions. In most states, confinement operations must have a comprehensive nutrient management plan. There are three aspects of animal waste management:

All living organisms have a preferred environment. Whenever the environment is not within the preferred parameters, the organism is stressed. Stress can reduce productivity, increase the incidents of illness, shorten the storage live of products and cause many other problems. In the natural environment, organism modify their environment by moving from one location to another. Once animals and other organisms are confined, they cannot roam, and the environment must be modified to meet their needs. Two ways environments are modified are heating and cooling.

Air is a complex mixture of gases, water vapor, and heat. All living organisms require these three components, but not necessarily in the same proportions. Each organism has an optimum range of all three conditions, and any time the conditions are less than optimum, the organism is stressed. Management of these components may be critical within agricultural structures. Heating, cooling, and ventilation are used to modify the natural environment to reduce the environmental stress of animals and biological products.

A beam is a horizontal member used to support a load. The design of structural members for a particular load involves analysis of the forces imposed on the member by loading and selection of appropriate materials, shapes, and sizes to accommodate the loads. This procedure is best accomplished by a structural engineer and is beyond the scope of this book. Failure to use a beam of adequate size can lead to beam failure with the accompanying danger of injury and/or financial loss. However, several basic concepts are presented here to help the reader understand the properties and load-carrying abilities of simple and cantilever beams made of wood.

Agricultural production depends heavily upon electrical energy to power machines, lights, equipment, and tools used in producing and processing agricultural products. An understanding of the principles of electricity will lead to more efficient use of electricity and reduce the risks associated with working with and around electricity.

The purpose of electrical circuits is to supply electricity for an appliance, tool, or other type of electrical device. These devices are called loads. Before the load will operate, electricity must have a complete path from the source to the load and back to the source. This path for electricity is called a circuit. Two types of circuits are commonly used to supply electrical power, series and parallel.

Conductors are used to provide a path for electricity. The metals used for conductors have a relatively low resistance, but they have enough resistance to cause a voltage drop when current passes through them. If the wires are overloaded, the voltage drop increases, causing a reduction in the efficiency of the circuit and an increase in the heat produced. Heating the conductors above their designed operating temperatures will cause the insulation to fail, and the heat generated can be sufficient to start a fire if flammable materials are close.

An electric motor is a machine that converts electrical energy to mechanical power. Modern agriculture is heavily dependent on the use of electric motors. Managers of agricultural production systems should know the common types of motors and be able to select the correct motor. Manufacturers have gone to great lengths to design motors to meet the needs of agriculture. The life of an electric motor is determined by how well the motor is matched to the job and the service environment. The following sections will discuss the characteristics and uses of 120/240-V, single phase motors.