Animal pens are enclosures for housing animals that can be easily observed, monitored, and cleaned. They are a vital piece of any animal facility. Pens are often used for nutritional trials and make it easy for staff to observe animal behavior, take health and water intake data, dispense feed, and collect refusals. They also facilitate the collection of feces and urine samples. The size of a pen should be determined by the number of animals to be housed in it at a time and should provide adequate room for each individual animal to move and lie down comfortably. Insufficient space can reduce the productivity of livestock and may be a predisposing factor to infectious disease.

Inadequate housing and ventilation, overcrowding, and discomfort are thought to contribute more to the losses of livestock from disease than do infectious diseases. The adequacy of the air exchange in barns filled to economic capacity should be assessed by measurement of the number of air changes per hour, the humidity during the day and night, the vapor pressure of ammonia and hydrogen sulfide, the location of exhaust fans, building and insulation materials, and the nature of partitions between pens.

Optimizing Animal Pens: Flooring Considerations for Safety and Comfort

Active composting of bedding and manure from animal pens can be accelerated by turning the piles regularly. This physically fragments the manure, simulates saprophytic microbial activity, and mixes fresh bedding with old manure and feces. Another method to accelerate the process is to add a bulking agent (e.g., straw or peat), install a plenum to increase aeration, inoculate the pile with desirable microflora and fauna, and add C-rich or nutrient-rich substrates.