Definition of a Controlled Environment

Definition of a Controlled Environment

An environment is described as the surroundings, conditions or influences that affect an organism (Davis, 1989). A control acts in modifying the behavior of a system so it behaves in a specific desirable way over time. Implying control on an environment requires managing the impact of certain factors on a system. A controlled environment therefore regulates the effect of environmental factors in a system.

The response of animals to environmental challenges is important and applies to all species (Lara and Rostagno, 2013). In animal agriculture, the issue of environmental stress is now of vital interest (; Olanrewau et. al., 2010; Lara and Rostagno, 2013; Singh et al., 2014 ). Ways to mitigate the effects of environmental stress to the production of livestock and poultry animals are fundamental in increasing food supply and the practice of integrating environmental control in livestock and poultry systems by controlling environmental conditions is crucial under the spontaneous effects of climate change and the shifting weather conditions in the country.

On the impact of climate chajnge in the Philippines, Asian Development Bank (2011) proves that lower livestock and poultry production are likely to result from excess heat and drought in some places. Reproduction in farm animals is highly affected by environmental factors and when environmental conditions are favorable, reproductive activity expresses its full potential (Singh, et al., 2014).  

Olanrewaju, et al. (2010), says that achieving high productivity through genetic potential, the theoretical optimum performance capability of genetically selected breeds of poultry will not be fully realized until microenvironmental constraints (temperature, humidity, light intensity, air velocity, etc) have been fully addressed.

Additinally, when temperatures are raised between 6OF and 7OF (~15C to 24C) the most rapid gains in production occur in pigs. Feed efficiencies were also greatest in this temperature range and as temperatures were reduced, greater amounts of feed were consumed (Bond, 1958; Hazen and Mangold, 1960; Bell, et al., 1964; Mangold, et al., 1965).  The use of "effective temperature" as a means of evaluating swine environments is also being studied upon as an effort to relate the effect of relative humidity and temperature to the growth rate of swine. (Beckett, 1964; Morrison, et al., 1966).

On the other hand, Hirning (1970), pointed out that though research information concerning desirable environmental characteristics for optimum performance of beef animals is quite limited as these animals requires less environmental control, it is found that beef cattle performance in the feedlot improves when shade is provided and temperatures above 7OF (~15C) gives heat stress that affects performance of beef (Ittner, et al., 1958; Morrison, et al., 1968).

The main natural physical environmental factors affecting livestock and poultry include air temperature, relative humidity, radiant heat, precipitation, atmospheric pressure, UV-light, wind velocity and dust (Folk, 1974). In a controlled environment, these factors must be work upon.