Basic Control Mechanisms of Thermoregulatory Process in Livestock
BASIC CONTROL MECHANISMS OF THERMOREGULATORY PROCESS IN LIVESTOCK
SALAMI SAHEED AYODEJI
Introduction
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different (Wikipedia, 2012). Thermoregulation could also be referred to as the mechanisms and control systems used by the body to balance thermal inputs and thermal losses so as to maintain its core temperature nearly constant (Monique, 2002). This process is one aspect of homeostasis: a dynamic state of stability between an animal 's internal environment and its external environment (the study of such processes in zoology has been called ecophysiology or physiological ecology) (Wikipedia, 2012). If the body is unable to maintain a normal temperature and it increases significantly above normal, a condition known as hyperthermia occurs and any prolonged exposure (longer than a few hours) at this temperature without control mechanisms to bring it back to normal is tantamount to death of the animal. The opposite condition, when body temperature decreases below normal levels, is known as hypothermia. Most body heat is generated in the deep organs, especially the liver, brain, and heart, and in contraction of skeletal muscles (Guyton and Hall, 2006). Animals and humans have been able to adapt to a great diversity of climates, including hot humid and hot arid. High temperatures pose serious stresses for the animal body, placing it in great danger of injury or even death. For animals, adaptation to varying climatic conditions includes both physiological mechanisms as a byproduct of evolution,
and the conscious development of cultural adaptations (Harrison et al., 1988; Weiss and Mann, 1985). There are four avenues of heat loss: convection, conduction, radiation, and evaporation (Wikipedia, 2012). If skin temperature is greater than that of the surroundings, the body can lose heat by radiation and conduction. But if
SALAMI SAHEED AYODEJI
Introduction
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different (Wikipedia, 2012). Thermoregulation could also be referred to as the mechanisms and control systems used by the body to balance thermal inputs and thermal losses so as to maintain its core temperature nearly constant (Monique, 2002). This process is one aspect of homeostasis: a dynamic state of stability between an animal 's internal environment and its external environment (the study of such processes in zoology has been called ecophysiology or physiological ecology) (Wikipedia, 2012). If the body is unable to maintain a normal temperature and it increases significantly above normal, a condition known as hyperthermia occurs and any prolonged exposure (longer than a few hours) at this temperature without control mechanisms to bring it back to normal is tantamount to death of the animal. The opposite condition, when body temperature decreases below normal levels, is known as hypothermia. Most body heat is generated in the deep organs, especially the liver, brain, and heart, and in contraction of skeletal muscles (Guyton and Hall, 2006). Animals and humans have been able to adapt to a great diversity of climates, including hot humid and hot arid. High temperatures pose serious stresses for the animal body, placing it in great danger of injury or even death. For animals, adaptation to varying climatic conditions includes both physiological mechanisms as a byproduct of evolution,
and the conscious development of cultural adaptations (Harrison et al., 1988; Weiss and Mann, 1985). There are four avenues of heat loss: convection, conduction, radiation, and evaporation (Wikipedia, 2012). If skin temperature is greater than that of the surroundings, the body can lose heat by radiation and conduction. But if
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