Adaptive Means of Coping with the Environment in Animal Production
Temporary acclimatisation has to do with adaptation to or tolerance to, a short duration of heat stress rather than to more moderate continuous heat stress. Temporary acclimatisation effect of the heat stress. The wide changes in heat stress between the day and night in three dry zones and between seasons of the year readily prepare animal to acclimatise and adapt easily.
Permanent acclimatisation to climate stress may be due to changes in the behavior of the animal or to changes in physiological relations that may or may not be inherited. Natural or artificial selection for morphological characteristics that assist the animal to acclimatised may be needed for permanent acclimatisation such changes in behavior of domestic livestock ought to form good management aims and indicators to facilitate the adaptation.
Common adaptive behaviours to heat stress by tropical livestock include sluggish movement to reduce muscular heat production, raising of the wings among poultry to allow for air circulation and heat loss; tendency of livestock to graze at night and more often seek to stay under shade in the hot day; drinking of large volume of water; slow rate and reduced consumption of feed; pigs.
Walloons in water ponds or moist environment and often stretch themselves in lying position. Physiological adaptations to tropical environment on the other hand are several and, often, not easily observed. These include:
• Decreasing the body metabolic rate and varying the body temperature
• Varying coater turnover (loss) by concentration of waste products in urine to conserve body water
Read Also: Basic Concepts of Adaptation and Acclimatisation in Animal Production
• Recycling of urea in the saliva to conserve nitrogen in period when forage is lacking
• Varying tolerance to salt concentration in drinking water
• Decreasing certain hormonal activity, for example, the thyroid and adrenal hormones
• Panting or reduction of body heat through the short and quick breath.
There are also morphological adaptations or characteristics that help to achieve environmental acclimatisation especially to temperate animal to tropical condition. These include:
• Possession of large skin area in relation to live weight especially develop or large comb
• Skin pigmentation, with short and light coloured hair to reduce heat and light radiation absorption
• Tendency to have thin layer of subcutaneous fat deposit
• Possession of long leg by Desert sheep or goats to cover long distance in search of feed and water.
Most adaptative features are derived from natural selection and they often form the basis for ultimate development of a new and more adapted breed or strain with minor manipulation by man, as the manager.
Breeding of animal for higher productivity must recognise important adaptive traits that may help to achieve good performance. Similarly, importation of livestock from a distinct environment to another need to take into consideration adaptation to major climatic factors and disease and parasite criteria, feed situation, prices of inputs and products as well.
Read Also: Effect of Tropical Climate on Animal Parasites, Vectors and Diseases