Effects of the climatic environment on animal production, biotic agents, nutrition including the influence on animal feed supply and animal feed store or quality may be regarded as indirect effect that does not bear on immediate conduct of the animal but on its environment. For example:
Climatic Environment Effect on Feed Supply
Climatic environment affects the quantity and quality of feed available to the animal. Temperature , Precipitation , Daylight and Humidity limit plant growth and affect feed quality more drastically than other climatic factors.
In humid and sub humid areas where there is sufficient rains, plant exhibit seasonal growth, hence seasonal available of forage. In the dry season when plant experience slow growth or complete growth seizure, available grazing stuff declines and animals lack enough to eat.
In the arid and semi- arid zone lack of sufficient grazing material results in seasonal movement search of forage feed in the wetter areas. The pattern of distribution of rainfall in which in tropical region experience torrential rainfall in a short duration also partly explain rapid growth of plants within a short while followed by fast decline in biomass energy and other nutritional qualities.
Nutritional quality of feed has to do with proportion of constituent nutrients, availability and balance of this nutrients in the ratio needed by the animals. Feed quality is most influenced by the climatic environment factors as precipitation and humidity.
Rapid growth of plants results production of high fibrous content of the forage feed as quality deteriorates with age. Tropical forage compared with that of temperate matures quicker, such that at same age the fibre content is higher; and digestible protein and total digestible nutrients lower.
Thus stocks in the tropics usually have to digest more fibrous feeds and this may add to their heat load. Studies have indicated the extreme sensitivity of cattle to heat stress.
It is noted that the balance of acetate available for purposes other than heat production is increased as environmental temperature increases. Ruminants in hot climate are more sensitive to imbalances of protein-energy, which results in an increased heat production.
High temperatures and high humidity provide favorable breeding environment for internal and external parasites, fungi and disease vectors. There is high incidence of internal parasites in the humid tropics and in the wet season.
In arid areas, and in dry season, the incidence of insect pests and external parasites remain a major health threat. As much as the vegetation-type influences the incidence of insect pests/vectors of disease, so much is climate indirectly affects animal production.
Incidence of tsetse fly infestation and interaction between the humid and sub humid area explains the interaction between the climate and vegetation and their influence on an animal production.
Heat/ humidity stress may have all or some of the following effects:
- Increases the requirement for protein by the animal
- Decreases the efficiency with which metabolisable energy is utilized
- Heat stressed animals must reduce feed intake
- An unbalanced diet which leads to excessive metabolic heat production will compound the effects of heat stress due to climatic condition.
Tropical climate favors the rapid deterioration and increases the cost of handling animal products. In arid or humid climates of the tropics, substantial quantity of animal products have been lost to putrefying organisms which multiply rapidly under such conditions to cause deterioration, spoilage and ‘food poisoning’ of enormous economic value.
This indirectly affects animal production in terms of high cost of reduce wastage of valuable animal products.