The paper "High Temperatures on Dairy Cattle Production and Potentially on Milk Composition and Quality " is an excellent example of a term paper on science. 1.0 Introduction The increase in ambient temperature forces the animal’ s body to regulate its core body temperature by varying both physiological and metabolic functions. However, a number of behavioral, health, and performance difficulties are associated with such alterations. Dairy cattle are considered more susceptible to high ambient temperature compared to other ruminant animals due to their increased metabolic rate as well as inadequate water retention mechanisms within their kidneys and gastrointestinal tract.
On the other hand, lactating cattle are largely affected by thermal stress (Bernabucci et. al. 2010). Therefore, intensification of the thermal stress and its frequent occurrence can be considered the most common climatic change issue of global concern in dairy cattle associated with high atmospheric temperature. In the tropical regions, ambient temperature has been pointed out as one of the key climatic constraints affecting dairy productivity. Research indicates that because of the genetic trade-offs required to maintain or control excessive heat in order to boost the potentiality of quality milk production, it is a hard task to control the ambient temperature and humidity being the most common climatic and environmental constraints particularly in the tropical regions (Mellado, 1998). 1.1 Hot environments and their effects on the performance of dairy cows Hot environments affect the productivity or performance of dairy cows in many ways.
In order to achieve the high performance of such domestic animals, it is crucial for the farmer to modify the diet and environmental conditions particularly the thermal factors such as air temperature, humidity as well as radiation rate.
For example, 4-24oC is the required temperature range for the lactating Holstein cows. This clearly indicates that above that temperature, the negative effects of heat stress are experienced which in turn causes a reduction in milk yield in dairy cows above 27oC. Therefore, it can be concluded that a decrease in growth rate, fertility and milk yield in hot environments is mostly associated with an increase within the body temperature of dairy cows (Toda & Ieki, 1999). It is important to note that the body temperature of animals can be achieved only if there is a balance between heat production and loss.
However, the heat loss of an animal under the extreme temperatures is affected by humidity and thus leading to low performance of dairy cows in hot or humid summers. On the other hand, heat production is closely related to the level of feed intake, hence affecting the production level of cows (Jordan, 2003). In general, high production in cows can be achieved in high heat conditions, notwithstanding the pronounced effects of such hot environments. The excessive body temperature of dairy cows in hot environments can be controlled by taking three major steps; sprinkling the cows with water, improvising sheds in the cows’ shed to increase heat loss from the animals.
In addition, the environmental temperature can be reduced by changing the structure of the cowshed and ensuring the efficient intake of feed energy by controlling the increment of the cows from feeding (Shibata, 1996).
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