Methane is one of the greenhouse gases. Greenhouse gases contribute to a condition known as global warming in which temperatures of different places around the world rise above normal values. Global warming has raised a lot of concerns among most environmentalists around the world because of the effects of global warming are not addressed at their early stages then the lives of plants and animals living in the world are at very high risk of ending (Beauchemin & McGinn, 2005). Global warming and its effects can only be controlled if the emission of greenhouse gases into the atmosphere is minimized as much as possible. Methane is a major contributor to greenhouse gases and thus its emission into the atmosphere has to be reduced as much as possible.
Livestock farming is an agricultural practice that contributes to the high production of methane. The production of methane gas can be controlled by controlling the ratio of feeds that are given to ruminant animals. This is because the amount of methane produced by ruminant animals is proportional to the ratio of nutrients that are available in the animal feeds (Ellis, Kebreab, Odongo, Beauchemin, McGinn & Nkrumah, 2009). It is highly believed that if methane emission to the atmosphere especially from byproducts of ruminant animals is reduced then global warming can effectively be dealt with.
Understanding the variability of methane production about diet that is fed to ruminant animals especially cattle is a very important factor in decreasing the emission of greenhouse gases into the atmosphere. If the emission of greenhouses into the atmosphere is reduced, the variability of temperatures around the world will be a thing of the past. It is on this basis that most countries such as Canada and Australia are now committed to reducing the emissions of greenhouses by about 6% of the amounts produced by the year 1990 (Beauchemin & McGinn, 2005).
Studies have shown that methane emissions take place in the rumen of ruminant animals during the fermentation of feeds which is aided by microorganisms in the rumen. It has also been established that the emissions of methane from the rumen of ruminant animals represent the loss of productive energy which should be used by the animals (McLean & Tobin, 1987). The level of methane in the meat of beef cattle kept under intensive feedlot systems is usually lower than the level of methane in the meat of cattle under extensive grazing systems. This implies that the amount of methane available in the rumen highly depends on the diet of an animal (McLean & Tobin, 1987). It is therefore important to appropriately quantify the number of feeds given to cattle in feedlots to minimize methane emissions.
Previous experimental results showed that the digestibility of dry matter content (DMC) during the background phase of heifers was less than during the finishing phase. If the production of methane in the rumen is aided by microbial fermentation, then the dry matter must also affect methane production (Ellis, Kebreab, Odongo, Beauchemin, McGinn & Nkrumah, 2009). This gave a good background for researchers who wanted to study methane production in finishing bulls.
It was because of methane emission concerns and the effects of global warming that an experiment was undertaken in the Tullimba research feedlot facility in Australia. The experiment was conducted using 84 weaned Angulus bulls with known weights and the weights were monitored as the experiment proceeded (Beauchemin & McGinn, 2005). The main aims of the experiment were to quantify for finishing bulls in a feedlot if having a high dry matter intake decreased methane production rate, and are low methane producers likely to have potential environmental benefits.
Reference List
Beauchemin, K. & McGinn, M. (2005). Methane emissions from feedlot cattle fed barley or corn diets. Lethbridge, Alberta: Career and Technical Education. Journal of Animal Science; 83, 3.
Ellis, J., Kebreab, E., Odongo, N., Beauchemin, K., McGinn, S. & Nkrumah, D. (2009). Modeling methane production from beef cattle using linear and nonlinear approaches. Lethbridge, Alberta: Career and Technical Education. Journal of Animal Science; 87, 4.
McLean, J. & Tobin, G. (1987). Animal and Human Calorimetry. Edited by K. A. Johnson and D. E. Johnson. New York: Cambridge University Press, pp.159.