**5. Contribution of beef and dairy cattle to green house gas (GHG) emissions, climate change and global food security**

Climate change could be defined as the raising of temperatures, elevation of carbon dioxide levels and precipitation changes, which will all affect agriculture and food production [12] causing drought and increased temperature extremes in many food production areas world-wide [5]. This increasing global temperatures and extreme heat stress could cause a decline in global food production, food

### *Impact of Beef and Milk Sourced from Cattle Production on Global Food Security DOI: http://dx.doi.org/10.5772/intechopen.99322*

availability, stability in food supplies and minimized access to food and food utilization [12]. There could be declining yield in major food crops such as maize and soybeans especially in the developing countries. As a response to address the challenge of emerging global climate change, the December 2015 UN Conference on Climate Change was held in Paris, France. There was an agreement adopted by 195 countries to implement the first universal climate agreement to combat climate change (COP21 2015). This agreement was set to limit global warming to less than 2°C as compared to the pre-industrial levels in the 21st Century. To reach this goal, it was estimated that global green house gas (GHG) emissions needs to be reduced by 40–70% by 2050 and carbon neutrality needs to be reached by the end of this century (COP21 2015). This could lead to an improvement in the sustainability of global food production.

Beef and dairy cattle production contributes to climate change through the emission of GHGs, and climate change could affect human health and well-being to a great extent [6]. The impact on human health occurs through morbidity and mortality from extreme climate events. The indirect outcomes of climate change effect could also occur through economic disruption loss of labour productivity, changing availability of food, water and materials [29].

Despite the above mentioned negative effects, how else could the raising of beef and dairy cattle contribute positively to climate change and impact on global food security? One of the ways to achieve this was stated as shifting to raising fewer and more productive animals, particularly ruminants of more productive breeds [3]. This would require enhanced access to breeding, animal health and higher ruminant feed production such as grasses, legumes, concentrate feeds and other inputs to keep such less hardy animals alive and productive. This could also lead to the attainment of lowered environmental temperatures [30] for the livestock. Another approach suggested world-wide is the promotion of tree planting or aggressive agro-forestry programmes in different countries, particularly in the tropics. The planting of forage legume browse plants such as *Gliricidiasepium*, *Laecaenaleucocephala*, *Sesbaniagrandiflora*, *Afzeliaafricana* could help to ameliorate the effect of climate change and at the same time provide fodder leaves for ruminants. Also, environmental preservation laws and policies could be enforced, particularly in the tropical low income countries such as Sub-Saharan Africa and Asia. There should be the encouragement of the formation of more forest reserves and the establishment of biological gardens in different countries in the world in order to minimize the destruction and extinction of valuable tree species. Beef and dairy cattle production could also have positive impact on climate change and global food security through the feeding of feed by-products, feedstuffs, feed ingredients and feed additives that result in the production of less methane gas into the atmosphere. In recent times, some researcher workers [31] observed that the inclusion of yeast (*Saccharomyces cerevisiae*) fermented polished rice or cassava root meal in a livestock diet could produce a feed supplement which could be used as concentrate diet for dairy ruminants. This feed supplement was found to have the capacity to modify rumen fermentation, lower methane production, which also resulted to improvement in growth rate and feed conversion.
