An assessment of GHG emissions from small ruminants in comparison with GHG emissions from large ruminants and monogastric livestock

Greenhouse gas (GHG) emissions are expected to cause global warming which results in extreme weather changes that could affect crop yields and productivity, food supplies and food prices. It is also expected that climate change will have an impact on animal metabolism and health, reproduction and productivity. On the other hand, the expected increased demand of animal origin products in the coming years will increase the reared animal numbers and consequently GHG emissions. This paper outlines the main GHGs emitted from livestock which are CO 2 , CH 4 and N 2 O, coming from respiration, enteric fermentation and manure management respectively, with CH 4 and N 2 O having the highest global warming potential. Ruminant livestock has the highest contribution to these GHG emissions with small ruminants share being 12.25% of the total GHG emissions from livestock's enteric and manure CH 4 , and manure N 2 O in CO 2 equivalent, producing 9.45 kg CO 2 equivalent per kg body weight with the respective values for cattle, pigs and poultry being 5.45, 3.97 and 3.25. Since the production systems significantly affect the GHG emissions, the grazing, livestock crop complex, and intensive ones account for 30.5%, 67.29% and 5.51% for total CH 4 emission (from enteric fermentation and manure management) and 24.32%, 68.11% and 7.57% for N 2 O respectively. Taking into account the positive and negative impacts of small ruminant livestock production systems to the environmental aspects in general, it is recommended that a number of potentially effective measures should be taken and the appropriate mitigation technologies should be applied in order to reduce effectively and essentially the GHG emissions to the atmosphere, with no adverse effects on intensification and increased productivity of small ruminants production systems.