Assessing the impact of climate action mitigation strategies from livestock production: A review – Solution for greenhouse gases mitigation

The main sources of greenhouse gas (GHG) emissions are enteric fermentation from ruminants and manure management. An integrated strategy-combination approach incorporating nutrition and manure management is necessary to dramatically reduce GHGs and the carbon footprint of milk production. The aim of this review was to assess the effect of climate action mitigation strategies on the GHG production of ruminant animals. This review was based on the different references, which are textbooks, journals, proceedings, conferences, and abstracts accessed through Agricola, Agris, CAB Abstracts, Embase, MEDLINE, and the Web of Science. The research findings were done by using dairy cattle, sheep, and goat; the numbers of animals used in each experiment were given the majority of attention, and decisions were also made based on the method used to quantify methane (CH 4 ) and nitrous oxide. Enteric CH 4 per unit of milk was reduced by 6–8% when higher-starch corn silage was used in place of barley or alfalfa silage. Cows fed seaweed (1.77–2%, on dry matter [DM] basis) experienced a linear drop in enteric CH 4 emission from 383 to 400 g/d. Supplementation of vegetable fats (6%) and coconut oil (12 g/day) to ruminant diets can decrease CH 4 emissions by 21–40% and 50–61.2%, respectively. Similarly, the addition of 21.5 g nitrate/kg DM reduces CH 4 yield (17%) in sheep. Bovaer can reduce methane emissions (30%) for dairy cows. Feed processing and additives are alternative strategies to minimize GHG production in ruminants, but further studies on additives and their residual effect on livestock output is needed.