**2.1 Livestock and crop production in Africa**

Livestock production contributes between 30 and 50% of agricultural gross domestic production, mainly from the production of beef cattle, dairy cattle, goats, sheep, and chickens [4]. Africa has about 250 million Tropical Livestock Unit (TLU) equivalents [3] that support 70% of the rural livelihoods and provide income to over 200 million people. Livestock production is increasing throughout Africa, due to rising human population, urbanisation, and demand for meat. Total human population in the world is expected to reach 8.6 billion by 2035 and 9.8 billion by 2050 [5]. In addition to provision of food security and income, livestock provide draught power, transport, and manure in mixed crop-livestock systems. Also, livestock is socially and culturally important for payment of dowry, celebrations, and gifts to family members, and as a means of savings [6].

The livestock sector is widely constrained by a lack of regulation, which leads to negative externalities such as land degradation, water pollution, loss of biodiversity and emission of greenhouse gases (GHGs). Greenhouse gasses are the major causes of climate change, and the consensus is that climate change and global warming are real due to increased GHG emissions into the atmosphere.
