The climate change crisis is inducing severe energy and food shortages in tropical regions. A potential solution is to build agroecological systems as an alternative to intensive and industrial agriculture. For that research should focus on the functions of animal and livestock farming systems. Positive and negative function effects should be assessed. This is particularly important in developing countries where most of tomorrow’s food and feed will have to be produced. What are the main issues for animal production in the tropics? The major challenges are how to redesign productivity and food security, economic efficiency and environmental preservation, and how to integrate economy and environment. A multidisciplinary approach is necessary to address such complex problems, where interactions among interdependent components of the system result in multicausality. The concept of livestock farming system, with its double consistency of social and biophysical dimensions, can help address complex problems. The concepts of livestock farming system and of agroecology can be easily combined to design sustainable animal production systems. Enhancing agroecological approaches that lead to both food security and biodiversity conservation must involve spreading concepts through practices, particularly to solve the problems of small farmers. As so, the purpose of the paper is to highlight many case studies. The animal and farming system ecoservices are described at the animal level with the case of the multifunctional tropical goat and also at the territory level with the case of agrosylvopastoralism focusing the role played by the animal. Finally, the socio-cultural functions of animals or systems in this region are described. The double dimension of livestock system concept allows the integration of the livestock keepers in the human and societal context to attain agroecological objectives which is recognised as a core objective to attain according through the agroecological perspective. Topical livestock farming systems can show their potential to reach sustainability and help family economy.