Animal board invited review: Benefits of livestock and animal-source foods in developing countries

Livestock support the livelihoods of approximately 1.3 billion people across the world and contribute up to 80% of the gross domestic product of certain countries. In addition to roles as a vital source of food, fiber, manure, traction, status, and insurance, livestock are pivotal for women's empowerment, sociocultural norms and festivities, and a variety of ecosystem services. Livestock also contribute to circular bioeconomies by consuming only 14% of human-edible food, while repurposing poor-quality crop residues and agricultural byproducts into nutrient-dense animal-source foods (ASFs). Livestock contribute 11.5% of global greenhouse gas emissions, but over 100 climate-smart interventions have been developed to mitigate the problem. Most of these have focused on high-income countries where they have drastically reduced methane emissions intensity over several decades. However, methane emission intensity is still high in most low- and middle-income countries (LMICs), where few available, affordable, and accessible climate-smart technologies have been deployed and adopted. Supplying 13 and 26% of the calories and protein consumed by humans, respectively, ASFs are the best natural and bioavailable sources of multiple simultaneously supplied micronutrients that are critical for preventing nutritional stunting, which affects 149 million children under 5. This includes 1 in 3 children who are stunted in South and Southeast Asia and sub-Saharan Africa and are likely therefore to experience lifelong underachievement. These micronutrients are also critical for preventing wasting or acute malnutrition, which is highly correlated with infant mortality, as well as underweight and anemia, which affects 35.7-47.4% of people in sub-Saharan Africa and South Asia. Consequently, ASFs are vital for physical growth, health, neurocognitive development, and hence for educational achievement and economic productivity. By contributing to preventing sarcopenia and osteoporosis, they are also important in the diets of older adults. Yet, adequate consumption of ASF in LMIC is constrained by high prices, lack of awareness of their nutritional potential, inaccessibility, sociocultural norms, and taboos etc. This manuscript reviews the importance of livestock and animal-source foods in LMIC and highlights important areas for future research, education, funding, and policy interventions.