Anthropogenic climate change is expected to have major impacts on domesticated livestock, including increased heat stress in animals in both intensive and extensive livestock systems. We estimate the changes in the number of extreme heat stress days per year for animals raised outdoors that can be expected in the major domesticated animal species (cattle, sheep, goats, poultry, and pigs) across the globe during this century. We used the temperature humidity index as a proxy for heat stress, calculated using temperature and relative humidity data collated from an ensemble of CMIP6 climate model output for mid and end century. We estimate changes in the proportions of different livestock species that may be at increased risk of extreme heat stress under two contrasting greenhouse gas emission scenarios. Results are discussed in relation to changes in the suitability of different climate conditions for domesticated livestock during the current century. We find that by end century, extreme heat stress risk is projected to increase for all livestock species in many parts of the tropics and some of the temperate zones, and to become climatically more widespread, compared to 2000. Although adaptation options exist for both intensive and extensive livestock production systems, the increasing pervasiveness of extreme heat stress risk in the future will seriously challenge the viability of outdoor livestock keeping, particularly in the lower latitudes in lower and middle‐income countries where the costs of adaptation may be challenging to address.

Livestock have long been integral to food production systems, often not by choice but by need. While our knowledge of livestock greenhouse gas (GHG) emissions mitigation has evolved, the prevailing focus has been—somewhat myopically—on technology applications associated with mitigation. Here, we (1) examine the global distribution of livestock GHG emissions, (2) explore social, economic and environmental co‐benefits and trade‐offs associated with mitigation interventions and (3) critique approaches for quantifying GHG emissions. This review uncovered many insights. First, while GHG emissions from ruminant livestock are greatest in low‐ and middle‐income countries (LMIC; globally, 66% of emissions are produced by Latin America and the Caribbean, East and southeast Asia and south Asia), the majority of mitigation strategies are designed for developed countries. This serious concern is heightened by the fact that 80% of growth in global meat production over the next decade will occur in LMIC. Second, few studies concurrently assess social, economic and environmental aspects of mitigation. Of the 54 interventions reviewed, only 16 had triple‐bottom line benefit with medium–high mitigation potential. Third, while efforts designed to stimulate the adoption of strategies allowing both emissions reduction (ER) and carbon sequestration (CS) would achieve the greatest net emissions mitigation, CS measures have greater potential mitigation and co‐benefits. The scientific community must shift attention away from the prevailing myopic lens on carbon, towards more holistic, systems‐based, multi‐metric approaches that carefully consider the raison d'être for livestock systems. Consequential life cycle assessments and systems‐aligned ‘socio‐economic planetary boundaries’ offer useful starting points that may uncover leverage points and cross‐scale emergent properties. The derivation of harmonized, globally reconciled sustainability metrics requires iterative dialogue between stakeholders at all levels. Greater emphasis on the simultaneous characterization of multiple sustainability dimensions would help avoid situations where progress made in one area causes maladaptive outcomes in other areas.

Livestock provides an important source of income and nourishment for around one billion rural households worldwide. Demand for livestock food products is increasing, especially in developing countries, and there are opportunities to increase production to meet local demand and increase farm incomes. Estimating the scale of livestock yield gaps and better understanding factors limiting current production will help to define the technological and investment needs in each livestock sector. The aim of this paper is to quantify livestock yield gaps and evaluate opportunities to increase dairy production in Sub-Saharan Africa and South Asia, using case studies from Ethiopia and India. We combined three different methods in our approach. Benchmarking and a frontier analysis were used to estimate attainable milk yields based on survey data. Household modelling was then used to simulate the effects of various interventions on dairy production and income. We tested interventions based on improved livestock nutrition and genetics in the extensive lowland grazing zone and highland mixed crop-livestock zones of Ethiopia, and the intensive irrigated and rainfed zones of India. Our analyses indicate that there are considerable yield gaps for dairy production in both countries, and opportunities to increase production using the interventions tested. In some cases, combined interventions could increase production past currently attainable livestock yields.

• Household modelling highlights ways to increase goat production. • Large increases in goat meat production are possible in Ethiopia and India. • Increasing goat production did not always increase household income. • Yield gaps are best addressed by integrated technologies using a systems approach.

Context: Increasing demand for livestock products in developing countries provides opportunities for smallholder farmers to increase and diversify their income through increased livestock production. However, livestock production in these systems is often limited by inadequate animal nutrition, and farmers need ways to increase the availability and quality of livestock feed without compromising yields of food crops or increasing the area of land planted to forages. Aim: Using eastern Indonesia as a case study, we explore the potential for herbaceous legumes, integrated into existing mixed crop–livestock systems, to address specific production issues in smallholder beef systems. Methods: Through a series of in-village feeding demonstrations, we tested three opportunities to increase livestock production through the use of herbaceous legumes: (i) increasing reproduction rates of cows by maintaining their liveweight (LW) and body condition score during the dry season; (ii) increasing the survival and LW gain of unweaned calves; and (iii) increasing LW gain of growing bulls. Key results: Small amounts of legume (~10 g DM/kg LW) were enough to maintain LW of cows grazing poor-quality grasses and crop residues during the dry season. At higher levels of inclusion in the diet (~20 g DM/kg LW), feeding legumes increased the LW gain of growing cattle and survival of unweaned calves, providing benefits similar to a purchased concentrate, but at lower cost. Conclusions: Our results demonstrate how strategic use of herbaceous legumes can increase beef production from low-input systems by maintaining LW of cows, and increasing survival of unweaned calves and LW gain of growing bulls. Implications: Integration of herbaceous legumes into existing cropping systems removes many of the barriers to supplementary feeding. Improved livestock nutrition does not need to be based on purchased concentrates or increases in land used for forage production. The results are applicable to many other mixed crop–livestock systems throughout Southeast Asia.