Perspective: Connecting the dots between domestic livestock ownership and child linear growth in low- and middle-income countries

Child stunting due to linear growth faltering remains a pervasive issue in low- and middle-income countries. Two schools of thought have existed pertaining to the role of domestic livestock ownership (DLO) in child linear growth. On one hand, it is argued that DLO leads to greater income and financial security, resulting in better child-raising conditions, including greater animal-source food (ASF) consumption, having protective effects towards child stunting. On the other hand, researchers argue that DLO contributes to faecal contamination and transmission of zoonotic enteric infections from animals to children, thus having destructive effects on child growth. Reviews of this association have revealed ambiguous findings. In this perspective, we argue that measuring the association between exposures to domesticated animals and child stunting is difficult and the ambiguous associations revealed are a result of confounding and differences in the management of DLO. We also argue that the increasingly prominent area of research of environmental enteric dysfunction, a sub-clinical condition of the small intestine thought to be due to frequent faecal pathogen exposure and associated with stunting, will be a useful tool to measure the potential destructive effects of DLO on child growth. We present our argument and identify challenges and considerations and directions for future research. Domestic livestock ownership in low- and middle-income countries can have positive or negative consequences for child linear growth. Safely managed animals that provide additional income and animal protein for households will improve child nutrition, but poorly managed animal faeces contribute to poor growth through repeated enteric infections. image Research shows mixed effects of domestic livestock ownership on child linear growth in low- and middle-income countries. Positive effects may flow on to improving child nutrition where animals and poultry are used for consumption or contribute to higher income and subsequent better child nutrition and home environment. Negative effects towards child growth occur where livestock is owned in such a way that infants are chronically exposed to animal faeces, which may result in environmental enteric dysfunction and diarrhoea. Stunting interventions must reduce infants' exposure to animal faeces whilst being sensitive to the role of livestock for the household economy.