Erb et al., 2012

https://www.gastronomiaycia.com/wp-content/uploads/2012/10/informe_producion_ganadera_seguridad-alimentaria.pdf
Brief here: https://www.ciwf.org.uk/media/3758836/Food-security-and-farm-animal-welfare-report.pdf

Erb, K. H., Mayer, A., Kastner, T., Sallet, K. E., & Haberl, H. (2012). The impact of industrial grain fed livestock production on food security: an extended literature review. Commissioned by compassion in world farming. The Tubney Charitable Trust and World Society for the Protection of Animals, London, UK.

read up to page 9 and read conclusions

They note that prior to their study few studies existed.

Negative effects of increasing intensification (that often goes along with market orientation), include the reduced ability of smallholders to participate in market, in particular related to production practices that show large effects of economies of scale (e.g. poultry production). Barriers to market participation for smallholders include high transaction costs, investment risks, and food safety regulations, in particular relevant for poor smallholders. Subsidies have a similar effect, as large producers often have a better access to subsidy systems.

The on-going structural changes in livestock systems put particular pressure on pastoralist societies, which currently consist of approximately 20 million households Is pastoralism the solution to the problems food security and animal agriculture.

Another disadvantage of intensified, in particular land-less livestock systems is the breaking up of nutrient cycles, which results in areas of nutrient depletion and areas of nutrient concentration and subsequent problems of e.g. water contamination. Mixed systems, in contrast, have the advantage to be potentially able to hold nutrients in smaller cycles, as manure (a valuable fertilizer) will be available at the farm and so reduce the demand for mineral fertilizers. See Manure from animal agriculture

They find that the extra land required to give farm animals roaming space is negligable compared to the extra land needed to grow their feed. This means that calls for intensified farming where animals are confined to tight spaces are misguided.

in SS Africa grazing land is not limited, however in Asia there is good crop land but not enough grazing land.

In this study, we identify 10 mechanisms or “hot spots” of the interrelation between livestock
systems and food security: