If the US were to shift to entirely grass-finished beef (vs. grain-finished), then the US cattle population would have to increase by 30% relative to today, because grass-fed cattle gain weight more slowly than those fattened in feedlots. Furthermore, existing pastures would have to become 40%-370% more productive to avoid converting more natural habitat to farmland or competition with human food supply. Methane emissions from the cattle’s digestive systems might increase by 43%, again because of slower growth rates.

Writing in the Guardian, Isabella Tree of Knepp Castle Estate argues that vegan diets ignore the potential of wildlife-friendly livestock grazing methods. Tree claims that not using anti-worming agents or antibiotics allows cow dung to feed various soil organisms, contributing to soil restoration and wildlife diversity.

New Zealand’s Parliamentary Commissioner for the Environment has released a report exploring how much and over what timescale the climate is affected by methane emissions from livestock. It focused on two questions. First,if methane emissions from livestock were held at current levels or followed business-as-usual trajectories, what would their contribution to future warming be? Second, what reduction in methane emissions from livestock would be needed so that they cause no additional contribution to warming?

A new paper has estimated the economic and environmental potential of feeding livestock with industrially-fermented microbes such as bacteria, yeast, fungi and algae instead of crop-based feed. The study finds that microbial protein could replace 10-19% of crop-based animal feed protein, with decreases in land use, climate impact and nitrogen pollution.

This paper, by FCRN member Hannah van Zanten (and whose authors include FCRN director Tara Garnett), calculates that a food system where livestock are fed only on food waste and industrial and agricultural by-products could provide 9 to 23 g of animal protein to the daily human diet (compared to daily protein needs of 50 to 60 g per person) while using one quarter less land than a food system with no livestock. The paper notes that the waste-fed livestock system could allow people in Asia and Africa to increase their consumption of animal protein, but that current consumption levels in other areas are higher than would be possible under a waste-fed livestock system.

Sixty suppliers of meat and fish have been ranked according to their management of nine sustainability categories, in an index prepared by Farm Animal Investment Risk and Return (FAIRR), a London-based investor initiative focused on the environmental, social and ethical issues of factory farming. 60% of the companies assessed are deemed “high-risk” on their overall sustainability strategy (or lack of it). Antibiotics are the most poorly managed risk, while waste and pollution are the best-managed risks.

This book, by Henry Buller and Emma Roe, examines issues of animal welfare in the food supply chain. Topics include the care of farm animals, the ethics of using welfare as a marketing tool and the links between globalisation of farm animal welfare.

Eating Better has published a new report setting out their suggested approach to eating “less and better” meat and dairy. They set out eight principles, including: eat less meat and dairy; reduce waste; choose smaller scale, higher standard producers; and avoid livestock fed on imported feedstuffs such as soy. The report also includes a guide to assurance and labelling schemes to help people choose better meat and dairy.

This report from the UK NGO Sustainable Food Trust shows that one in three small abattoirs in the UK have closed in the last decade, which could mean that marketing locally-produced, traceable meat will not be possible in some areas.