Feed or Food? How Livestock Factor into the Land-Use Debate
By Pasture for Life Research Officer Charlotte Wheeler
In a biodiversity depleted world facing increasing inequality and catastrophic climate change – can we really justify unnecessary (and frequently destructive) forms of land use?
University of Oxford’s platform TABLE recently published an excellent primer on some of the data and nuances surrounding the feed-food debate. Feed-food competition refers to the value of using an area of land to produce livestock “feed”, as opposed to using it to produce human “food”. This could be considered part of the broader land-use debate, which centres on the opportunity cost of dedicating areas of land to one use (such as agriculture, or biofuels) when they could be put towards other purposes entirely, whether that be different forms of agriculture, house building, forestry, habitat restoration, or any of the myriad ways that humans utlilise the non-ice covered surface of the planet.
(Photo: PfL certified Ballyboley Dexters, County Down)
At one end of the spectrum, it could be argued that any feed-food competition is unacceptable, since that arable land could be used to either produce crops for human consumption, or for other uses such as natural habitat. The primary alternative most often advocated for in our biodiversity depleted world is for rewilding or other forms of nature restoration. This line of reasoning is also typically paired with a concomitant reduction in meat consumption. This is due to the assumption that eliminating grain-based feed from livestock diets without a reduction in meat consumption would lead to a massive expansion of agricultural land due to the greater land requirements of extensified livestock production. For example, if soya were to be removed from pig’s diets it would be impossible to maintain current production levels without further land-use change, because alternative sources of protein such as beans are a less efficient protein source than soya due to a range of factors including their anti-nutritive qualities.
Feed-Food competition could be eliminated in either a plant-based agricultural system (where there is no competition for resources with livestock because there are no livestock) or in a pasture-fed and/or circular food system, where livestock are reared on forage and/or by-products or waste products from other industries. Rutten et al., recognise that while from some perspectives the opportunity cost of using arable land for non-food uses in itself constitutes a “waste”, from a financial perspective these areas would still have value and so might not be viewed as waste. This latter view risks potentially contributing to the “valorisation” of food waste, making it an integral part of the food system, rather than attempting to minimise it; most studies accept that there are significantly greater emission and resources savings from avoiding waste in the first place, than there are benefits from utilising it as a resource. The “Food Hierarchy” of waste advocates for priority being given to avoiding waste in the first place, followed by utilising it for humans, then by livestock, composting, and finally, anaerobic digestion.
Source: https://food.ec.europa.eu/safety/food-waste/eu-actions-against-food-waste/food-waste-measurement_en
The extent to which livestock occupy land and resources depends on a range of factors, many of which are complexly related. In most studies extensively reared livestock are treated as one homogenous category, despite the range of management approaches and different environmental conditions encompassed by this type of system. Extensive systems are generally recognised as requiring more land than intensive ones, even when accounting for the arable land required for feed production. This modelling is typically based on the assumption that extensive systems are conventional set-stocked systems rather than adaptive multi-paddock grazing ones, which can dramatically increase the productivity of a given area of land compared to set-stocking, as well as performing well along several environmental metrics including increases in soil carbon. Many models also fail to take into account multifunctional land uses such as the integration of livestock into arable systems, or tree-planting in both arable and pastoral contexts, or even conservation grazing for biodiversity and ecosystem benefits. While the specialised nature of contemporary intensive agriculture may view land as only being able to deliver one product or benefit, whether food, or biodiversity, more historical or non-commercial systems frequently generate multiple.
The majority of cattle in the UK are grain-finished to some extent, whether with a dedicated livestock feed, or from waste products such as brewers grains or food items not suitable for retail, whether whole foods such as potatoes, or processed items such as broken biscuits or tortillas. Grain finishing tends to allow for shorter finishing ages compared to the average pasture-fed system, and can reduce the amount of land required to bring an animal to slaughter weight. However, recent research from Rothamstead suggests that cell-grazing systems can deliver 140% higher live-weight gains per hectare than set-stocking, as the practice facilitates “substantially higher pasture growth”, while also delivering environmental benefits. If we were to incorporate agroforestry into these systems, and if they were managed without anthelmintics (which cell grazing can facilitate) then the biodiversity benefits of such systems would increase further. Incorporating livestock into arable rotations can also deliver benefits in terms of soil health and fertility, alongside a reduction in disease and weed burden, with the potential to improve crop yields while also providing a secondary “crop” of meat or dairy products from the same land area.
More holistic measures of sustainability such as the Public Goods Tool or Global Farm Metric recognise and attempt to incorporate some of these additional benefits and trade-offs such as soil health, carbon storage and sequestration, animal welfare, food security, and social capital. While we are used to the idea that certain metrics are a zero-sum equation with others, the reality is more nuanced and down to individual management than simple membership of a category. For example, Dr Harriet Bartlett’s research into different pig management systems found that system type (such as organic, RSPCA assured, Red Tractor, free range etc) was not a reliable predictor of welfare and environmental outcomes, with the best performing farms being found across all categories, suggesting that trade-offs were not inevitable and more a result of individual management. We should be careful to advocate for outcomes based frameworks rather than simple regime change.
This also ties to the concept of feed efficiency as outlined in a previous blog post. Feed efficiency is typically measured by Feed Conversion Ratio (the maximum amount of animal product that can be produced for the minimum amount of feed); in these calculations, farmed salmon and intensive broiler chickens typically have the most desirable FCR, whereas pasture-fed ruminants score the poorest. Their Feed Conversion Ratio can be improved by feeding them a higher protein diet, whether that is a dedicated soya-based livestock feed, or grain-based byproducts from human food production, because a smaller amount of grain-based feeds is required to produce a kg of meat or milk than pasture alone. Alternatively, rather than comparing the pure kg input for kg output, you can analyse the amount of feed that is of human-edible quality required to produce a kg of product, or the amount of human-edible content in the livestock feed required to produce a certain amount of human-edible meat or milk.
According to these later frames of analysis, grass-fed ruminants are the most efficient converters of feed (or forage in this case) as there is little to no competition with humans for arable resources, whilst monogastrics such as pigs, chickens, or farmed salmon are typically reared almost exclusively on grain-based feeds. If grass-fed livestock were to be grazed as part of arable rotations to cycle fertility and reduce dependence on synthetic nitrogen fertilisers, or grazed to maintain biodiversity in the rare meadows, heath, and other biodiversity rich habitats that require specialist grazing to exist, then their land-use footprint could be viewed as a net positive, rather than an opportunity cost. So while the 50% of land area in the UK that is used to grow livestock feed may seem sensible if considering the greater greenhouse gas efficiency of intensive livestock production, it does not reflect a more circular livestock economy, nor does it account for the various other ecological (and social) trade-offs at play in our food system. While we have seen a lot of modelling regarding how much land could be “freed up” from grazing if livestock farming were eliminated, perhaps a more interesting question would be – what would the national herd size be if stocking rates were determined by what is required to replace a certain percentage of synthetic inputs in arable systems, and/or maintain beneficial habitats for biodiversity?
The way an area of land is ultimately used (or not) by humans is dictated by more than pure utility and modelling exercises, but by cultural values, historic use, geopolitics and trade, legislation, land prices, etc. Units of land are also rarely fungible, meaning that we shouldn’t rely too much on models that predict idealised land use scenarios across a region as though there are no ecological, geological, or population differences shaping their present use pattern. When we look at the opportunity costs of land-use, it is also relevant to consider what scale we are considering, whether it be a global context, or a domestic one; this has particular implications in terms of food production and patterns of consumption, especially if land is “freed up” for uses other than agriculture in one area, only to incentivise further land use change in another. For example, if the UK were to reduce our national herd size, what policy mechanisms could we use to ensure that we don’t simply outsource that livestock production to another country, or convert the arable or grazing land to other uses such as crops for biofuels?
A changing climate also brings new considerations to light;, many UK farmers suffered devastating arable losses with the high levels of rainfall this past winter, while tree crops and livestock enterprises were less affected – perhaps rather than falling into the modelling trap of simply shifting from one form of land use to another, we should be looking to diversify through the stacking of land uses as a way to increase economic, as well as environmental resilience?
