Can agriculture close the loop in animal feed?

Sensemaking / Can agriculture close the loop in animal feed?

One of the biggest challenges in providing food for a growing population is feeding the animals that feed us. Can we find the solution in agricultural by-products?

By Gillian Phair / 16 Jun 2015

Animal feed comprises the most expensive part of livestock agriculture. Soy, corn and grain are the most common types of animal feed, but their use triggers several economic, social and sustainability issues.

During the rise of agricultural production in the 20th century, both plant crops and animal matter, known as 'swill' were used as livestock feed. However, since the BSC outbreak in 1992 and foot-and-mouth epidemic in 2001, swill was discouraged and legislated against in many countries. Feeding swill to pigs is still illegal in Australia and Europe.

In the context of rising meat demand due to global economic and population growth, production of plant-based feed, especially soy and corn,  increased, creating a global surplus. This has caused the value of these commodities to fluctuate and drop since their peak in 2012, despite the rise in fuel, fertiliser and seed costs. 

Livestock feed products are subject to great price volatility. Despite food price inflation, consumer demand for low priced meat allows supermarkets to press farmers on product prices. The impact for farmers is devastating – around half of US corn and soy producers earn less than their production costs, and the remainder hardly break even. The flux in corn and soy prices can encourage farmers to plant more of the more economically viable crop, creating larger monocultures, and driving increased use of pesticides.

Furthermore, the land, water and energy resources used to produce plant based livestock feed is highly inefficient. It takes 12 pounds of grain, 2,500 gallons of water and 35 pounds of topsoil to produce one pound of beef.

Closing the loop in animal feed 

In response to these pressing issues, there has been an emerging market for agricultural feed produced using waste by-products of the agriculture and food processing industries. When producing a food crop or livestock product, there are inevitable losses of valuable proteins, which has persuaded many industries to employ ‘closed loop’ agriculture.

For example, single cell proteins and nutrient-rich feed can be produced from:

- Potato juice and pulp from the potato starch industry

- Carcass debris carried in the waste water produced on chicken farms

- Animal hair, when treated with calcium hydroxide

- Fish excrement, which can be used to fertilise fruit and vegetables.

- Seeds of cotton plants.

- Whey waste from cheese production. 

These methods create value in the waste stream of production processes. There are economic benefits of creating an inexpensive repurposed protein product which can compete with conventional protein feed sources, and increase worth of the original product. For example, cotton seeds can triple or quadruple the value of a single cotton plant. With projections of rising levied landfill tax in the UK and elsewhere, the reuse and redirection of waste stream can be a more viable option for food producers, which also minimises the impact of the waste stream on the environment. For example, whey waste has a high organic content which can cause aquatic life to become deprived of oxygen when disposed into the environment.

Counteracting the ‘cornucopia' 

Closed loop agriculture is a way in which we can confront our dependence on soy and corn and create food sovereignty in animal agriculture. The UK pig industry has reduced its reliance on soy by half in the last 10 years, through use of peas, beans and food and drinks production waste. In 2012, 2.2 million tonnes of UK animal agriculture waste were used to feed animals out of an estimated 7millin tonnes of food waste (including domestic and international production). Anaerobic digestion and composting is a competing outlet for organic waste, as 1.3 million tonnes of food manufacturing waste in 2012 was processed for fuel, energy and compost.

Mark Driscoll, Head of Food at Forum for the Future notes ‘There is a real opportunity to ensure that we re-use nutrients and proteins within the food and agricultural system – feeding food wastes from other processes either directly to humans or via livestock has to be a key priority over waste to energy systems, such as AD’

A huge variety of agricultural wastes can be viable as an agricultural feed product. However, many ‘closed loop’ alternatives can only be used as ingredients – not as a full food source. 

Is the growth of ‘closed loop agriculture’ also limited by fears of another livestock disease epidemic (such as BSE), and probable ban on swill feed products?

Given the investment of time and money required to create ‘closed loop’ feed options, will export of agricultural food wastes to a growing number of anaerobic digestion facilities become a more favourable option in in reducing agricultural waste streams? 

The main question is, can these repurposed waste products come to scale to effectively reduce the reliance on corn and soy products for animal feed, and meet global demands on meat products?

Trend briefing by Gillian Phair.

Image credit: United Soybean Board


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