Opportunities and implications of using the co-products from biofuel production as feeds for livestock (1)

Abstract

Targets for biofuel use have been established in many countries, including the UK. Currently the main feedstocks in the UK are wheat for bioethanol and oilseed rape (OSR) for biodiesel. The main co-products of biofuel production from these feedstocks are dried distillers grains and solubles (DDGS), rapeseed meal (RSM) and glycerol, all of which can be used as livestock feeds. If all the UK target for biofuels are produced from home-grown crops, this could result in the production of up to 1.3 million tonnes of rapeseed meal (RSM), 1.0 million tonnes of wheat distillers dried grains with solubles (DDGS) and 210 kt of glycerol per annum by 2010. This represents about one quarter of current compound feed production. However, these quantities are unlikely to become available for use in livestock rations within the short-medium term. Limiting factors include OSR crush capacity, the use of imported feedstocks for oil production, the development of methods of producing ethanol from biomass (rather than wheat) and demand for use of these co-products in power generation.

DDGS and RSM are already widely used as feed materials in livestock rations. Published research suggests that there is scope for using more, although variability between production plants in the composition of co-products - particularly for bioethanol - may be a constraint. Considerable research has been undertaken in N America on the use of DDGS in livestock rations, but because maize - rather than wheat - is the main feedstock for bioethanol production caution is needed in interpreting N American results. If significant supplies of RSM and DDGS become available in the UK, protein sources used in compound feed formulations may change, and this will be reflected in changes in the total protein and amino acid profiles of rations. As a result, there could be increases in the amounts of nitrogen and phosphorus excreted by livestock.

The increasing global demand for biofuels will result in increased demand for the raw feedstocks (wheat, maize, soyabean and OSR). This in turn will result in an increase in livestock feed prices. This effect has already been observed in the UK, and the trend is likely to continue. In the longer term, the development of systems of bioethanol production from biomass, rather than food crops, is likely to have a major impact on both crop and livestock producers in the UK.