Biofuel co-products as livestock feed - Opportunities and challenges

22Biofuel co-products as livestock feed – Opportunities and challengesTABLE 2Animal feeds prices – United Kingdom average price, 2008–2010 inclusiveFeed Price in GBP per tonne SourceFeed wheat 110 Farmers WeeklySoybean meal 302 Farmers WeeklyRapeseed meal 182 Farmers WeeklyWheat DDGS 179 LMC Intl. Ltdaccurately targeting optimum dietary protein or amino-acidlevels. In the EU, feed wheat that is in excess of demand isexported and soybean meal imports are adjusted to meetthe EU demand for animal feed protein. Feed wheat cantherefore be regarded as the marginal animal energy feedand imported soybean meal as the marginal high-proteinfeed. Average prices of selected animal feed materialsare shown in Table 2.Using substitution ratios from Table 3, the averagevalue of the soybean meal and wheat displaced by wheatDDGS is GBP 221/t of DDGS. Compared with the DDGSprice of GBP 179/t this gives a good margin to covercosts for blending and feed supplements. The DDGS andrapeseed meal prices will vary with soybean meal andwheat prices to ensure all co-product is utilized in animalfeed. Co-products, such as DDGS and rapeseed meal,from EU biofuel production will therefore displace a mixtureof soybean meal imported from South America andEU feed wheat in the animal feed formulation.The substitution ratios of biofuel co-products forcereals and soybean meal can be determined accuratelyby animal feed formulation models and checkedby animal feed trials. Most formulation work has beendone to determine the addition of DDGS and rapeseedmeal for particular diets. These tend to show that DDGSdisplaces mainly a mixture of soybean meal and cerealin mono gastric diets (Lywood, Pinkney and Cockerill,2009a) and a mixture of soybean meal, cereal and othermid-protein components in ruminant diets (Weightmanet al., 2010). However, all the mid-protein animal feedscomponents (rapeseed meal, sunflower meal and maizegluten) are secondary co-products from the productionof vegetable oils or wet maize milling, and the importsof all these components to the EU are small (Figure 11).They will therefore continue to be produced and will beused elsewhere in animal feed formulations, for exampledisplacing a mixture of soybean meal and wheat in pigand poultry feeds. Therefore DDGS and rapeseed mealwill directly or indirectly replace cereals and importedsoybean meal. In order to determine whether the DDGSgoes directly into pigs and poultry, or whether the DDGSgoes into ruminants and displaces other mid-proteincrops in pigs and poultry, will require more advancedanimal feed modelling, which maintains the total usageof mid-protein animal feed co-products.The displacement of soybean meal and cereals by biofuelco-products has been explored in various studies andthe results for DDGS and rapeseed meal for weightedaverage livestock groups in the EU are shown in Table 3.It may be seen that there is reasonably good agreementbetween the figures from different studies. It hasbeen shown (Lywood, Pinkney and Cockerill, 2009a)that these results are reasonably consistent with a modelwhereby the co-products displace soybean meal and cerealto give the same metabolizable energy and digestibleprotein in animal feed. This approach provides substitutionratios for a range of biofuel co-products and is used todetermine net land use for this study. These substitutionratios for different biofuel co-products for feed wheat andsoybean meal are illustrated and compared in Figure 13. Inpractice, these ratios will vary depending on the quantityof biofuel co-product (Weightman et al., 2010), variationsin relative prices of soybean meal and wheat, relativeabundance of alternative animal feeds, and variations inquality of animal feeds from different sources.In all cases, the animal feed co-product will beblended with more feed wheat to give the desired animalfeed composition, as shown in Figure 14 for the cases ofsoybean meal plus wheat, and wheat DDGS plus wheat,blended to give a typical animal feed energy:proteinratio.TABLE 3Substitution ratios for biofuel co-products in the EUCo-productSubstitution (t/t co-product)For soybean mealFor cerealNotesSourceWheat DDGS 0.50 0.66 CE Delft, 2008Maize DDGS 0.45 0.69 CE Delft, 2008Rapeseed meal 0.66 0.26 CE Delft, 2008Wheat DDGS 0.59 0.39 Lywood, Pinkney and Cockerill, 2009aMaize DDGS 0.40 0.49 Lywood, Pinkney and Cockerill, 2009aRapeseed meal 0.61 0.15 Lywood, Pinkney and Cockerill, 2009aWheat DDGS 0.60 N.A. High usage scenario Weightman et al., 2010Wheat DDGS 0.60 0.68 Aglink-Cosimo model Blanco-Fonseca et al., 2010Notes: N.A. = not available.