Biofuel co-products as livestock feed - Opportunities and challenges

Utilization of co-products of the biofuel industry as livestock feeds – a synthesis 517In Brazil, the Rural Social Biorefineries (RUSBI) approachhas been developed for small-scale farmers, especiallyin remote and marginal areas, to promote agriculturaldevelopment, food safety and energy self-sufficiency, ascooperatives rather than as associations in order to benefitmost from the prevailing tax system (Patino et al., 15).Similar developments in Colombia were adopted wherepetrol prices were high (Patino et al., 15).Braid (25) suggests that the biofuels industry is beingdriven by needs such as fuel security and governmentdemand for a pricing mechanism for carbon. Wiesman,Segman and Yarmolinsky (18) comment on incentives tothe biofuels industry, but also raise the question of penaltiesfor non-inclusion of biofuels in transport fuel withingovernment timeframes.The approach to small-scale farmers has also beenused in India with sweet sorghum being a major feedstockin a ‘decentralized’ system designed to encourage ruraldevelopment (Rao et al., 12). This allows small groups offarmers to develop local installations to produce syrup andsweet sorghum co-products and to send the syrup to acentralized unit for ethanol extraction (Rao et al., 12), thusavoiding the high cost of transporting the whole crop tothe centralized unit, and allowing local retention of theco-products. The viability of this approach depends on thesale of fodder bagasse, and producers are rapidly becomingaware of enhancing the value of this through chopping andsupplementation (Rao et al., 12).Erickson, Klopfenstein and Watson (5) point to theincreased N and P content of properly handled manure andthe GHG benefits to the rating of ethanol compared withgasoline if DGS is produced, the amount of P often beingsufficient to adopt a four-year rotation for this element. Thesavings in GHG largely accrue through the greater averagedaily gain (ADG) of feedlot cattle fed DGS, reducing thenumber of days in the feedlot, and, where transport distancesallow, the feeding of wet DGS saves emissions associatedwith drying the DG (Erickson, Klopfenstein and Watson, 5).Ravishanker et al. (24) argue that all photosyntheticprocesses should be subjected to a full audit at all stages ofenergy production, an approach currently missing. In Brazil,increased availability of potentially cheap energy sourcesfor livestock, as a result of the expansion of biodieselproduction, has created opportunities for rural farmersto intensify domestification of a wild game species, thecollared peccary (de Albuquerque et al., 14).KNOWLEDGE GAPS AND FUTURE RESEARCHNEEDSThe biofuels industry has evolved rapidly over the last two orthree decades with developments in processing techniquesand an expansion of the range of plants and other naturalenergy sources being considered as feedstocks. On-farmapplication of the co-products, on which the viability ofthe industry depends, is often ahead of unbiased researchto support its use, and there is a growing demand forstandardization of products. This has generated a needfor research to fill in the gaps of knowledge from existingprogress, to seek answers to problems that are known toexist, and to be ready to answer questions raised by futuredevelopments. This is against the backdrop of an industrythat started as an outlet for grain-based residues fromthe production of alcoholic beverages, which were fed topigs and cattle, to one that has grown to importance inprotecting the environment and safeguarding dwindlingsupplies of fossil fuels.Tables 4 to 6 summarize the research seen as necessaryat the present time, which includes assessing current andpotential feedstocks, and the nutritional needs of mostspecies of livestock, poultry, and aquaculture. Much of thepotential research identified as needed is concerned withco-product feeding value, the need for standardizationof products from within an individual plant and betweenplants, and the search for new feedstocks, particularlythose indigenous to an area but underutilized, togetherwith safety standards (including detoxification of seedmeals where necessary). Coupled with this is the need toconsider the species to which the co-product is to be fed.The knowledge gaps identified in Chapters 1 to 27inevitably show a degree of overlap, such that in somecases the positioning of a topic within the four tables mayappear arbitrary. Table 4 concentrates on DG, includingsome of the potential constraints in its use. Table 5 bringstogether suggestions for investigating co-products fromfeedstocks other than cereals, including the programmeon micro-algae. Table 6 lists areas for nutritional researchrelating to a specific livestock species, although it isaccepted that the work involving jatropha co-products andcamelina meal would have been equally at home in Table 5.Table 6 presents the areas that belong in neither Table 4nor 5, but all of which have relevance if the co-productsindustry is to remain economically viable and to benefit allsectors of the livestock industry.A major impetus to progress is the need to meetinternational targets to use biofuels for road transport andto reduce GHG emissions within an agreed timeframe.The success of the industry will depend in part ongovernments creating the enabling conditions for meetingthe targets, and Lywood and Pinkney (2) suggest that thiswill be easier in Europe for bio-ethanol than for biodiesel.In Australia, sustainability will depend on re-examination ofthe criteria and indicators of standards for biofuels (Braid,25). Establishment of a DDGS industry in Western Canadawill have to be done against the backdrop of cheap importsfrom the USA and is unlikely to succeed unless public andprivate bodies work together (Christensen et al., 26).