Assessing the environmental and nutritional potential of using biodiesel by-products (arising from both food and non-food crops) as ruminant feed


Biodiesel is a renewable fuel for diesel engines that can be manufactured from vegetable oils or animal fats. Greenhouse gases are reduced 20-40% with cereal-based ethanol production, 70-90% if cellulosic feedstocks are used to produce ethanol and 40-60% if canola or soybeans are used to produce biodiesel. However, the costs to reduce greenhouse gases by the production and use of biofuels (especially cereal-based ethanol) are very high; much greater greenhouse gas reductions can be achieved by other methods at lower costs.
• In a joint future project between The University of Sydney, the Brazilian Agricultural Research Corporation - Dairy Research Centre (EMBRAPA - CNPGL in Juiz de Fora/MG, Brazil), Federal University of Sao Joao and Agriculture and Agri-Food Canada our aims are to determine the effect replacing feed sources in livestock diets with press oils seeds and glycerol by-products of biodiesel production on:
1. ruminal fermentation patterns; feed digestibility; ruminal microbial populations; and methanogenic activity of ruminal archaea;
2. animal performance trials; and
3. the environmental safety and project sustainability.


Dr Alex Chaves

Research Location

Sydney School of Veterinary Science

Program Type



Benefits of the Project
1. Environmental impact: The utilization of a by-product from biofuel production will reduce impacts of agriculture on the environment. As well, reduced methane production would have favourable effects on the air quality and may improve animal performance as it is well established that lipid supplementation reduces ruminal methane production.
2. Nutritional impact: This research will be an effective means to improve efficiency of energy use by dairy cattle. The use of press cake as well as glycerol from biodiesel production may reduce GHG production and contribute to better performance of dairy cattle as fat supplementation has been shown to decrease methane emission in cattle. If press cakes act similarly to fat supplementation, their inclusion in ruminant rations will improve efficiency of energy utilization and mitigate GHG impacts of livestock on the ecosystem.
3. Milk production and composition: It is likely that the use of press cakes will also have an impact on milk production and composition. The increased energy supply should translate into higher milk production. As well, it has also been shown that feeding oil seeds can increase the concentration of conjugated linoleic acid (CLA; a potent anti-carcinogenic) in milk.
4. Public perception: Using biodiesel in a conventional diesel engine substantially reduces emissions of carbon monoxide, sulfates, aromatic hydrocarbons, and particulate matter. Most importantly, biodiesel reduces air toxics and cancer-causing compounds. This research offers an excellent opportunity for the livestock industries to evaluate an alternative use of press cake for feeding ruminants in order to maximize its use. The use of oil press cakes in animal nutrition will improve the perception of the public towards the dairy industry by showing the positive environmental aspects. Additional public benefits include improved environmental protection, health benefits (from using biodiesel in engines and improved milk fatty acid profiles from feeding press cake), enhanced local economic development and Green House Gas (GHG) reductions.

Additional Information

- Opportunity to travel overseas (Brazil and Canada) and work with a multidisciplinary team.
- Opportunity available for Masters or PhD student.
- Scholarship is not included so students who already have funding/or are applying for an APA have a greater chance with this opportunity.
- Eligibility criteria: discussed on individual basis.

Organisations Conducting the Research
Faculty of Veterinary Science - The University of Sydney, Sydney, NSW - Australia
EMBRAPA - CNPGL (Dairy Research Centre) - Juiz de Fora, MG - Brazil
Federal University of Sao Joao, Sao Joao del Rei, MG, Brazil
Agriculture and Agri-Food Canada, Dairy and Swine Research and Development Centre, Sherbrooke (Lennoxville Sector), Quebec

Additional supervisors include:
Drs Heloisa Carneiro and Luiz Gustavo Ribeiro Pereira - EMBRAPA - CNPGL (Dairy Research Centre) - Juiz de Fora, MG, Brazil
Dr Rogerio Mauricio PhD, Federal University of Sao Joao, Sao Joao del Rei, MG, Brazil
Dr Chaouki Benchaar PhD, Research Scientist, Agriculture and Agri-Food Canada,
Sustainable Production Systems, Sherbrooke, Quebec, Canada.Dr Tim McAllister PhD, Senior Scientist, Agriculture and Agri-Food Canada, Lethbridge Research Centre.

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fuel efficiency, ruminant performance, animal nutrition, Industry by-products, Greenhouse gases (GHG)

Opportunity ID

The opportunity ID for this research opportunity is: 1128

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