Novel plants may have major benefits for livestock production and human health

29^th January 2002

Scientists at the Rowett Research Institute, Aberdeen, are heading an EU-backed research project to explore the potential of a range of novel plants and plant extracts which it is believed could increase the efficiency of livestock production, help the environment, and slow the spread of antibiotic resistance in human infections. The ‘novel plants’ research project, of which the Rowett is the co-ordinating body, involves academic and commercial partners in Switzerland, Ireland, Spain, Germany and the UK. The work is funded by the EU at 1.94m euros, plus a contribution of 137,640 euros from the Swiss government.

The Rowett’s Dr John Wallace, project leader, says that these plants, which are already growing naturally in many parts of the world, appear to offer a ‘safe, green alternative’ to existing animal feed additives, and, if developed for use throughout Europe, would create significant environmental and human health benefits. Dr Wallace, head of the Microbial Metabolism research group at the Rowett, also says that the new plants could offer farmers a highly effective alternative to man-made feed additives, including antibiotics, which producers in many countries are still using to improve animal productivity and welfare.

"We know that the release of methane from ruminants is extremely damaging to the environment," he said. "Currently, however, methane release levels are increasing at an exponential rate. We believe our work has the potential to halt this increase and help stabilise the environment by taking a natural route to improved rumen fermentation.

"At the same time, we believe that the current growth in antibiotic resistance in humans, part of which is generally accepted to be linked to the use of antibiotics in animal feeding, could also be reduced by quite a substantial amount.

"In each case, the gains in environmental and human welfare appear to be achievable in harmony with animal production requirements, and at the same time will even improve ruminant performance."

The Rowett’s interest in the potential feeding value of new plant species draws much of its inspiration from 20 years of working with the International Livestock Research Institute in Addis Ababa, Ethiopia.

"ILRI has a huge collection of plants which grow in tropical and subtropical regions," said Dr Wallace. "We’ve been involved in screening this collection as our part in ILRI’s search for crops which might be more drought and pest-resistant than those which are presently being grown in Africa for feeding to farm animals.

"A major concern, of course, in introducing any new crop as an animal feed is that it might be toxic to rumen microorganisms. In screening the toxicity of new plants for ILRI, in fact, we found some that were very toxic indeed.

"However, we also found some which appear to have significant potential value as rumen-manipulating agents with an associated capacity to lead to reduced methane output from the animals concerned. We’re now beginning to examine similar ‘promising plants’ more closely as part of the new EU-supported project.

"For example, foliage from a tree species which we’ve been working with in Africa appears to suppress the protozoa which inhabit the rumen. This suppression leads to a significant improvement in production efficiency, resulting in less methane. We obviously want to take this examination further and to explore its potential within a European production environment."

In addition to the work with ILRI, other research at the Rowett has recently shown that essential oils, mainly aromatic natural extracts of herbs such as thyme, mint and others, have a specific and beneficial effect on rumen bacteria.

"Here again, we believe that naturally-produced essential oils could be used safely to manipulate rumen fermentation to the immediate benefit of farm animal performance, and the longer term benefit of human health and the environment," said Dr Wallace.

He also made the point that, if natural plant sources could be shown to be effective in offering improved rumen control, producers would be able to switch from man-made feed additives to plants and plant extracts. Given that antibiotics are used in some cases to aid rumen performance, any move towards the use of natural products could only be of benefit in combating the current growth in antibiotic resistance.

"Ideally," he added, "we’re looking for plants and plant extracts which can be produced effectively on European farms, will be safe to feed to livestock, and will offer significant natural improvements in rumen fermentation. The use of such plants, according to what we already know, would yield a lasting decrease in methane release from ruminants while also having a beneficial impact on the fight to minimise the rise in antibiotic resistance in humans."

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For further information please contact Dr John Wallace on 01224 716656

or Sue Bird, PR Manager on 01224 716668, mobile 07711 093417

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