Essential oils have been used for their medicinal and flavouring properties for hundreds of years, but a new market is emerging within the livestock sector in pursuit of a replacement for prophylactic antibiotic therapy. Hannah Noble reports.
Looking back 10 years, about 5 per cent of the poultry sector in the USA was using essential oils in their diets, says David Wilde, global innovation manager for Anpario, whereas now, he says, it is more like 50 per cent and growing.
He says: “The use of essential oils in livestock feed is an emerging market, but the potential is huge, especially in countries such as China, where antibiotic growth promoters are being removed. Producers are looking to other options and one alternative is essential oils.”
Mr Wilde says there are several types of essential oil. These include oils from dried herbs, steam distilled oils and those based on synthetic compounds.
His company focuses on marketing just one essential oil product, oregano. The company’s supply of oregano is grown in Eastern Europe, which provides the optimum climate for growing the herb, with hot summers for growth and essential frosts which stimulate the production of oil in the plant, which is a defence against insect attacks.
Mr Wilde says: “The oregano is grown to organic principles and is steam distilled.”
It takes two to three years for the plant to become mature enough to produce quality oil and the fields are usually down to oregano for 10-12 years.
Mr Wilde says published literature on essential oils shows there are antimicrobial and anti-inflammatory effects, along with some anti-oxidant and anti-parasitic effects.
He says: “The oregano is helping to support the animal’s own natural defences, supporting the gut and maintaining its health. If the animal has a more normal bacterial population, the gut will have more mucus and can absorb more nutrients. There will be better growth rates and the animal will be healthier.”
Research carried out by the AgriFood and Biosciences Institute, Northern Ireland, concluded calves fed the essential oil from birth were 2kg heavier at weaning at 56 days old and 2.9kg heavier at 70 days old. They also had a 6.8 per cent greater average daily gain than calves in the control group.
Mr Wilde says: “Also a study in conjunction with the University of Reading looking at antimicrobial resistance in calves being fed waste milk from the dairy herd saw a significant reduction in bacteria which had antimicrobial resistance in calves in the treatment group. These are really exciting and unexpected findings.”
Poultry research by North Carolina State University showed when chicks were given oregano oil from one day old, there was 17.4 per cent less variability in flock uniformity of body weight.
The shank length and rear quarter percentage were greater in the supplemented pullets compared with the control group, which they concluded may potentially improve pullet calcium storage capacity and readiness for shell production during onset of laying.
Trials have also been carried out on pigs in conjunction with Nottingham Trent University, where both sows and piglets were supplemented with oregano oil. The findings showed the supplemented sows maintained a higher body condition score at weaning with similar feed intakes when compared to those in the control group.
Piglets which received the treatment had a significantly higher daily average weight gain at one week old, which was combined with decreased morbidity. This resulted in a reduction of therapeutic treatment and reduced medication use.
Pre-weaning mortality also reduced from 14.3 per cent in the control group to 10.9 per cent in the treatment group.
Essential oils are first and foremost feed additives, says Mr Wilde, as they are classed as flavouring compounds, which he says is also an important benefit.
He says: “The taste and smell of the product helps to support and maintain the animal’s feed intake and that is especially important when transitioning at weaning and through different life stages. The consistent flavour can help to maintain intakes and reduce growth checks.
“Oregano oil is not a drug. We are not trying to cure a disease. We are not treating an animal.
“It is something we want to see included in the diet from about two days old to help support gut health and let the animal develop to the best of its genetic potential and, with the flavouring, help overcome any changes in diet and management.”