Phytogenics are additives inspired by nature for animal feed intake, performance, product quality, and environmental friendliness. Among these additives, essential oils (EO) offer vast potential in animal feed for improving feed intake, feed efficiency, supporting health status, heat stress management, and product quality.
Phytogenic Ruminant Tech Lead
Cargill Animal Nutrition
In the past, the primary focus was on improving intake, performance, and feed efficiency in livestock for margin improvement on farms. This remains crucial for livestock viability and feeding the increasing population. Now, it’s equally important to enhance product quality (meat, eggs, milk) to meet consumer demand for food quality (nutrient levels) and food safety (no residues in products, no adverse health effects). Additionally, animal welfare and environmental impact have become key drivers due to societal pressure.
Balancing these three objectives (feed efficiency, product quality, and environmental impact) is challenging. However, using plant-based feed ingredients that are inspired by nature is one of the potential tools that may offer a way to achieve this compromise.
WHAT ARE PHYTOGENICS AND ESSENTIAL OILS?
The term “phytogenic feed additives” (PFA) was introduced by Delacon 30 years ago. Today, it represents an established and technical term in scientific literature, referring to plant-derived, bioactive substances.
Among these, essential oils (EO) are notable for their wide range of applications, including traditional medicine, cosmetics, perfumes, and more.
Essential oils are volatile, fragrant compounds extracted from plants. They are oily (though not fats), lipophilic, water-repellent, highly volatile, and odorous. The color of EO varies based on the plant source, which can be, among other, leaves (rosemary), branches (tea tree), stems (lemongrass), bark (cinnamon), roots (vetiver), rhizomes (ginger), bulbs (garlic), fruits (orange), seeds (anise), flowers (jasmine), or plant tops (thyme).
Essential oils are characterized by their plant origin (e.g., essential oil of Thymus vulgaris), the plant part used, and specific active compounds.
CHEMICAL COMPOSITION OF ESSENTIAL OILS
EOs are composed of aromatic molecules with specific chemical structures. They are synthesized from different pathways:
• Terpenoids: Molecules with isoprene units, synthesized from the acetyl-CoA pathway. Examples include limonene, pinene, menthol, and geraniol.
• Phenylpropanoids: Molecules with benzene rings, synthesized from phenylalanine. Examples include thymol, carvacrol, eugenol, and cinnamaldehyde.
Secondary metabolites are produced by plants for protection against pests, pathogens, and environmental stressors, to inhibit the growth of competitive plants, or to attract pollinators and seed dispersers. Secondary metabolites are present in the oils obtained by extraction from plants. The concentration of these metabolites in EOs varies based on growth conditions, development stage, and weather.
EXTRACTION, ENCAPSULATION, AND ANALYSIS OF ESSENTIAL OILS
EOs are mainly produced by distillation. The methods include:
• Water Distillation: Plants are mixed with water and heated directly.
• Steam Distillation: Plants are heated with steam.
• Water-Steam Distillation: Plants are mixed with water and heated by steam.
For citrus plants, essential oils are extracted from the peel via expression, a specific physical process. Other methods, like supercritical carbon dioxide extraction, are efficient but not recognized as essential oils in Europe.
TYPES OF ESSENTIAL OILS
• All-natural oils: Made from the origin plant or its parts, maintaining the natural ratio of ingredients.
• 100% natural oils: Mixtures of different all-natural oils without synthetic additives.
• Synthetic oil: Single-type EO produced chemically.
• Nature-identical EO: Blends of synthetic oils that mimic the natural chemical makeup.
• Combination oils: Mixture of natural and nature-identical oils.
Fractionated essential oils separate individual active compounds, and synthetic EOs are used to reduce production costs and environmental pressure.
RESEARCH IN ESSENTIAL OILS FOR THE FUTURE ANIMAL PRODUCTION
EOs are known for their palatability enhancing properties. However, research has shown that Eos may exert antimicrobial effects, anti-inflammatory purposes, and more. Encapsulation protects EOs from temperature, humidity, and pressure, improving handling, safety, and efficacy. Technologies like spray drying and fluidized bed coating reduce activity losses of the active compounds, improve shelf life, and enhance efficacy, bypassing the rumen for specific applications.
DELACON’S RESEARCH AND DEVELOPMENT PROCESS
Delacon tests EOs in ruminants to evaluate their potential in various situations. For that we have followed this research and development process in the figure 3.
The research process includes literature reviews and specific methodologies (in vitro, ex vivo, in silico) to test individual active substances and their synergies before animal trials.
EOs target different aspects of animal production:
• Nutrient metabolism: To improve the feed efficiency and to reduce losses: EOs with antimicrobial impacts (phenolic, aldehydic, and ketonic EOs) have moderate effects on the rumen protozoa, amylolytic, proteolytic, or fibrolytic microflora to slow nutrient degradation and reduce nutrient losses. Some of these effects may positively impact the management of methane mitigation and ammonia losses.
• Animal health: Research has shown that EOs may have direct antimicrobial effects and indirect effects (quorum sensing interference or QSI), which may result in reducing pathogenicity by disturbing bacterial communication.
• Animal welfare: Research has shown that EOs also show promise for deworming and fly management in ruminants.
In conclusion, essential oils offer vast potential in animal feed for improving feed intake, feed efficiency, supporting health status, heat stress management, and product quality. Effective management from extraction, analysis, and encapsulation to utilization is crucial.
This article only provides scientific information and should not be construed as marketing claims or guidance. All technical statements are based on scientific literature; references are available upon request.
About Thierry Aubert
Thierry Aubert is the technical lead in ruminants Micronutrition & Health Solutions at Cargill Animal Nutrition. Aubert’s duties and responsibilities at Cargill include technical support for plant extract additives, management of the portfolio with the category lead, management of research projects or collaboration with the Cargill team, training for the sales team and technical local team, collaboration with marketing for the product presentation, and technical and sales support for the company’s customers and distributors. Aubert also manages the support for different channels: Cargill, Provimi, external distributors.
