Why essential oils can reduce stress in chickens

Anyone can suffer from stress when they are taken out of their comfort zone, and this is no different for poultry.

Changes in the exterior and/or interior temperature, inadequate ventilation, rain, relocation, placement of “play objects”, unusual noises, unexpected visitors – all can disrupt the “normal” environment and so bring on stress.

A critical time in laying poultry is at transfer – with birds not knowing where food and water are located.

Mixing of groups and competition between birds will increase tension. When birds first go out to range can be a challenging time too.

See also: Split-feeding proves perfect formula for eggs

Stress will be exhibited at many levels: in production through deformed egg shells; in body condition through feather loss; and in behaviour through pecking.

Boredom and lack of space are two common factors which can quickly escalate to pecking at the neck and vent, leading to infection and ultimately, death.

Birds that are stressed will first have a reduced feed intake and display a disturbed balance of gut flora, known as dysbiosis.

Toxins are produced and the birds flush these out through droppings with high moisture content, leading to dirtier eggs and an increase in eggs being downgraded.

Natural products

“While it is important to manage and reduce the stress factors that you have under your control, there are a number of natural products on the market which can be used to redress the balance of gut flora to maintain performance and production,” says Doug Steele, Harbro poultry specialist.

Doug Steele

Doug Steele

“Essential oils are known to have antibacterial, antioxidant, antiviral and antiprotozoan properties which can have an impact on coccidiosis. These effects will help promote a healthy gut and aid food digestion.”

Unlike predominantly pure oregano products, the combining of spices with essential oils gives rise to improved salivation and endogenous enzyme production, both improving gut well-being and digestion, he says.

Probiotics have also been used successfully, particularly lactobacillus farciminis.

Promoting “good” bacteria works in two ways, by actively producing lactic acid and by competitively excluding potentially pathogenic gut bacteria.

Both essential oils and probiotics can be used all the time, as an insurance policy, or during spikes in environmental disturbance or changes in growth and poorer feed efficiency.

Free-range challenge

While stress upsets the equilibrium of good and bad bacteria, free-range birds are constantly ingesting bacteria from their outdoor environment and, in this situation, altering the pH in the upper part of the digestive tract can have a beneficial effect.

Adding an organic acid to the water supply through a suitably acid-tolerant dosing pump lowers the pH to 3.8-4.0 and helps create a barrier to gut pathogen ingress.

Reduction in pH in the upper part of the digestive system also helps to ensure optimal commencement of protein digestion, so important with the expense of dietary protein compared with home-grown cereals.

The coating of slippery algae, known as bioflim, lining the water pipes back from the nipple drinkers provides a growth foothold for bacteria and yeasts, and some products also have the added benefit of removing that biofilm from the inside of pipes, ensuring clean water supply for beneficial rehydration.

The effect of using an organic acid combination along with an essential oil product can have a much better, synergistic effect, as cell wall puncturing leaves the door open for intracellular acid action. 

In the field

Craig Grant with his chickens

Craig Grant ©Jim Varney

Craig Grant has been using a blend of essential oils for more than a year as part of the split-feeding regime he uses to feed his 16,000 free-range and 32,000 colony birds at Little Skillymarno, Strichen in Aberdeenshire.

“We had an issue with birds exhibiting more aggressive behaviour in the mornings, such as fighting and pecking. They were going about with their heads up and chests out, just not settled,” he says.

“It has been 12 months since we started using the essential oils and, as soon as it was added to the diet, we could see that it calmed the birds down.”

Organic acid has also been added to the water since March, recording a drop in water pH from 6.8 to 4.2.

“Using a combination of management to identify and minimise stress, and nutritional strategies to optimise bird digestion will help keep both you and your flock in the comfort zone.”

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