After years as a poultry practitioner, I have witnessed a gradual shift in the way intensive farming is understood. Concepts like welfare, biosecurity and environmental enrichment have moved from the scientific papers, to the day-to-day routine on every farm.

Some of these changes have been driven by consumer demand, by farm assurance scheme requirements and by legislation. However, some change has come from farmers own motivation and increased awareness.

I would like to think that we are on a journey away from the “desensitized” animal production system and leading to a place where improving the quality of life for stock in a meaningful way is as important as our attempts to improve performance.

To achieve this, we need to implement the welfare ideal portrayed by the concept of the Five Freedoms at a deeper level:


We can see how all of them interlink to each other in a basal way and the aim of this exercise is not prioritizing one over the others in any way. However, for the scope of this article, we are going to focus on what “Freedom to express normal behaviour” entails and how it relates to the idea of “enrichment” in a general way. This is potentially the more abstract and complex freedom on its contents but essential in the thought process of realizing how important the bird’s “perception” of its quality of life is and how this is linked to its ability to fulfil normal behaviour.

In successive articles, we will explain how the different species of production animals can benefit from it in their daily lives.

In part, this concept lends itself to assessment of the environment, and what is present within it, to allow the birds to express a range of positive behaviours. Where behaviours or opportunities might be seen as lacking, the environment may need to be “enriched”, to allow a greater behavioural repertoire, consistent with a better quality of life (and a move towards a “Good Life”).

Our starting point is always going to be the same for each one of them: understanding poultry species at their most basic level.

We might have domesticated, selected and bred a bird through the years to produce an individual that can cope with life in captivity, tolerate humans and is full of genetic capabilities that we are exploring for production benefits. However, we cannot move away from the reality that we are working with an animal with a brain motivated to follow a complex “hard-wired” pattern of behaviours expressed through a daily routine.

For example, by observing a jungle fowl (our chicken predecessor) in the wild over 24 hours, we will see the bird expressing certain behaviours and getting involved a series of activities. A domestic hen returned to “feral” conditions will display the majority of these behaviours too!

This reinforces the fact that there are behaviours that are “hardwired”; not taught or learned. Research has found that hens are highly motivated to perform certain activities to the extent of them being regarded as welfare needs. This means that depriving birds from the opportunity to perform these behaviours may have marked welfare consequences, such as frustration and abnormal behaviour patterns.

The way to organize and describe this group of expected behavioural traits in any given species is called an Ethogram. If we collate all that data into a pie chart it might resemble something like this:

Each slice of the pie represents the proportion of time an animal spends performing each behaviour. The bigger the slice, the more time a bird spends performing that activity and the more important that activity may be regarded to be.

How might the Ethogram relate to environmental enrichment?

If we critically compare the wild and farm environments we can see that farmed birds are certainly provided with food (which is nutritionally balanced but perhaps lacking in variety), water and shelter but, more often than not, they live in a relatively confined space with a large group of other similarly sexed or aged birds

Owing to group size, the opportunity for socially interacting socially in a constructive manner is probably reduced and their ability to establish a suitable hierarchy is definitely more challenging.

Suddenly, with all this information in our hands, some of the differences between the time “budgets” of wild and farmed animals become apparent.  Our birds have fulfilled their basic needs in a fraction of the time and may occupy the “spare” time with whatever resources are at their disposal. This might include the appearance of undesirable/abnormal behaviours that not only have an economic impact for the owner but a component of frustration for the bird that we should be able to address.

To help us understand the areas where management techniques can have an impact on the animal wellbeing, Bloom-Smith et al (1991) provided a categorization of the different enrichment types:

–              Social Enrichment: Such as frequent walks and human interaction (remembering birds will equally appreciate solitude when performing some activities such as laying)

–              Occupational enrichment: Such as adding ramps, bales, balls, hanging objects

–              Physical Enrichment: Such as changing the layout within the house

–              Sensory Enrichment: Such as music, smells, different bedding

–              Nutritional Enrichment: Such as alfalfa, oyster shell, meal worms

Nowadays, the construction of modern poultry houses encompasses not only the physical welfare needs of our birds but also provides some of the necessary enrichment to fulfil their “other” emotional/mental needs (i.e. complexity of a multi-tier frame in layer production, perching in broiler houses, pecking objects in turkey houses… etc). Additional enrichment methods will have a cost, and it is possible that some of our efforts to mimic the wild bird’s ethogram will have unanticipated negative effects (e.g. Dawn-dusk dimming may lead to smothers; feeding on the floor to encourage foraging may promote disease and/or unevenness).

However, given the persistent presence of undesirable behaviours among farmed animals, there is an intuitive consensus that perhaps more needs to be done.

We are gradually learning where it is worth putting our effort, time and resources to synchronize our productivity needs to their specific physiological and behavioural needs even more for maximum performance.

Outwardly, occupational enrichment appears easy and appealing.  Most people can relate to the enriching and pleasurable effects of “toys” from childhood but, it is important to bear in mind that this is not a simple exercise of adding up “furniture”.

The widespread usage of random objects in the house (such as CD’s or balls) as a pecking distraction adds up a risk of fear reaction to the novel object too. 

Just remember we are dealing with a prey species. Fear in nature will be linked to avoidance and ultimately to survival, but in farmed animals is linked to stress and this, ultimately, to imbalance, disease and poor performance.

It is possible for us to teach birds coping strategies though, by using targeted enrichment efforts early in life. This means involving all the stages of production when the model includes more than one; rearing-laying or brooding- grow out.

Birds will benefit from early socialization and exposure to novel stimuli. This will help them become more tolerant to changes in their environment later in life and the fear responses will be reduced.

Simplistically, utilisation of this kind of enrichment needs to be assessed as there is an element of futility if we fail to see what the animal requires.

If interacting with the “toy” is not rewarding or suitably constructed and does not obviously have a parallel in the ethogram, the birds often rapidly lose interest in the object.  At such a point, it is no longer enriching but is merely occupying space and should be removed or replaced.

Other common efforts seen include the social enrichment where free range birds are mixed in some areas with other species. Whilst it poses a risk of disease, it is worth mentioning however, that some producers have used other species – such as Alpacas – to improve ranging behaviour in hens.  This may be by reducing fear reaction in birds to the risk of predators. Owing to the large size of this Alpacas, foxes for example do not venture in the range.

There are also opportunities for sensory/nutritional enrichment, but this can be a slow process of trial and error to find what works for each species. Further progress may well require collaborative efforts between industry, academia and appropriately motivated investors to help drive the research and provide the evidence for different types of enrichment in a commercial setting.

We could even go further by saying that sometimes adding something new is not necessary, but reassessing what it is already in the house and optimizing its use could equally be successful in accommodating the birds’ requirement for a specific need (such as more appealing substrate within the nest boxes, different lighting, different means of administration for grit or oyster shell, different material for perches, etc)

It might be my point of view, but I think that there is a tangible positive impact from working with the bird and adopting a holistic approach into its well-being.

There could be a long debate into how much of what we do on farms is really perceived by the bird and what “happy” means to a bird; however, what cannot be disputed is that animals are sentient beings and that, the quicker we learn about enrichment and bird behaviour, the quicker other concepts as sustainability, efficiency and profitability will join the equation.

Carol Lopez DVM MRCVS – Poultry Health Services Sutton Bonington