By the late 1960s in Europe and North America, poultry production had developed from a small-scale rural enterprise to an economically important branch of agriculture, explained Dr Ernst Fröhlich of the Centre for the Proper Housing of Poultry and Rabbits (ZTHZ) in Zollikofen in Switzerland.

He was making the first presentation at a conference 'Alternative Systems for Poultry – Health, Welfare and Productivity', which was held in Glasgow, Scotland in September, organised by the UK Branch of the World's Poultry Science Association (WPSA). The conference, the 30th in the series, was attended by more than 120 delegates from 26 countries, including Australia, the US, Africa and the Middle East.

For both meat- and egg-type birds, flock sizes increased from the 1960s and production systems, for hygienic and economic reasons, became more intensive, continued Dr Fröhlich. Rearing and housing of laying hens took place in conventional (battery or unfurnished) cages, while broilers were kept on the floor, systems that have become so familiar across the world.

However, at the same time, public concern for intensively housed birds began to increase, particularly following publications such as 'Animal Machines' by Ruth Harrison in 1963.

As a result, new animal protection laws came into force and agriculture became under increasing pressure to adapt to the welfare concerns of consumers, said Dr Fröhlich.

Alternative systems for housing laying hens have gradually become more popular. They provide greater freedom of movement and facilities for expressing the birds' natural behaviour, including the addition of the 'third dimension' for perching and nesting.

For laying hens in the EU, conventional cages will cease to be allowed from the beginning of 2012, and this type of housing was already banned in Sweden and Switzerland some years ago.

Explaining the broad types of 'alternative' housing systems for layers, Dr Fröhlich said that the old single-level systems, such as the 'Pennsylvania style' are not ideal from the welfare point of view. Although they provide much more space than a cage and offer feeding and nesting areas, they are arranged in such a way that the birds moving between the areas constantly disturb those resting and bouts of aggression can result.

On the other hand, Dr Fröhlich said that aviaries and multi-tier systems offers separate functional areas in three dimensions and the spatial division of the flock means that conflicts between birds are rare. Proper design and construction are vital, he stressed, so that birds do not become trapped or injured.

A further development of this type of system is the winter garden – a covered and netted area outside the house, with plenty of litter, allowing birds more space during the day and fresh air.

The final step is to allow the birds access to pasture or range outdoors during daylight hours. Dr Fröhlich stressed that this free-range area needs to provide cover with trees, shrubs and/or structures to maximise the number of hens using this area.

Dr Fröhlich sees the winter garden as a good option, offering some of the advantages of free-range without the risks.

He said: "Free-range is a risk; you have predators." The resulting injuries and mortality may outweigh the benefits of the additional space from the welfare point of view.

Turning his attention to broiler production, Dr Fröhlich described the standard system of production as one in a windowless house, with a litter floor, feeders and drinkers.

He said that enrichments can be provided in the form of simple ramps on the floor of the house, which encourage the birds to be more active and offer some shelter beneath. He added that slower growing breeds tend to make more use of these ramps throughout the growing period than the faster-growing ones.

As a further enrichment, newer broiler house may have windows to provide some natural light into the house.

Covered outdoor runs also offer enrichment but they are more suitable for alternative breeds, in Dr Fröhlich's experience.

Production systems for meat birds were introduced that, in addition to higher space allowances, specified maximum rates of growth and feed ingredients.

Free-range systems are rarely for meat birds, apart from Label Rouge production in France and similar schemes.

Dr Fröhlich concluded that time alone will show which type of system for poultry egg or meat production will survive the evolving social and economic pressures on producers and consumers.

October 2011