Science - February 9, 2006

‘Do not ban free-range chickens’

Allowing chickens to roam outside freely without a roof over their heads on Dutch chicken farms presents risks to public health and food safety. Chickens could become infected with bird flu and take up too much dioxin. But a ban on free-range chickens is not necessary according to experts from Wageningen UR. There are enough other ways to reduce the risks.

‘It is much too simplistic to ban housing systems intended to promote the welfare of animals because they present increased health risks. It is not possible to guarantee a one-hundred-percent safe product from regular systems either. It is important to inform consumers better, however, so that they can consider both the safety and animal-welfare aspects of a product,’ says Martien Bokma, researcher at the Animal Science Group in Lelystad. She worked on a study of the food safety aspects of animal-friendly housing systems. The results were announced this week.
The study examined the tensions betweens animal welfare and food safety. The most important recommendation is that managers of animal-friendly systems try to prevent contact between farm animals and wild fauna. ‘The isolation of commercially kept animals from wild fauna, in order to prevent the transfer of infectious diseases, should always be the objective. You might consider whether it is responsible to keep poultry in an open-air enclosure in an area where many wild geese also graze.’
The researchers think that the risks of bird flu could be limited by covering such enclosures and closing them off with bird-proof netting. Other options are to intensify monitoring of poultry deaths and egg production in combination with deterring wild fauna. The researchers see keeping poultry inside during high-risk periods only as a supplementary measure.
Layers in an outdoor enclosure can take up dioxin from the ground, which poses a risk to people. ‘By paving the first section of an enclosure and ensuring that the rest of the enclosure is planted with a crop, you can probably sufficiently reduce the uptake of dioxin,’ believes Bokma.
It is also important to keep reminding consumers of their own responsibility when it comes to storing and preparing food. Bokma: ‘I can imagine that some consumers would value an open-air enclosure enough to not mind taking extra precautions in the kitchen. Some people will not have any problems with freezing meat and poultry, not setting a piece of raw chicken next to fresh lettuce, or thoroughly cooking a piece of meat.’
‘For older people or vulnerable groups a small chance of being infected with campylo bacteria may pose an unacceptable risk, but for others it is not such a problem,’ says Bokma.
The research was commissioned by the Ministry of Agriculture, Nature and Food Safety and conducted by researchers of the Animal Sciences Group and the Agrotechnology and Food Sciences Group. / GvM