The last word on old-style cages?

Any possibility that conventional cages might be allowed to continue after 2012 appear to have been delivered a body blow by a major EU welfare report.

But the same document sets out a series of recommendations on everything from manure systems to disease control that could have major implications for the future of free range.

Produced by the European Food Standards Agency the report, The Welfare Aspects of Various Systems of Keeping Hens, will form a major building block in the review of the Welfare of Laying Hens Directive, due later this year, which will shape the future of egg production in Europe.

The EFSA document involved a team of scientists from across Europe examining all the current research into laying systems and while it comes to no single conclusion on conventional cages its recommendations conclusively rule them out.

The key findings are that in all housing systems birds must have nests and litter. Even sham dust-bathing, says the report, does not appear to work although it wants more research on this. In order to minimise bone weakness all systems must also provide space for walking, wing-flapping and “other activities necessary to maintain bone-strength.”

It concludes that stepping up cage space from 450 to 750 square centimetres per bird in furnished cages “appears to be beneficial for welfare, allowing a wider behavioural repertoire with no adverse effects on feather pecking, cannibalism or aggression.” However, it still finds that the behavioural repertoire of birds in furnished cages is still restricted compared to those in other systems. But other recommendations that could, if adopted, have a major impact on free range are:

Ammonia levels

Manure should not be stored in the air space in which housed birds are kept, says the report. This recommendation, with massive implications for the egg industry, reflects concern about the extent to which birds are exposed to ammonia. The scientists say: “The limited information available suggests that high levels of ammonia can have detrimental consequences for hens’ respiratory system and eyes.

“Concentrations of ammonia are generally higher in housing systems with manure composting or open storage of slurry inside the house.” The report says recorded levels of ammonia between 12 and 32ppm have been found in commercial aviary systems and 16ppm in single level non-cage systems.

“Ammonia concentrations above 25ppm may have an adverse effect on the health and production of poultry,” it concludes.

Disease in free range birds

The report says measures should be taken to minimise disease challenge especially in free range birds.

Measures the scientists have in mind are not detailed but they do say: “The risk of disease may be very sensitive to the housing systems or their components. Examples are the presence of litter in floor systems or access to free range areas.”

It says that there have been few studies of this but “there are several recent reports in which non-cage housing systems have been widely introduced and where the incidence of bacterial/protozoa infections (like E.coli) show a marked prevalence in floor kept birds compared with cages.

“Keeping birds outdoors presents a risk of exposure to a greater range of infectious agents compared with birds kept only indoors due, for example, to exposure to wildlife including insect vectors. This generally results in a different panorama of diseases. Probability of exposure will be influenced by management systems. Avian influenza is one example where migrating flocks of wild birds in certain regions may serve as a potential vector to birds kept outdoors. In addition birds kept outdoors are more likely to be exposed to bacteria such as Campylobacter and certain parasites.”

Chemical Hazards

The report highlights higher levels of dioxins and dioxin-like PCBs for eggs produced in free range systems (including organic farming). It says special attention should be given to identifying these sources of exposure and higher levels are most likely caused by soil or shavings which are from wood that has been treated. Scientific models suggest that birds could “bioaccumulate” these compounds into eggs at concentrations exceeding EU maximum levels. It says low background levels as found in rural areas usually originate from long range transport of air pollution.

Bone Fractures

The prevalence of fractures during the laying period appears to have increased dramatically over the past ten years, says the report, and is high even in single level non-cage systems. The problem is worst in conventional cages, it goes on, but “nonetheless breakages in non cage systems still occur at unacceptable levels during lay and depopulation, suggesting that the increase in bone strength is insufficient.”

It recommends that “Extreme care should be taken in handling hens. Proper training, assessment of competence and supervision of staff handling hens should be implemented. Incentives that link proper handling to reduced fracture rate should be developed as a matter of urgency.”

Daily Checks

The report recommends that the daily monitoring of what it calls “zootechnical parameters” like water and feed consumption and egg production should become mandatory. Most producers already carry out such routines to comply with the Lion Code or other assurance schemes. But it also adds in egg shell quality. “Disorders in the crystalline eggshell structure have been shown to be caused by increased stress,” it says. “Infectious bronchitis, egg drop syndrome and Newcastle disease all effect egg structure.”

Pecking

The report says genetic selection programmes should be implemented “as a matter of urgency” to minimise the risk of injurious pecking. Beak trimming should be phased out, but only when suffering caused by cannibalism does not exceed that of the effects of the operation. It is undecided on the potential of alternatives to trimming currently being developed.

On the infra-red system which softens the tip of a chick’s beak so that it simply erodes away the report says: “The manufacturers suggest that treatment and the subsequent experience of the chicks is free of pain but this could be questioned as evidence for it is lacking.” It says studies to compare infra-red, hot blade and laser beak treatments for pain responses and neuroma formation are under consideration. It says that if beak blunting proves effective in small scale studies then much wider research in a commercial setting will be necessary before any judgements can be made.

Pullets

The report recommends that chicks should have access to litter from day one and that where nest boxes are raised off the ground pullets should learn to jump to them in rear.

Pullets should also have access to elevated perches and raised platforms from an early age so that they are better able to use them when housed in laying units.