6 things poultry producers can do to cut antibiotics further

The UK poultrymeat and egg sectors are making clear progress in their ambition to reduce antibiotics use. As the push for further cuts continues, Debbie James gets advice on what more can be done.

The latest figure for the volume of antibiotics used by UK poultrymeat producers sits at 17t/year – a reduction of 4t in 12 months.

For the egg sector, British Egg Lion Council figures for the Lion Code scheme in 2021 show that antibiotics use was below the “1% days treated” target set by the Responsible Use of Medicines in Agriculture Alliance (Ruma).

See also: Salmonella strains poultry farms need to be aware of, and why

Reasons behind falling antibiotics use include producers getting better at animal husbandry, hygiene and stockmanship, says Sara Perez, veterinary director at Poultry Health Services.

Ruma acknowledges that achieving zero use of antibiotics is neither possible nor appropriate across any livestock sector, Mrs Perez points out.

“There will come a tipping point where the journey of reduction changes becomes focused on maintaining responsible levels of use rather than pushing antibiotics use so low that the repercussions would actually be detrimental for the health and welfare of the birds,” she says.

Multiple factors contribute to the use of antibiotics in a flock, but these can’t solely be linked to the presence of specific diseases.

Mrs Perez gives her expert advice on practices that every poultry system can observe to keep antibiotics use to a minimum.

1. Separate dirty and clean areas

The ideal would be no visitors at all, but a farm can’t operate without feed deliveries, egg collections and emergency maintenance work. The farm vet also needs access as required. 

Clearly mark where visitors need to park and where they need to go. Have a barrier system – for instance, if they are directed to an office area, put up barriers so that visitors can’t access the farm without contacting a member of your team.

This is not just about protecting birds from disease that may result in antibiotics use, but protecting the industry from biased and negative publicity from unauthorised members of the public gaining access.

Signage is a must to separate “clean” and “dirty” areas.

2. Consider stocking density

High stocking densities can be associated with wet litter, higher ammonia concentrations and increased foot-pad dermatitis.

There is no single perfect stocking density for layers or broilers – the ideal is different for every farm, as no two farms are exactly the same. Instead, stocking densities are based on the assurance schemes; these may be below what is legally required.

Conventional broilers are therefore stocked to a maximum of 38kg/sq m and free-range broilers and enhanced-welfare broilers to a maximum of 30kg/sq m.

For laying hens, the Lion Code of Practice limits stocking density to 16.5 birds/sq m in the floor of the barn.

While high stocking densities may be a contributory factor in the onset and spread of disease, to significantly reduce the current stocking densities – for instance to 30kg/sq m for conventional broilers – would lead to a big shortage of poultrymeat in the UK. 

3. Never rush to restock

In an ideal world, a two-week empty period would be the minimum standard for meat birds, and longer for laying hens. It depends on the size of the farm, and can be up to a month because all the equipment needs to be removed and thoroughly cleaned.

In the real world, however, a minimum of seven days in broilers is what we should be aiming for.

Lower than seven days may compromise biosecurity as the disinfectants won’t have enough contact time and pathogens could carry over to the next flock, resulting in infection and increased use of antibiotics. 

4. Protect and prevent

Vaccination is a key tool in preventing disease. As well as viral diseases, some bacterial infections such as E coli and salmonella can be avoided through vaccination.

However, it is only effective if it is administered properly, which makes it essential to adhere to guidance from the farm vet.

The full benefit of vaccination is also less likely with poor biosecurity and husbandry, so have protocols in place to address these.

To measure how effective vaccination has been, farmers can use a PCR test to find the vaccine strain, or a blood test to measure antibody response.

One of the vaccinations proven to reduce antibiotics use has been the E coli vaccine in layers.

Although the onset of immunity takes two weeks following vaccination, there can be good results when the repeated use of antibiotics does not stop mortality.

In these cases, the use of the vaccine, together with some changes in the environment, has been shown to reduce mortality.

In the most successful cases, an approximate 50% decrease in mortality is seen – particularly when the vaccination has been supported with products to boost the immune system, and lighting adjustments made in the house if there was pecking involved.

The correct use and administration of viral vaccines, such as infectious bronchitis and Gumboro disease in broilers, is also useful to prevent secondary bacterial infections that appear as a result of a viral infection and reduced immunity in the birds.

By vaccinating well, it is possible to prevent these secondary diseases and therefore further reduce antibiotics use.

5. Feed coccidiostats 

It is sensible to include coccidiostats in feed to keep coccidiosis at bay.

Coccidiostats are animal-only antimicrobials and are not classified as veterinary medicinal products, so their use is not linked to reduction of antibiotics.

However, they are considered antibiotics in some countries, including the US.

Although the World Animal Health Organization has confirmed that coccidiostats have no impact on human health, several countries in Europe are using coccidiosis vaccines, fully or partially, as part of their coccidiosis control programmes.

It is likely, therefore, that there will be some pressure in the UK to consider the use of vaccines in the future as an alternative to coccidiostats in feed.

6. Treat sick birds promptly

Treating a sick bird correctly, as rapidly as possible after symptoms appear, prevents disease spread and more birds succumbing to illness.

This is why it is so important that producers contact their vet when they suspect that there may be disease. Even if there is not, prevention is better than cure.

In routine health checks we have sometimes discovered subclinical disease – meaning disease is present but birds are not showing symptoms.

By treating as soon as the disease is diagnosed, we can limit its spread and the severity of the lesions in the affected birds, so that they recover faster which means using antibiotics for a shorter period.

Not all disease and health issues are, or indeed need to be, treated with antibiotics.

There is no treatment for viral diseases, and Covid has perhaps made it more widely understood that the only way to treat viral conditions is by building up immunity and with prevention through vaccination and good biosecurity.

The ‘three Rs’ of antibiotics use

As well as improved animal husbandry, hygiene and stockmanship, the reduction in antibiotics use has been largely due to the successful implementation by the industry of the British Poultry Council Antibiotic Stewardship Scheme’s three Rs approach: replace, reduce and refine.

This means reviewing the use of antibiotics and replacing them where effective alternatives are available, reducing the number of birds that receive antibiotics through systems based on risk assessment, and by continuing to refine existing strategies, using data collection.