ANTIMICROBIAL resistance is currently a hot topic for discussion but do we have enough sciencebased evidence to defend current working practices? This was the main theme of a panel meeting recently hosted by Vétoquinol and chaired by Professor David Barrett from the University of Bristol. Key academic and clinical experts took part in a debate to coincide with the launch of the new antibiotic Forcyl, for which the company is advocating the controlled use by a single, shortacting injection for the treatment of bovine respiratory disease (BRD) in calves. Forcyl contains marbofloxacin, which is administered by intramuscular injection at 10mg/kg. Dr Henry Giboin described how this newly licensed optimal dose maximises the bactericidal effect against BRD pathogens. “Forcyl was designed with targeted but sustainable therapy in mind. The aim is to treat affected animals early to achieve clinical efficacy and pathogen eradication. By not treating too long, you minimise resistance amongst commensal flora,” he said.
RUMA is the national body in charge of the responsible use of antibiotics and John Fitzgerald, who recently retired from the VMD, will soon become its secretary general. “As it stands at the moment, we all need to work together to reduce antimicrobial resistance (AMR) on farm. That includes farmers, vets and pharmaceutical companies alike,” he commented. “We all appreciate how these products provide economic benefits to farmers and health benefits to both humans and animals. However, we witness what is happening in Holland where vets have to reduce antibiotic usage by 50% over the next two years and need to use diagnostic evidence to support their use, only to know that a serious proactive and collaborative management approach is essential here in the UK. Prescription practices differ across Europe, and Britain does not want to be a scapegoat for the Dutch veal industry.” From a clinician’s perspective, Dr Tim Potter from West Point Veterinary Group spoke about the issues surrounding science and practice. “Commercial reality dictates and more often than not it is not practical to investigate every disease situation ahead of prescribing an antibiotic. However, more drug susceptibility testing would improve our understanding of the amount of AMR already present on a farm. The problem is, how can we differentiate treatment failure from resistance when the disease itself can affect the pharmacokinetics and pharmacodynamics of drugs?”
Back to basics
The RUMA and the BVA guidelines on the responsible use of antibiotics are now well-established; however, Dr Potter also suggested a “back to basics” approach:
- health plans should be referred to at regular intervals;
- vaccine use and good husbandry should be encouraged;
- weight measurements taken – estimates vary enormously;
- treatment protocols should be present and adhered to;
- record keeping – prescription details and volumes to be kept for five years;
- antibiotic use in accordance with the product SPC only;
- on-farm compliance – build farmer attitudes into protocol.
The BVA guidelines highlight that a prophylactic approach to the use of antibiotics for the treatment of BRD should be kept to a minimum and only used where older calves are actually physically in contact with disease. Records listing outcomes should always
be kept. “The regulations will definitely change,” said Mr Fitzgerald, “but there is one thing that is certain, and that is
we need to protect the availability of different antibiotic classes for use in animals. “Minimising the preventive use of antimicrobials is one of the recommendations. The use of medicines should not be a substitute for biosecurity and good farm
Unfortunately, animal use of antibiotics has been and still is an easy excuse for antimicrobial resistance (AMR) in human medicine. There are definitely practical difficulties that exist with regards to preventing AMR,” commented John Fishwick, the BCVA president. “We must engage with the profession and create some evidence-based guidelines to use on farm if we are to defend the current
status quo.” Crucially, these important messages need to be transferred across the whole industry. Catherine Mclaughlin, animal health and welfare adviser for the NFU, emphasised the time pressure on the industry with respect to EU legislation. “As a leading member state, consumers, retailers and the government really need to understand the high standards that are already in place on UK farms and the extent of veterinary involvement. They also need to understand the pressures on the industry before imposing new policy.” In his closing remarks, Professor David Barrett reiterated this message and the need for industry collaboration. “The profession needs responsible and defensible protocols that are science-based to prevent new policy being driven by politics alone.” Professor Barrett will also be chairing the BCVA medicines course on the subject later this year.