The new voluntary standards have the twin goals of phasing out antimicrobial use for growth promotion in food animals and bringing other ‘medically important’ drugs under veterinary prescription.

This will see the demise of ‘over the counter’ antibiotics and more control placed in the hands of specialists through the Veterinary Medicines Directorate (VMD).

It will also rule out antibiotic use for feed efficiency/growth promotion through a voluntary change in labelling.

The guidance document is an invitation for companies to alter labeling to remove the production purposes use, change the marketing status from 'over the counter' to Veterinary Feed Directive when drugs are in feed or water in order to provide veterinary oversight and add, where appropriate, scientifically supported disease treatment (control or prevention) uses.

The key measure in the standards compels drug sponsors to revise appropriate use conditions for ‘medically important’ drugs. These are antimicrobials important for treating human disease.

Dr Russ Daly of South Dakota State University Extension says changes wont be felt at ground level for three years.

This is according to the Food and Drug Administration (FDA), the executive body responsible for issuing the guidelines.

The FDA states that, once a product label is changed: “It will be a violation of the Federal Food, Drug, and Cosmetic Act to use these products in feed for production purposes.”

'Production purposes' constitute adding drugs to feed or water to add weight rather than directly tackle a disease outbreak.

What Impact Will the Guidelines Have?

The FDA believes antimicrobial usage will decrease faster if a voluntary and collaborative approach is used rather than introducing separate laws for each drug.

FDA outreach work indicates a pharmaceutical industry desire to support the antimicrobial reduction effort.

However, the voluntary aspect of the guidelines has led many to question the impact of the changes.

South Dakota veterinarian, Dr Russ Daly, has stressed that changes will be felt at farm level, although will take three years to register.

This also requires FDA consultations with drugs companies to finalise in mid-March.

“Initially, it's the animal health companies that will be adjusting their practices,” explained Dr Daly. “Adjustments that will eventually make their way down to the veterinarians and livestock producers.”

He also said that there was no legal guarantee that labelling would be changed. This was up to individual drugs companies.

The warning for producers is that the 'medically important' list of drugs, while three years off, is long.

Describing the list, Dr Daly said: “It contains older drugs like tetracyclines and penicillin along with classes of drugs that are more critical to human medicine, such as cephalosporins and fluoroquinolones.

“When it comes to growth-promoting antibiotics that fall into this category, it's drugs like tetracyclines, tylosin, and neomycin that will be affected."

This means that chlortetracycline (CTC) crumbles for pigs and calves will have to be obtained after a veterinarian - who knows the farm well - completes a VFD form.

“The form will specify the farm and animals to be treated, the duration of treatment, and which drug is to be used. The feed mill or distributor would need to have a properly completed VFD before they could supply the feed,” said Mr Daly.

However, a degree of flexibility will be offered as to which veterinarians qualify to issue the VFD form.

This will vary from state to state but is essentially designed to offer practical means of authorisation for producers on expansive cattle operations as opposed to compact hog units.

Dr Daly emphasised that does not change the fact that VFDs must come from a veterinarian with the farm under their supervision.

Selective Use

Speaking at the release of the guidelines back in December, FDA director, William Flynn, stressed the need for appropriate selection of drugs.

He said that antimicrobial resistance, while not completely preventable, needs to be slowed down.

By highlighting a list of 'medically important' drugs, the FDA hopes to promote selectivity in the industry. The World Health Organisation first published its criticals list in 2005.

Dr Bernadette Dunham, director of the Centre for Veterinary Medicine said of the FDA guidelines: “This action promotes the judicious use of important antimicrobials, which protects public health and, at the same time, ensures that sick and at-risk animals receive the therapy they need.”

“We realise that these steps represent changes for veterinarians and animal producers, and we have been working to make this transition as seamless as possible."

Further Reading

You can read more on the FDA guidelines by clicking here.