"It is not difficult to make microbes resistant to penicillin in the laboratory by exposing them to concentrations not sufficient to kill them. There is the danger that the ignorant man may easily underdose himself and, by exposing his microbes to non-lethal quantities of the drug, make them resistant."
Sir Alexander Fleming, Nobel lecture, 1945
Antimicrobial resistance (AMR) has become a "catastrophic threat which could in 20 years see any one of us dying following minor surgery," according to the Chief Medical Officer. This year has seen the fight against AMR promoted to the top of the agricultural political agenda, with moves such as Arla introducing its Arlagården quality assurance scheme for all its UK producers with restrictions on blanket dry cow antimicrobial therapy and, in the US, several multi-chain restaurants opting to only serve meat which has never undergone antibiotic treatment.
AMR is believed to occur when genetic mutation in a microbe means that it cannot be killed by a prescribed therapeutic concentration of a specific drug, but instead survives to multiply without competition from the susceptible microbes. The risk may be increased where microbes have been exposed to antimicrobials at concentrations lower than the therapeutic dose by, for example, failing to complete the full course or administering sub therapeutic levels due to inaccurate weight estimations, or by feeding waste milk to calves.
The dairy sector is unlikely to be the biggest contributor to the problem and some may think of any future legislation as unnecessary bureaucracy, however farms which adopt best practice will be doing themselves a favour in the long run. Do you find that each time your favourite cow gets mastitis, you find it harder and harder to treat and you’re rapidly running out of options?
Top tips for making more informed treatment decisions include:
Lab testing to identify the specific pathogens present in your herd and make sure you are administering the most effective drug. On-farm bacterial culture is gaining in popularity across the pond, so don’t be surprised if you’re brewing your own petri dishes in the not-too-distant future.
Analysing health records in conjunction with your vet is a useful way of spotting trends and deducing whether a particular management change or treatment strategy is having the desired impact.
It may be obvious but following the instructions on the bottle is critical! Calculate precise dosage rates and weights and stick with the treatment plan, even if you think she’s well on the mend.
Ensure antibiotics are used only when bacterial infection is likely – if in doubt, discuss this with your vet.
On a final note, prevention really is better than cure and early detection is the best form of attack. Boost herd immunity with good nutrition, reduced stress and vaccination. Exploit tools, such as mobility scoring and milk recording, and regularly appraise your system to identify the pressure points on your farm and nip the problem in the bud. Contact us for details of our HowsMyHerd service, providing low