
COULD high antibiotic use in cattle feedlots pose a major risk to human health?
Research from the University of New England (UNE) has suggested so, finding 30 per cent to 75pc of antibiotic resistant bacteria in farm soil fertilised with fresh feedlot manure.
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The new study found feedlots could breed a high amount of the bacteria in their soil, which is then commonly used to fertilise crops.
It said from there, antibiotic resistance could potentially spread to people through skin exposure, inhalation or plants growing in contaminated soil.
Swans Veterinary Services owner Enoch Bergman said research like this was important and could help advance awareness of strategies to mitigate the progression of antibiotic resistance.
But if taken out of context, it could inadvertently reinforce unfair stereotypes about the role of livestock.
Dr Bergman said he firmly believed Western Australian cow/calf, stocker and lotfeeding industries played a miniscule role in contributing to the development of antimicrobial resistance.
"Agriculture has often been a soft target when the alternative of tacking the root of an issue is less palatable," Dr Bergman said.
"In this case, the research is clear, antimicrobial resistance in humans is primarily driven by the large scale use of antimicrobials in humans."
The UNE study suggested the potential for feedlot manure to contribute to human antibiotic resistance was compounded by use of the same classes of antibiotics for humans and animals.
It said levels of the bacteria plunged sharply in manure that was stored for at least five months.
Dr Bergman said such research did have value, as it reinforced what the industry already knew about the value of composting manure cleaned from pen surfaces or washed from trucks.
"Many of my clients already compost all of the material removed from their pen surfaces, eliminating most of the bacteria the researchers are concerned with,'' he said.
"Bacteria and viruses are highly mutable, their exponential reproductive rate allows them to adapt and change under all forms of selection pressure, including antimicrobials or antivirals.
"In the human world, sometimes poor compliance in the patient can exacerbate selection pressure.
"This may be in circumstances where patients begin to feel better and shorten their own course of antibiotics or simply forget to take them in the way they were prescribed."
Many veterinarians promote practices, which may reduce the need for antibiotics.
Management practices are an example of this, including yard weaning or by prescribing vaccines designed to proactively reduce illness.
However, Dr Bergman said if antibiotics were necessary, a successful treatment and welfare outcome was predicted upon good communication between the vet and their client.
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He said this ensured the right antibiotics were prescribed at the right time, in the right way, to the right animals and with the right withhold (window of time between treatment and slaughter).
"By working closely with a veterinary feedlot consultant producers are more likely to administer the right product.
"This improves the welfare of their livestock and the profitability of their enterprise, while protecting the consumer and the reputation of our product simultaneously.
"The lotfeeding sector, led by ALFA, has been on the front foot in working with members to promote the responsible use of antimicrobials on National Feedlot Accreditation Scheme feedlots."
Dr Bergman said livestock veterinarians were only allowed to access a narrow range of antimicrobial therapeutics, chosen carefully in constant negotiation with the human healthcare profession.
He said the World Health Organisation was constantly reviewing and refining its recommendations and veterinarians do their best to work within that advice.
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"If a specific therapeutic - or in some cases a class of therapeutics - are deemed essential for treating human patients, we are no longer allowed access for our bovine patients," Dr Bergman said.
"That is a good thing."
Dr Bergman said it was important to "have a very good relationship with a veterinary feedlot consultant".
By doing so, he said individual feedlots could create living documents detailing the specifics for each individual product in their medicine chest, as well as the best therapeutics to treat individual syndromes.
"The art of veterinary feedlot consulting is tailoring treatment programs to suit individual producer's situations and the livestock they procure," he said.
"If we can prevent disease, everyone within the supply chain is a winner.
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"However, when we need to use antibiotics to treat animals it is imperative that we are doing so with the best balanced outcome for both our animal patient and mankind.
"Western Australians can rest easy knowing we are working hard to protect their health in two ways - with nutritious beef and by integrating good antimicrobial stewardship practices."
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