Recommendations from the World Health Organization that farmers stop using antibiotics to prevent illness are not sitting easily with all livestock producer groups.
WHO released its recommendations on antibiotic use Nov. 7 with the goal of helping to preserve effectiveness of the drugs in the face of growing bacterial resistance that could pose a threat to human and animal health.
However, some groups have concerns that failing to provide antibiotics to animals that are under stress and likely to become ill has animal welfare implications and might also lead to the need for stronger treatments later when illness occurs.
“In some cases, illness can be very foreseeable,” said Dr. Reynold Bergen, science director for the Beef Cattle Research Council.
One example is calves entering a feedlot for the first time, commingling with others and undergoing stress from weaning and transport.
“If we can treat these to prevent disease, then we’ll do two things: we’ll reduce the number of animals that do get sick, and also, if some do get sick, they won’t get as sick, so you won’t need as powerful a drug to treat them,” Bergen said.
In its statement, WHO recommended complete restriction of medically important antibiotics in livestock for disease prevention without diagnosis.
“Healthy animals should only receive antibiotics to prevent disease if it has been diagnosed in other animals in the same flock, herd or fish population,” WHO said.
Bergen said meeting that recommendation will be a tricky proposition for cattle producers. He said the industry acknowledges the concern about antimicrobial resistant bacteria and aims for judicious use, but there is an animal welfare aspect involved in preventive treatment.
“When you’ve got conditions where illness is very foreseeable and you don’t prevent it up front, then you’re kind of essentially allowing them to get sick,” he said.
“Then you’re responding to things, and whenever you’re responding, you’re playing catch up. The risk is that there may be more that get sick. The disease could spread further, beyond just the particular group.
“And not only that, if they get sick enough … a drug that might have worked for prevention under the medium importance category may not work anymore. You may need to go to something that’s high importance or very high importance.”
Producers can limit the need for preventive use by preconditioning calves and employing low-stress weaning and handling, he added.
The U.S. based National Pork Producers Council was less politic in its response to WHO’s recommendation against preventive treatment, calling it “ill-advised and wrong.”
“Denying pigs, cows and chickens necessary antibiotics would be unethical and immoral, leading to animal suffering and possibly death, and could compromise the nation’s food system,” the NPPC said in a Nov. 7 news release.
Pork producers understand the issue of anti-microbial resistant bacteria and share WHO’s concern, the release said, and promote responsible use with the goal of reducing the need for antibiotics.
“(WHO’s) call for stopping the use of antibiotics that are critically important in human medicine for treating infected animals is antithetical to pork farmers’ and veterinarians’ moral obligation to care for their pigs,” said the NPPC.
WHO also said antibiotics should not be used for growth promotion.
In Canada, drug manufacturers have voluntarily removed label claims of growth promotion on antimicrobials. As well, research shows growth promotion properties in such drugs have more to do with effect than cause.
“Research tells us that if you’ve got healthy animals, feeding them an antibiotic is not going to make them grow any better or more efficiently,” said Bergen, citing studies by Dr. Kim Stanford of Alberta Agriculture.
“Any growth promotion effect was simply the side effect of the fact that the animals weren’t sick anymore. So it wasn’t cause. It was effect.”
Canada’s chicken industry moved in July to reduce the preventive use of antimicrobials deemed to be of human importance. It vowed to eliminate use of category two antimicrobials, those of high importance in human medicine, by the end of 2018 and use of category three (medium importance) by the end of 2020. The industry said it has already eliminated preventive use of category one, those of very high importance in human treatment.
U.S. Department of Agriculture acting chief scientist Chavonda Jacobs-Young said the WHO guidelines “are not in alignment with U.S. policy and are not supported by sound science.”
She said the organization had “erroneously conflated” disease prevention with growth promotion in livestock.
In last week’s announcement, WHO Director-General Dr. Tedros Adhanom Ghebreyesus said overuse of antibiotics, and the resulting decrease in their effectiveness, poses a security threat if there is a deadly disease outbreak. He called for action in all sectors to turn back the tide of resistance.
“If we don’t tackle this threat with strong, co-ordinated action, antimicrobial resistance will take us back to a time when people feared common infections and risked their lives from minor surgery,” he said in a subsequent news release.
WHO’s food safety and zoonoses director Dr. Kazuaki Miyagishima talked about volume of use.
“Scientific evidence demonstrates that overuse of antibiotics in animals can contribute to the emergence of antibiotic resistance. The volume of antibiotics used in animals is continuing to increase worldwide, driven by a growing demand for foods of animal origin, often produced through intensive animal husbandry.”