The Alliance to Save Our Antibiotics welcomes the 17% cut in the year-on-year sales of antibiotics for use in animals, announced today by Defra’s Veterinary Medicines Directorate (VMD) [1]. Major reductions were achieved in pigs (34%) and in chickens (37%) in 2016, partly through improving certain management practices and by vets and farmers committing to eliminate unnecessary use. However, the Alliance is concerned that the industry has also been increasing alternative forms of routine medication which have also been linked to antibiotic resistance, rather than focusing primarily on improving animal health.
Antibiotic use remains highest in the pig industry (183 mg/kg), and is still four times higher per pig than in Denmark (44 mg/kg) and the Netherlands (47 mg/kg), and 12 times higher than in Sweden (15 mg/kg), where pigs are farmed less intensively. The main reason for high antibiotic use in pigs is to treat post-weaning diarrhoea, a frequent occurrence when piglets are weaned too early. According to the National Pig Association, 70-90% of piglets are now receiving zinc oxide in their feed [2], which also helps control post-weaning diarrhoea and is thought to have a growth-promoting effect [3].
Zinc oxide, however, will be banned in 2022. In July, the European Commission decided to phase it out due to concerns that it is not biodegradable, and therefore accumulates in the environment where it is toxic to plants and aquatic organisms. There is also growing evidence that the use of zinc oxide increases the incidence in pigs of the superbug MRSA and of antibiotic-resistant E. coli [4]. The VMD has told the Alliance that they will implement the EU ban, but according to the National Pig Association, the VMD may consider re-licensing the feed additive [5].
Suzi Shingler, campaign manager for the Alliance of the Save Our Antibiotics, said: “Using zinc oxide to cut antibiotic use is not a sustainable solution and contributes to antibiotic resistance. The pig industry is suggesting that a ban on zinc oxide may lead to more antibiotic use again, but that would also be unacceptable. Instead, pig farmers should be looking to reduce post-weaning diarrhoea by improving husbandry, including moving to later weaning and using breeds of sows that are able to care better for the number of piglets they produce.”
Although there have been large cuts in the use of medically important antibiotics in chickens raised for meat since 2012 (approximately 70%), use of non-medically important antibiotics is about 10 times higher and at record levels. The non-medically important antibiotics have growth-promoting effects and help control certain diseases that are widespread in intensively farmed chickens. These antibiotics are not used in human medicine, due to their high toxicity, and are not included in the VMD sales data.
There is some evidence that the use of these toxic antibiotics in chickens may increase resistance to medically important antibiotics in some bacteria [6], however, more research is needed as the evidence is not as strong as for zinc oxide.
A safer, alternative approach, would be to improve chicken health by using slower-growing birds and providing more space for each animal.
Interview with the Experts- Laura Boyle, Teagasc
29th February 2024