Alliance welcomes cuts in antibiotic use in pig industry but calls for husbandry improvements

The Alliance to Save Our Antibiotics welcomes reductions in antibiotic use that the British pig industry has announced today [1]. According to the latest industry data, which covers 87% of the UK pig industry, antibiotic use per unit of livestock was cut by 28% in 2017 compared with 2016, and by 53% compared with 2015.

Despite the reductions, antibiotic use in the British pig industry remains very high and is significantly higher than in the small number of other European countries that provide similar data. Use per unit of livestock in the UK (131 mg/kg) is nearly 9 times higher than in Swedish pigs (15 mg/kg) and 2½ to 3 times higher than in Denmark (44 mg/kg) and the Netherlands (47 mg/kg). British use also remains significantly higher than in France (104 mg/kg) and Austria (87 mg/kg), but is now less than half of use in the United States (349 mg/kg) [2].

A major cause of high antibiotic use in the pig industry is for treating post-weaning diarrhoea, a frequent occurrence when piglets are weaned too early. According to the National Pig Association, 70-90% of British piglets receive zinc oxide in their feed [3], which also helps control post-weaning diarrhoea and is thought to have a growth-promoting effect [4].

Zinc oxide, however, will be banned in the European Union in 2022. It is being phased 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.

Scientists who carried out one very recent study showing that using zinc oxide in pig feed led to significantly higher levels of multi-resistant E. coli concluded that using zinc as an alternative to antibiotics is “highly questionable and thus inappropriate” [5].

Suzi Shingler, campaign manager for the Alliance of the Save Our Antibiotics, said “Using zinc oxide to reduce antibiotic use is not sustainable, and is actually contributing to the problem of antibiotic resistance. Pig farmers should instead be looking to reduce post-weaning diarrhoea by improving husbandry. This should include moving to later weaning and using breeds of sows that are able to care better for the number of piglets they produce.

Pigs kept in barren housing with high stocking densities have also been shown to be more susceptible to certain viral and bacterial infections which are partly responsible for high levels of antibiotic use in the industry [6]. This shows the importance of providing pigs with improved and enriched housing.”