Antibiotic consumption in livestock worldwide could rise by 67% between 2010 and 2030, and possibly endanger the effectiveness of antimicrobials in humans, according to researchers from Princeton University, the International Livestock Research Institute, the Université Libre de Bruxelles and the Center for Disease Dynamics, Economics and Policy.
Five countries — Brazil, Russia, India, China and South Africa — will experience a growth of 99% in antibiotic consumption, compared with an expected 13% growth in their human populations over the same period, the study authors reported in the journal Proceedings of the National Academy of Sciences. In the United States, antibiotic consumption in animals currently represents up to 80% of total antimicrobial sales.
The study focused on cattle, chickens and pigs, and identified the latter two as the main contributors to antibiotic consumption. The researchers worked from a limited data set of veterinary-antimicrobials sales from 32 countries with developed economies.
Two thirds, or 66%, of the projected global increase in antimicrobial consumption is due to the growing number of animals raised for food production. The remaining third is attributable to a shift in farming practices, with a larger proportion of animals projected to be raised in “intensive farming systems,” or factory farms.