Conference in One Health EJP Annual Scientific Meeting

June 9^th, 2021

Miguela-Villoldo P., Moreno MA., Aguero M., Dominguez L. and Ugarte-Ruiz M.

Aim: Since the first description of the plasmid-mediated mcr-1 gene in Enterobacteraceae, the European Medicines Agency (EMA) and the Spanish Ministry of Agriculture (MAPA), recommended limiting the use of polymixins in animals, especially
in food-producing animals. Consequently, the Spanish Medicines and Healthcare Products Agency created a strategic plan to reduce the consumption of colistin in the pig industry. This study aims to analyze the evolution and current status of the
prevalence of mcr-1 gene in Spanish food-producing pigs population.
Methods: Samples from the caecal contents of healthy pigs (N=244) were sampled at slaughterhouses in different Spanish regions from January to December 2019. Direct DNA extraction from pig caecal samples was carried out coupled by a real-time
SYBR® Green I PCR assay for quantitative detection of the mcr-1 gene. Statistical analysis was performed using T-Test. Data was previously normalised by logarithmic transformation.
Results: From 244 samples, mcr-1 gene was quantified in 67 (27.5%), with a median of 2.69 Log10 copies/mg faeces. Comparing these data with our previous study (Miguela-Villoldo et al, 2019), where we analysed the prevalence of colistin resistance in pigs
from 2012 to 2017, we noticed a significantly decrease of the mcr-1 prevalence in pigs from the 70% reached in 2015.
Conclusions: The levels of mcr-1 show a declining trend that seems to correlate with variations in colistin sales in Spain, reaching similar values to those obtained in 2012 and 2013. So, the EMA recommendations and the Spanish program are playing an effective role in the fight against colistin resistance in pig production

	Servicio de Zoonosis de Transmisión Alimentaria y Resistencia a Antimicrobianos (ZTA). Centro de Vigilancia Sanitaria Veterinaria (VISAVET). Universidad Complutense (UCM).
	Laboratorio Central de Veterinaria (LCV). Ministerio de Agricultura, Pesca y Alimentación (MAPA).
	Subdirección General de Sanidad e Higiene Animal y Trazabilidad. Dirección General de la Producción Agraria. Ministerio de Agricultura, Pesca y Alimentación (MAPA).
	Departamento de Sanidad Animal. Facultad de Veterinaria. Universidad Complutense (UCM).