Mycoplasmology, Bacteriology and Antimicrobial Resistance Unit (MBA) of the Ploufragan-Plouzané-Niort Laboratory

The activities of the Mycoplasmology, Bacteriology and Antimicrobial Resistance Unit cover porcine and avian mycoplasmoses and certain bacterial infections of pigs, poultry or farmed fish such as Streptococcus suis, Actinobacillus pleuropneumoniae, Pasteurella multocida, Escherichia coli, etc. The unit also studies epidemiology and mechanisms of antimicrobial resistance in pathogenic, commensal or zoonotic bacteria in pigs, poultry and farmed fish, as well as those in their environments.

Reference activities

The unit is the National Reference Laboratory for avian mycoplasmosis.

It is also part of the National Reference Laboratory on antimicrobial resistance.

Surveillance activities

The MBA Unit takes part in the monitoring of antimicrobial resistance in pathogenic bacteria of poultry, pigs and farmed fish, as part of the Résapath network, in partnership with ANSES's Lyon Laboratory.

It is also responsible for the annual monitoring of Campylobacter antimicrobial resistance in livestock animals. This monitoring plan is carried out under Implementing Decision 2013/652/EU, which specifies the methods for harmonising surveillance at European level. Sample collection is planned to ensure random non-targeted sampling, representative of French production. From 2021 onwards, sampling will be carried out for pigs and calves in odd-numbered years, and for chickens and turkeys (which were already monitored previously) in even-numbered years.

For each batch sampled by veterinary services at the slaughterhouse, any Campylobacter strains isolated by the approved laboratories are sent to the MBA Unit, which is tasked with determining the antimicrobial susceptibility of the isolated bacteria using a liquid microdilution method based on the CLSI Vet01-A4 standard (CLSI, 2013). The antimicrobials included and the concentration ranges tested are specified in Implementing Decision 2020/1729/EU. The results are published in the journals of the European Food Safety Authority (EFSA), the European Centre for Disease Prevention and Control (ECDC), and the Directorate General for Food (DGAL).

Research activities

The unit's research activities are divided into two areas:               

• bacterial diseases of pigs and poultry: studies on the epidemiology of infections, detection methods, characterisation of strains, means of transmission of infections, pathogenesis of infections and co-infections, as well as health or medical control methods. The main bacteria studied are avian and porcine mycoplasmas, as well as Streptococcus suis and E. coli;
• zntimicrobial resistance in bacteria in pigs, poultry, farmed fish and their environments: through prevalence surveys, development of methodologies for the phenotypic determination of strain susceptibility, studies on the detection of resistance mechanisms, the impact of agricultural or veterinary practices on the selection, transmission, spread or persistence of resistance in animals and in the environment, as well as on alternatives to antibiotics.

Main ongoing research projects

The unit is involved in several projects on the characterisation of pathogenic strains and means of infection control, the antimicrobial resistance of pathogenic bacterial strains (Enterococcus cecorum, S. suis, various species of avian and swine mycoplasmas) or bacteria of aquatic origin (Aeromonas, Vibrio, etc.), and on resistance to critical antibiotics such as the latest generation cephalosporins, fluoroquinolones and colistin. Some projects are also examining the impact or benefits of alternatives to antibiotics (probiotics, vaccination, etc.) in poultry, pigs, fish and shrimps.

Exovirulome (2021-2024)

The secretome of animal mycoplasmas: inter-species comparison, role in pathogenicity and application to diagnostics.

Partner: ANSES (Animal Mycoplasmosis Unit, Lyon Laboratory

Evasion (2020-2022)

Evaluation of the impact of the use of an autogenous vaccine against Streptococcus suis on immunological status and tonsil carriage in sows and their offspring

Partners: ANSES (EPISABE Unit and SPPAE department of the Ploufragan-Plouzané-Niort Laboratory), INRAE, ONIRIS, professionals in the swine industry, veterinary pharmaceutical laboratories.

AquaResist (2018-2022)

Role of integrative and conjugative elements of the SXT family in the spread of antimicrobial resistance genes in fish farming

Partners: ANSES (VIMEP Unit), CNRS, University of Lorraine

SARM2 (2020-2021)

Prevalence study of methicillin-resistant Staphylococcus aureus (MRSA) carriage in farmed pigs

Partner: ANSES (EPISABE Unit)

CAVIAR/CARAPACE (2019-2022)

Enterococcus cecorum: analysis of virulence and antimicrobial resistance

Partners: ANSES (Department for breeding and experimentation in poultry and rabbits), INRAE