Work Package 2:  Alternative control strategies

Main partners:

  • Anders Miki Bojesen, SUND, Department of Veterinary Disease Biology
  • Peter J. Holst, SUND, Department of International Health , Immunology and Microbiology
  • Camilla Foged, SUND, Department of Pharmacy
  • Luca Guardabassi, SUND, Department of Veterinary Disease Biology
  • Axel Boisen, SCIENCE, Niels Bohr Institute

External collaborators:

  • Marianne Sandberg, Danish Agriculture and Food Council
  • Lis Alban, Danish Agriculture and Food Council
  • Poul Bækbo, Danish Agriculture and Food Council, Pig Research Center
  • Hardy Christensen, Danish Technological Institute

Main objectives:

  1. identify interventions to lower use of antibiotics in live animals (pre-harvest): by novel universal vaccines and eradication of resistant bacteria in chicken flocks at different breeding levels
  2. development of practically applicable and cost effective post-harvest decontamination methods in broiler meat (post harvest)

Task 2.1. Identification of serotype-independent bacterial immunogens
Scientist in charge: PhD-student Fabio Antenucci supervised by Anders Miki Bojesen (IVS)

The aim is to identify immunogens that can induce mucosal immunity against Actinobacillus pleuropneumoniae in a serotype-independent manner. The potential immunogens will be selected from the genomes sequence of a broad number of bacterial strains on the basis of their subcellular localization and predicted ability to induce protective immunity. In vivo expressed immunogens will be selected for optimized exposure to the porcine immune system via a virus vector

Task 2.2. Platform technology for vectored vaccines

Scientist in charge: PhD-student to be employed and supervised by Peter J. Holst (ISIM)

Induction of strong mucosal immunity against Actinobacillus pleuropneumoniae requires adequate exposure of the selected immunogens to the porcine immune system. Genes of candidate immunogens identified in Task 2.1. will be inserted into a porcine adapted adenoviral vector. Replication-effective yet non-pathogenic adenoviral vectors have previously been demonstrated as highly efficient at promoting a strong mucosal immune response, which is crucial when aiming at diminishing the lesions caused by a vigorous pathogens like A. pleuropneumoniae, which can cause mortality within hours.

Task 2.3. Vaccine formulations allowing mass administration

Scientist in charge: Camilla Foged (IF)

To enable economically feasible use of the vaccine in production animals with a low profit margin a formulation permitting aerogen or oral administration will be developed. The adenovirus vectors will be encapsulated in a nano-microsphere which will protect the vaccine from environmentally induced deterioration while at the same time promoting mucosal targeting to ensure exposure of the immunogen to the host and induction of a strong mucosal response to eventually protect the pigs from lesions.

Task 2.4. Identifying alternative sources of exposure of extended-spectrum-beta-lactamace E. coli

Scientist in charge: Lis Alban (Agriculture and Food)

Fighting extended-spectrum-beta-lactamace E. coli (ESBL’s) pre-harvest is currently the most accepted approach among consumers and the stakeholders. However, success at attempts of eradication ESBL’s in broiler chicken in the upper layers of the breeding pyramid has still to be seen. To provide an alternative, we wish to identify other source(s) from which the chicken flocks may be contaminated. By monitoring a number of ESBL-free conventional and organic broiler flocks during an entire production rotation including processing we will identify possible port of entry. DAFC and IVS will collaborate in collection and analyses of samples from broilers, the broiler houses and from the meat. Results will also be used to evaluate sustainable diagnostics and antibiotic policies, and the cost efficiency related to the different solutions and in Microbiological Risk Assessment (MRA), to evaluate the importance of exposure to ESBL’s for human health.

Task 3.2. Post-harvest interventions broilers and pigs

Scientist in charge: Luca Guardabassi (IVS)

Practically applicable and cost effective post-harvest interventions to lower the prevalence of antimicrobial resistant bacteria e.g. ESBL’s in broiler meat may provide an attractive alternative for the production of safe meat in a situation where it is impossible to eliminate contamination pre-harvest. DAFC, TI and IVS, SUND will collaborate on conducting surveys with the aim of investigating decay effects using lactic acids and/or hot water on the presence of ESBL’s in broiler chicken meat. IVS will also explore possible applications of the antibacterial effects of low magnetic fields for ESBL control in the food chain by a pilot study in collaboration with a Danish small enterprise (ELKO) and the Niels Bohr Institute (Science).