Piglet vaccination to reduce antibiotics use

According to the VTT, the vaccine, which is produced in the filamentous fungus Trichoderma reesei, can replace antimicrobial drugs, such as zinc oxide, used in pig production. “The vaccine’s production method has proved to be very effective, and it can also be used in the development of other animal vaccines. The method may be available commercially already in the next few years,” says lead scientist Jussi Joensuu of VTT.

However, it has still to be shown in practice that the vaccine that fights of pathogenic E.coli bacteria is effective and safe and can help to fight the global health threat of antimicrobial resistance (AMR). First animal test were carried out this summer in Belgium. “When administered in drinking water, the vaccine offered protection exactly where it is needed, namely in the intestine. If the vaccine was injected, most of the antibodies would remain in the bloodstream,” says Joensuu.

When still suckling, piglets get enough protection from the sow’s milk. The disease emerges when piglets go from liquids to solids, enabling bacteria to attach to the intestine. At this stage, the piglet’s own antibody production is only starting, and pathogenic bacteria get a foothold in the small intestine leading to diarrhoea. Piglet scour is estimated to cause annual losses up to €2bn globally.

F4-positive enterotoxigenic Escherichia coli (ETEC) strains are a frequent cause of porcine post-weaning diarrhea. Orally administered F4 fimbriae or FaeG, the major subunit and adhesin of F4, induce a protective mucosal immune response in F4 receptor-positive piglets. The anti-FaeG vaccine is administered to piglets in drinking water after weaning. The piglet’s immune system recognises the antigen and starts production of antibodies that prevent bacteria from attaching to the FaeG receptors in the small intestine.

Currently, up to 70% of antibiotics are used on animals, especially farm animals.