VTT Technical Research Centre of Finland developed a new type of vaccine which can replace antimicrobial drugs, such as zinc oxide used in pig production. Last year, the European Commission banned zinc oxide in pig product. Hog farmers in EU have five years to phase it out.

“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 Principal Scientist Jussi Joensuu of VTT in a press statement.

According to VTT, the developed vaccine is used to treat diarrhea in weaned pigs, administrated through the water.

“When administered in drinking water, the vaccine offers 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 harmful bacteria — usually E. coli — 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 diarrhea. The piglet suffers, its growth slows down and, in extreme cases, diarrhea causes death.

The vaccine is administered to piglets in drinking water after weaning. The piglet’s immune system will recognize the vaccine molecule and start creating antibodies against the bacteria. The antibodies will prevent bacteria from attaching to the receptors in the small intestine, thereby preventing diarrhea.

Filamentous fungus as the expression system
The background for this development lies in Joensuu’s dissertation in 2006 in which he proved the effectiveness of the vaccine molecule. At that time the idea was to produce the vaccine molecules in transgenic plants, but the method was not commercially viable.

The expression system chosen by VTT was filamentous fungus Trichoderma reesei. The vaccine is produced by means of the fermentation process in a closed bioreactor.

VTT Technical Research Centre of Finland Ltd is one of the leading research, development and innovation organizations in Europe.

Source: VTT Technical Research Centre of Finland, Ltd