Introduction

The invention relates to a mixture of Lactococcus lactis strains engineered to express three different vaccine antigens against strains of E. coli pathogenic for swine. Oral administration to piglets around the weaning would improve intestinal health and specifically prevent the diseases caused by the main pathogenic E. coli serotypes.

Technical features

Escherichia coli infections represent a serious problem in pig farming and lead to a massive use of antibiotics. However, to cope with the spread of microorganisms resistant to antibiotics, EFSA guidelines indicate that their use should be reduced also in intensive farming. The invention, having both a probiotic and vaccinal action, allows the control of piglet E.coli infection without the use of antibiotics. In fact, it is an innovative product in which strains of Lactococcus with probiotic activity are engineered to deliver three different E. coli vaccine antigens to the intestine. The target proteins are expressed both inside the cytoplasm and on the membrane wall, guaranteeing resistance to gastric denaturation. Furthermore the invention does not require specialized labor, since it can be formulated as an edible powder and can be administered with food.

Possible Applications

• Functional and active ingredient in:
  • Diet (pre-starter feed) of the piglet;
  • Preparation of reconstituted milk in delivery room;
  • Preparations for the control of diarrhoea;
• Production of recombinant antigenic proteins.

Advantages

• Dual action: probiotic and vaccine;
• Ease of administration (oral with food);
• Local efficacy in the intestine;
• Multivalence;
• High resistance to stomach acids.