8.1.4 What are the general conclusions from the European efficacy trials?

In general, oral vaccination against L. intracellularis has shown to be an economically efficient measure to control Ileitis and to allow a better exploitation of the genetic growth potential of the pig. This is particularly important in view of the phasing out of the few remaining antimicrobials used as feed additives in the EC since January 2006 (EC regulation 1831, 2003). Furthermore, oral rather than parenteral vaccination will reduce the transmission of blood-borne infections such as PRRS via multi-use needles and the reduction of injection site reactions and needles retained in carcasses. It will reduce animal and human stresses, time, labour costs and effort compared to individual vaccination (McOrist, 2004).

Side-by-side trials as well as before-after trials and field observation confirm the efficacy of Enterisol^® Ileitis. Efficacy is furthermore demonstrated in the presence of maternal antibodies when vaccinated in three week old suckling piglets and with the concurrent use of zinc-oxide to a level of 2,500 ppm.

Finally, the observed higher feed intake, adequate feed conversion and low variation within pig groups of the same age are signs of well-being in pigs. In this sense, oral vaccination covers a number of important factors of, and can contribute to, practical animal welfare.