The control of poultry Salmonella colonisation by vaccination and prophylactic treatment with anti-Salmonella antibodies

The genus Salmonella is second to Campylobacter among organisms that colonise commercial poultry and are of significant public health concern. Therefore, the detection and management of colonised broiler breeders and their progeny is essential. An autologous killed trivalent vaccine (3x108 cfu), based on three Salmonella serotypes (Typhimurium [serogroup B], Mbandaka [C1], and Orion [E]) prevalent in the flocks of Australian poultry companies, was developed using Salenvac® technology. At 20 weeks of age, hens vaccinated at 12 and 17 weeks, and non-vaccinated hens, were challenged (107 cfu) with autologous and heterologous serotypes belonging to serogroups B (Typhimurium and Agona), C (Mbandaka and Infantis) and E (Orion and Zanzibar). Overall, vaccination led to a significant reduction in carriage of Salmonella in vaccinated commercial Cobb hens (P 0.05) could be determined for serogroup E. All vaccinated flocks produced a significant antibody response (P= 0.05) between treatment and control groups. Subsequent horizontal data for vaccinated flocks (2004-2005) showed all had lower colonisation rates (P = 1000 in 40% (n = 12) of immunised chickens showed quicker and significant (P = 0.0002) clearance (Typhimurium colonised at day old), than flocks with low anti-Typhimurium titres. The success of this research resulted in the vaccine being incorporated into a Salmonella control system in commercial broiler breeder production