S Hadar and S Virchow (serogroup C). The onset of immunity is as early as four weeks after second vaccination and the duration of immunity is up to 90 weeks post-second vaccination. The firm stated: "Because of the addition of a serogroup C to the existing Nobilis Salenvac ETC vaccine, MSD Animal Health can offer the broadest protection than any other competitor product, which only has the combination of S Enteritidis and S Typhimurium." The company has recently published results from laboratory efficacy studies that provide the basis of the Salmonella serovar cross-protection, as well as the safety and efficacy of the vaccine under field conditions. The conclusions of both studies showed the vaccine provides "significant protection against all three serogroups (B, C and D) by reducing shedding and organ invasion and this protection lasts up to 90 weeks post-second vaccination".