Oral vaccination against swine erysipelas--field experiences in Croatia.

In order to prove the effects of mass application of oral erysipelas vaccine via drinking water, in a farrow-to-finish production unit in Croatia, the growing-finishing animals were divided into 3 groups and treated as follows:--Group 1 (n=199) was vaccinated intramuscularly against swine erysipelas at 1 week and 3 weeks after arrival in the growing-finishing facility with a swine erysipelas bacterin.--Group 2 (n=199) were vaccinated at the same time with an avirulent culture of Erysipelothrix rhusiopathiae oral vaccine through drinking water.--Group 3 (n=200) was not vaccinated. Animals with clinical signs of swine erysipelas, chronic progressive arthritis at slaughter, mortality, average daily weight gain during the growing-finishing phase were evaluated. None of the pigs in the groups 1 and 2 showed clinical signs typical for acute swine erysipelas. Twenty-four of the pigs (12 %) in group 3 had pyrexia and skin lesions typical for swine erysipelas. Fifteen pigs in group 1, 13 pigs in group 2, and 63 pigs in group 3 had chronic progressive arthritis (group 1 and 2 vs. group 3: P < 0.01). No significant differences in mortality were recorded between the groups. Group 1 and 2 had higher (P < 0.05) average daily weight gains compared with the group 3.