The use of a Salmonella Typhimurium live vaccine to control Salmonella Typhimurium in fattening pigs in field and effects on serological surveillance

This field study was designed to evaluate the use of a live-attenuated Salmonella Typh1murium vaccine in pigs in respect of efficacy agamst S. Typhimurium at time of slaughter and the effect on serological herd monitoring using a commercial mixed LPS-ELISA. About 1289 slaughtered pigs (805 of non vaccinated groups and 484 of vaccinated groups) were investigated by bacteriological and serological examination (1149 pigs). The study showed the efficacy of an oral vaccination with a live-attenuated Salmonella Typhimunum vaccme in reducmg the number of Salmonella carrying pigs at slaughter without a detectable interference with the serological monitoring of Salmonella (using a cut off at 40% OD level)

Study on the virulence and cross-neutralization capability of recent porcine parvovirus field isolates and vaccine viruses in experimentally infected pregnant gilts

The pathogenicity of two recent German field ISolates of Porcine parvovirus (PPV-27a and PPV 143a) and two vaccine viruses [PPV-NADL-2 and PPV-IDT (MSV)], which are used for the production of inactivated vaccines, was mvestigated by maculation of pregnant sows at day 40 of gestation. Post-infection sera of these sows as well as antisera prepared in rabbits by immunization with the four above-mentioned PPV isolates and with the virulent strain PPV-Challenge (Engl.) were tested for their homologous neutralization activities

Quantitative determination of the challenge strain content of the ileum, caecum and ileocaecal lymph nodes following oral challenge of swine with S. typhimurium PT104

A S. typhimurium challenge model for swine was developed which takes into consideration both clinical changes and the colonization of various organs. Young swine were infected, using bait, with various doses of S. typhimurium DT 104 resistant to nalidixic acid. After infection, the presence of the challenge strain in the ileum, caecum and ileocaecallymph nodes was detennined quantitatively. The level of antibodies in the serum to S. typhimurium was established pre-challenge and 6 days after challenge using ELISA

Salmonella choleraesuis live vaccine strain suisaloral: molecular characterization and differentiation from homologous field isolates

The Salmonella enterica subsp. enterica (S.) live vaccine Suisaloral represents an auxotrophic mutant of a S. Choleraesuis strain which is deficient in adenine synthesis. Based on this auxotrophic marker, an adenine-deficient medium is used to identifY this vaccine strain by its inability to grow in this diagnostic medium. However, the widespread application of a Salmonella live vaccine strain requires additional methods that enable a reliable identification of the vaccine strain, its differentiation from field isolates of the same serovar as well as the proof of its genetic stability during animal and environmental passages. Since molecular methods have proven to be very useful tools for the characterization of Salmonella field isolates (Olsen et al. 1993) but also of other Salmonella enterica subsp. enterica (S.) live vaccine strains such as the S. Typhimurium vaccine strain Zoosaloral H (Schwarz & Liebisch 1994a,b) and the S. Dublin vaccine strain Bovisaloral (Liebisch & Schwarz 1996), four independent molecular methods were used to characterize the S. Choleraesuis live vaccine strain Suisaloral and to differentiate this live vaccine strain from homologous field isolates

The use of a Salmonella Typhimurium live vaccine to control Salmonella Typhimurium in fattening pigs in field and effects on serological surveillance

This field study was designed to evaluate the use of a live-attenuated Salmonella Typh1murium vaccine in pigs in respect of efficacy agamst S. Typhimurium at time of slaughter and the effect on serological herd monitoring using a commercial mixed LPS-ELISA. About 1289 slaughtered pigs (805 of non vaccinated groups and 484 of vaccinated groups) were investigated by bacteriological and serological examination (1149 pigs). The study showed the efficacy of an oral vaccination with a live-attenuated Salmonella Typhimunum vaccme in reducmg the number of Salmonella carrying pigs at slaughter without a detectable interference with the serological monitoring of Salmonella (using a cut off at 40% OD level).</p

Quantitative determination of the challenge strain content of the ileum, caecum and ileocaecal lymph nodes following oral challenge of swine with S. typhimurium PT104

A S. typhimurium challenge model for swine was developed which takes into consideration both clinical changes and the colonization of various organs. Young swine were infected, using bait, with various doses of S. typhimurium DT 104 resistant to nalidixic acid. After infection, the presence of the challenge strain in the ileum, caecum and ileocaecallymph nodes was detennined quantitatively. The level of antibodies in the serum to S. typhimurium was established pre-challenge and 6 days after challenge using ELISA.</p

Study on the virulence and cross-neutralization capability of recent porcine parvovirus field isolates and vaccine viruses in experimentally infected pregnant gilts

The pathogenicity of two recent German field ISolates of Porcine parvovirus (PPV-27a and PPV 143a) and two vaccine viruses [PPV-NADL-2 and PPV-IDT (MSV)], which are used for the production of inactivated vaccines, was mvestigated by maculation of pregnant sows at day 40 of gestation. Post-infection sera of these sows as well as antisera prepared in rabbits by immunization with the four above-mentioned PPV isolates and with the virulent strain PPV-Challenge (Engl.) were tested for their homologous neutralization activities.</p

Salmonella choleraesuis live vaccine strain suisaloral: molecular characterization and differentiation from homologous field isolates

The Salmonella enterica subsp. enterica (S.) live vaccine Suisaloral represents an auxotrophic mutant of a S. Choleraesuis strain which is deficient in adenine synthesis. Based on this auxotrophic marker, an adenine-deficient medium is used to identifY this vaccine strain by its inability to grow in this diagnostic medium. However, the widespread application of a Salmonella live vaccine strain requires additional methods that enable a reliable identification of the vaccine strain, its differentiation from field isolates of the same serovar as well as the proof of its genetic stability during animal and environmental passages. Since molecular methods have proven to be very useful tools for the characterization of Salmonella field isolates (Olsen et al. 1993) but also of other Salmonella enterica subsp. enterica (S.) live vaccine strains such as the S. Typhimurium vaccine strain Zoosaloral H (Schwarz & Liebisch 1994a,b) and the S. Dublin vaccine strain Bovisaloral (Liebisch & Schwarz 1996), four independent molecular methods were used to characterize the S. Choleraesuis live vaccine strain Suisaloral and to differentiate this live vaccine strain from homologous field isolates.</p