• Vaccine Name: Brucella abortus S19 vaccine (conjunctival form, vaccine brand B)
• Target Pathogen: Brucella spp.
• Target Disease: Brucellosis
• Vaccine Ontology ID: VO_0009568
• Type: Live attenuated vaccine
• Status: Research
• Host Species for Licensed Use: Cattle
• Preparation: Two-dose conjunctival vaccine from vaccine brand B. (Uslu et al, 2025)
• Description: The vaccine has been used safely for about 100 years; conjunctival form used to provide mucosal immunity and short-term antibody response. Efficacy: No antibody response detected; threshold of 30 ICFTUs observed in one animal. Immune response: No detectable antibody response; rapid decrease in antibody titers compared to subcutaneous vaccines. (Uslu et al, 2025)

Cattle Response

• Vaccination Protocol: 23 calves aged 3 to 4.5 months vaccinated; antibody titers monitored every 21 days until 26-28 months old using RBPT, SAT, and CFT serological tests. (Uslu et al, 2025)
• Immune Response: No detectable antibody response; rapid decrease in antibody titers compared to subcutaneous vaccines. (Uslu et al, 2025)
• Efficacy: No antibody response detected; threshold of 30 ICFTUs observed in one animal. (Uslu et al, 2025)
• Description: 23 calves aged 3 to 4.5 months vaccinated; antibody titers monitored every 21 days until 26-28 months old using RBPT, SAT, and CFT serological tests. (Uslu et al, 2025)