20ml. Vib Shield® Plus L5 can be used to protect the breeding herd against both vibriosis and five common strains of lepto. A single dose 2 – 4 weeks prior to breeding helps stop reproductive diseases that upset breeding schedules. Vib Shield Plus is a vibriosis vaccine that can be given anytime within 12 months prior to breeding. Vib Shield Plus is the best choice for vaccinating bulls due to its long duration of immunity.