Identification and grouping of Dichelobacter nodosus, using PCR and sequence analysis

Dichelobacter nodosus is the causative agent of ovine foot rot, a disease that is a constant economic burden for many Western sheep ranches. Vaccination is one method of treating foot rot. A higher and more specific immune response is observed when monovalent vaccines are used to treat foot rot, as compared to multivalent vaccines, which incorporate all 10 major New Zealand D. nodosus serogroups. There is no single assay for specifically identifying and grouping D. nodosus for the purpose of incorporating only the desired serogroup(s) in a vaccine. A polymerase chain reaction (PCR)-based assay was used to specifically identify and group D. nodosus from a foot rot lesion. Identification and grouping was determined by predicted fragment size analysis and nucleotide sequence information. The PCR approach vastly improves the accuracy in identifying and grouping D. nodosus from a foot rot lesion.