Molecular analysis of leptospires from serogroup Sejroe obtained from asymptomatic cattle in Rio de Janeiro - Brazil reveals genetic proximity to serovar Guaricura

- Hardjo may not be the only important serovar from serogroup Sejroe in bovines.
- Five Leptospira santarosai isolates from sg Sejroe were studied.
- Analysis of secY sequence presented high genetic proximity to Guaricura strains.
- Two different genetic groups are indicated in comparison with previous isolated.
- Guaricura may play an important role on bovine leptospirosis in tropical regions.

Bovine leptospirosis causes substantial reproductive failure in cattle, mainly due to infections with serovar (sv) Hardjo infection. Notwithstanding, other serovars from the serogroup (sg) Sejroe could also have important roles in bovine leptospirosis. The objective was to investigate genetic diversity of serogroup Sejroe isolates obtained from asymptomatic cattle in the state of Rio de Janeiro, Brazil. Urine and vaginal fluid (VF) were collected from clinically healthy cattle immediately after slaughter. Five isolates were recovered and characterized (serogrouping) as belonging to sg Sejroe. Sequencing of rrs and secY genes further identified them as Leptospira santarosai. Analysis of secY sequences indicated a high level of sequence homology to sv Guaricura strains. Based on culture and sequence data, we inferred that other members of sg Sejroe may be important in bovine leptospiral infection, particularly genotypes of L. santarosai serovar Guaricura.