According to a scientific report in PLoS ONE, French researchers have mapped the full genetic makeup of the bacterial organisms responsible for contagious equine metritis (CEM). This work will pave the way for further investigation into the disease which should prove of benefit to horse owners and horses in general.
CEM - most contagious bacterial venereal infection of horses
French researchers have mapped the full genetic makeup of the bacterial organisms responsible for contagious equine metritis (CEM).
Contagious equine metritis affects both mares and stallions and is reported to be the most contagious bacterial venereal infection of horses. The disease should be suspected any time several mares develop the clinical signs after having been bred to the same stallion.
In stallions, the contagious equine metritis organism is carried on the external genitalia and may exist in place for years.
The disease is caused by two strains of Taylorella equingenitalis, one sensitive and the other resistant to streptomycin. Infected animals are identified by culturing, and successive negative tests are required after treatment to ensure the animal is negative before breeding.
In January 2012, the research team announced the genetic mapping of Taylorella asinigenitalis, one of the two organisms behind CEM. It follows their work in mapping the genome of the other organism responsible, Taylorella equigenitalis.
For both species, they identified four different secretion systems and several proteins potentially involved in binding and colonization of host cells, suggesting a strong potential for interaction with their host. Taylorella equigenitalis seemed better-equipped than Taylorella asinigenitalis in terms of virulence.
Analysis of the basic nutrition metabolism of both Taylorella species showed that malate, glutamate and alpha-ketoglutarate may be their main carbon and energy sources.
“This is the first molecular characterization of Taylorella genus members, and the first molecular identification of factors potentially involved in T. asinigenitalis and T. equigenitalis pathogenicity and host colonization.
“This study facilitates a genetic understanding of growth phenotypes, animal host preference and pathogenic capacity, paving the way for future functional investigations into this largely unknown genus.”
The researchers, whose findings were published in the open access journal PLoS ONE, were Laurent Hébert, Bouziane Moumen, Nicolas Pons, Fabien Duquesne, Marie-France Breuil, Didier Goux, Jean-Michel Batto, Claire Laugier, Pierre Renault and Sandrine Petry.