File photo dated December 20, 2007. (UPI Photo/Mohammad Kheirkhah)

CLAYTON, Australia, July 3 (UPI) -- Australian scientists say they have started three-year clinical trials to find a successful vaccine against footrot in sheep.

The trials, funded by $663,000 from the Australian Wool Innovation organization, are taking place at Monash University and the University of Sydney.

"The trials are the culmination of eight years of collaborative work on the pathogenic bacterium which causes footrot, Dichelobacter nodosus," said Professor Julian Rood who is leading the study. "We have determined the bacterium's complete DNA sequence, which was then analyzed to identify proteins that are potentially exposed on the surface of the causative bacterium and therefore more likely to elicit an immune response."

The approach, called reverse vaccinology, identified 90 proteins in the footrot bacterium that are potential antigens for a new cross-protective vaccine.

"This funding will allow us to pinpoint those proteins that will target the disease in a vaccine application," Rood said.

Footrot is a highly contagious disease that attacks the feet of sheep causing severe lameness and loss of body condition. It is prevalent in many countries around the world and, in Australia, the financial impact of the disease on the wool and livestock industry is estimated at $100 million a year.