While the wounds of BSE remain raw, researchers in the US reveal that chromosome sequencing could lead to solutions for new tests and vaccines for cattle diseases.

Using a DNA sequence analyser researchers at the Bacterial Diseases of Livestock Research Unit, part of the National Animal Disease Center (NADC) in Ames, US, collaborated with the University of Minnesota to sequence the chromosomes of microbes that cause Johne's disease and bovine brucellosis.

The analyser, operated by ARS veterinary medical officer David Alt, allows unit scientists to perform almost 800 reactions a day and can automatically analyse multiple runs of 96 DNA samples.

Sequencing of Mycobacterium paratuberculosis, a microbe that causes Johne's disease, was led by ARS microbiologist John Bannantine and U-M pathogenomics scientist Vivek Kapur.

Johne's, an intestinal disorder, is found in 7 per cent of beef herds and 22 per cent of dairy herds in the US.

ARS microbiologist Shirley Halling and Kapur led sequencing work on Brucella abortus - a microbe responsible for bovine brucellosis, a highly contagious bacterial disease that induces late-term abortions and infertility in cows, as well as undulant fever in humans.

ARS microbiologist Richard Zuerner is currently sequencing Leptospira borgpetersenii serovar hardjo, a cause of leptospirosis. Leptospirosis causes abortions, stillbirths and weak offspring in cattle and swine, and it can reduce milk production in cows.