Save as digital disease pics

Dr Cor Lenghaus
Veterinary pathologist Dr Cor Lenghaus has examined 3500 disease cases in sheep, cattle, horses, pigs, poultry, goats and deer held in the National Registry of Domestic Animal Pathology. This involved the microscopic inspection of an estimated 18,000 tissue slides, the best now chosen for preservation as digital images.

Deterioration of a large and invaluable specialist collection of livestock diseases catalogued on tissue slides is being arrested, with the option available to preserve the best samples via digital imaging.

Animal Health Australia hired specialist veterinary pathologist Dr Cor Lenghaus to review the collection of sheep, cattle, horse, pig, poultry, goat and deer diseases.

Dr Lenghaus has spent two weeks a month since November 2005 examining 3500 disease cases, involving the microscopic inspection of an estimated 18,000 tissue slides.

He culled the best for preservation down to more than 1000 different cases, representing diseases in the seven animal species on 4000 slides.

The original collection, the National Registry of Domestic Animal Pathology, was a farsighted project put together at the Elizabeth Macarthur Agricultural Institute (EMAI), Camden, during the 1980s and ’90s.

It represents a large number of the more common diseases seen at veterinary diagnostic laboratories, augmented by examples of more serious exotic diseases which could threaten Australia’s animal industries.

When first set up, it was envisioned that trainee pathologists and others with an interest could visit the registry to study the collection but time and travel costs made this impractical.

Many laboratories around the country have closed and experienced veterinary pathologists retired but the collection still represented a potentially valuable resource for budding pathologists, many of whom had not had the benefits of a broadly based training program.

Dr Lenghaus has now judged how well each still slide represents the disease condition it was first created to demonstrate, whether there is any obvious damage to the slide or tissue, particularly if the tissue staining has faded and whether the slide is suitable for microscopic photography or digital imaging.

“While many slides were in good condition, about a quarter had suffered from fading, or separation of the tissues from the underlying slide,” he said.

“These problems stemmed from a time when there had been a change in slide preparation technology, with plastic rather than glass cover slips used to protect the tissues.

“While a number of the slides could be replaced from existing blocks of tissue, many are now no longer available and any replacements would need to be sourced from elsewhere.

“The slides will continue to fade and separate,” he said.

High resolution imaging of the material presently stored at EMAI would preserve the collection as electronic data and electronic mailing could then make it readily accessible on line.

Building this new database would take a year or more, to carry out imaging, cataloguing, storage and retrieval.