Australians train sheep-dung worm-sniffer to nab parasites

An Australian dog has been trained to smell sheep droppings to tell which sheep have parasitic worms.

Australian researchers said the german shepherd's skills would be used to develop an electronic handheld "sniffer" device to detect gastrointestinal nematodes in sheep.

Reliable parasite detectors could save sheep farmers millions of dollars a year, said agricultural scientists at La Trobe University in Melbourne.

Internal parasites are a constant headache for sheep farmers because they can interfere with wool and meat growth, and make the animal weak and susceptible to other diseases. They can even kill.

Anti-parasitic drenches have been the weapon of choice for years, but many parasites have become resistant to the drugs.

In New Zealand, some farmers carry out faecal egg counts, washing parasites out of sheep droppings to gauge the level of infection in their flock so that drenches are only used when strictly necessary.

In Australia, the researchers have tried something different.

"Scents - and the use of sniffer dogs to detect them - are used to determine the presence of a number of substances," said the chief investigator, Associate Professor Mark Sandeman.

In human medical research, dogs have been able to correctly distinguish the breath samples of patients with early-stage lung and breast cancer from the those of healthy people, with about 90 per cent accuracy.

"We set out to ascertain whether the presence of intestinal parasites in sheep could be detected by their scent,' said Professor Sandeman.

The female german shepherd, Seb, has been trained to detect parasite-infected sheep droppings by odour with 80-90 per cent accuracy.

"Just as dogs are trained to detect drugs at airports, we trained Seb to detect parasites," he said.

It was too early to say exactly which chemicals, or groups of chemicals, the dog was sniffing out, but research would now find the differences in chemical "signatures" between infected and uninfected sheep.

The electronic handheld "sniffer", similar to those used in the food- manufacturing industry, would be in prototype form within five years.

Professor Sandeman said he envisaged a farmer holding the sniffer near the rear end of sheep or near its droppings. Eventually the detector might be refined using biosensor technology so sheep could be checked automatically.

An Australian sheep industry research consortium is financing the work.

- NZPA