Saliva swabs for worm-resistant sheep

Worm resistance could be a new breeding value, as a research project readies itself for market. Curlew Merinos stud co-principal Elise Kealy is one of 30 farmers taking part.

Saliva swabs to cut farm costs and chemical reliance while helping farmers breed worm resistance in sheep could soon be a commercial reality.

A Federation University research project has used saliva collections to measure antibody responses in sheep against worms, which has hit its development and marketing stages.

Curlew Merinos stud co-principal Elise Kealy. Picture: Supplied

Curlew Merinos stud co-principal Elise Kealy, from Edenhope, said they have measured worm egg count for about 20 years, after drench resistance was first found on their farm.

They manage about 17,000 Merino sheep with a stud of 500 ewes, and are one of the 30 participants in the research project.

“Twenty years ago we didn’t have breeding values, but Dad was measuring individual worm egg counts in his rams. Once we got breeding values, we were able to use the raw data to convert it to Australian Sheep Breeding Values, which really sped up our genetic gain” she said.

“A lot of farmers in our area will drench four times a year, and their drenching program would usually include a long-acting, generally pre-lambing. We’re getting away with drenching once a year, and only using short-acting.”

Ms Kealy said they regularly completed drench resistance tests, which showed they no longer had drench resistance in their flock.

“We know wormy sheep have higher mortality, 10 per cent less wool production, a 22 per cent reduction in lactation, 20 per cent lower growth and lower condition score,” she said.

“By having our sheep less wormy less often we are not exposed to those production losses, as well as we save labour and money on drenching.”

Federation University veterinary bioscience senior lecturer Sarah Preston said they tested one stud which showed a faster process and lab tests could measure antibody responses.

She said farmers would be able to select sheep for breeding that would be genetically more-resistant to worms.

“In dry conditions, you cannot get the infection required for the accuracy of the (faecal) test. That is a big problem for many farmers at the moment,” she said.

“One of the advantages of our saliva test is you don’t need to have such a high worm infection because that response comes a lot earlier than the eggs do.”

BeanStalk AgTech has backed the project, which created the Federation University supported SwabTec company to develop and market the test.

Dr Preston said they looked for more participatory farms to validate the product, with a goal of 9000 tests.