Researchers from the University of Melbourne are calling for farmers to send in more maggot samples from fly-struck sheep.
- Researchers need maggots from fly-struck sheep
- The wet summer and autumn has led to more blowflies
- The aim of the project is to manage resistance to blowfly control strategies
The wet summer and autumn that many landholders experienced, particularly during the east coast flooding, has led to more flystrike problems for farmers this year.
Each year blowflies infest the skin and tissue of sheep causing flystrike, resulting in annual losses worth $280 million to the wool industry, and a lot of suffering for infected animals.
In a bid to help combat the problem, University of Melbourne’s Trent Perry and Clare Anstead are studying the genetic variation present in sheep blowfly populations across Australia.
“We want to look at the population structure of blowflies and see how much they move around, and whether there are distinct populations that we need to look at controlling separately or whether there is one larger population and how they move about,” said Dr Perry, School of BioSciences senior research associate.
He said the research, which was funded by Australian Wool Innovation, was also looking at the variation in the genes of maggots and what that can tell scientists about how flies build resistance to chemical treatments.
“We want to see how they work and have a look at changes that people have found that are involved in resistance and check whether or not in limited samples we see those changes,” Dr Perry said.
He said they were also collaborating with the CSIRO to look at a potential vaccine to prevent flystrike.
“We want to make sure they’re not different genes in different populations around the country,” Dr Perry said.
‘Fresh is best’
The research was started in 2019, and this will be the last season for maggot collection.
Parasitology senior lecturer, Dr Anstead, said to complete the project, they needed more maggots.
“As strange as that sounds, we really need maggots from all around the country as we want to test as many different flies from as many different potential populations as possible,” she said.
“We send out maggot collection packs in the post to sheep producers, and all they need to do is scrape them off the sheep, pop them in the tubes and mail them back so we can start our analysis.
Sheep producers were asked to fill out a questionnaire including the breed, if it was a breach or body strike, and if chemical was applied when they send in their samples.
Dr Perry said those details would also be integrated into the study.
More samples were needed, particularly from northern New South Wales and Queensland.
“Flystrike has been much more of a problem this year that it was in the last couple of seasons of collecting samples,” Dr Perry said.
“While we certainly don’t wish flies upon anybody, but given they have been around because of the wet weather, it has been very useful for us to be able to get a wide range of samples.”
Resistance management the end game
The project will be completed by mid-next year.
“Once we get the flies and maggots in, we have to type them, check they’re the right species and send them off for sequencing,” Dr Perry said.
“After that, we go through the analysis process and we’ll be looking at the multiple years of collections we’ve got and then we can get a nice picture of what’s happening.”
Dr Perry said the outcome of the project would be to help inform resistance management strategies.
“If there was a resistance outbreak being able to predict how that may spread will allow growers to adjust some of their chemical or other blowfly control strategies around that,” he said.
To receive a collection kit for maggot samples, contact: [email protected]