Credit: iStockNext generation IVF techniques will bring a significant boost for the Australian cattle industry.
A groundbreaking new technique to select embryos for IVF transfer in cattle has the potential to improve Australia’s livestock quality and, in turn, national breeding capacity and industry competitiveness.
Researchers from the Centre for Nanoscale BioPhotonics (CNBP), in conjunction with colleagues at the Davies Research Centre and industry partners, have developed an embryo imaging and selection process that almost doubles predictability rates of IVF success among cattle.
This outstanding outcome surprised even the researchers themselves, says CNBP Chief Investigator and team leader Prof Jeremy Thompson.
‘The prediction capability of determining whether an embryo is good or not was over 90% [in our trials],’ says Prof Thompson, who is also a member of the Robinson Research Institute at the University of Adelaide.
‘That’s why we’re very excited about it — we expected probably around 80% predictive power, but to get to over 90 is quite remarkable.’
Driving IVF in the cattle industry
The CNBP’s approach to improving IVF focuses on automation: the more automated steps in this complex and traditionally unpredictable process, the less the risk of human error — and the higher the chance of success.
This investigation into automated techniques began in 2016, in a bid to improve IVF techniques, and increase the uptake of the procedure among the Australian cattle industry.
To combat a notoriously low IVF pregnancy success rate of just 35-45%, the researchers innovated a new technique to choose the best embryos for transfer back into a surrogate cow, based on imaging and algorithms, which will lift pregnancy rates to around 60% on average.
The team took non-invasive, microscopic images of 7-day-old embryos and analysed them using thousands of algorithms, to test each embryo’s chance of success before implanting them.
These specific algorithms were developed by the team at Quantitative Pty Ltd, a spin-out company from Macquarie University.
‘We’re trying to analyse what it is about the images of embryos that tells us what is going to occur when we transfer that embryo,’ Prof Thompson says.
More than meets the eye
In current IVF procedures, a specialist embryologist will view embryos and select what they consider to be ‘good’ candidates, based on a series of visual cues. This process is highly variable, as IVF embryos are difficult to grade well.
‘That is a method that has been around for years and years — intuitively, embryologists have an idea of what they see under the microscope makes it a ‘good’ embryo,’ Professor Thompson says.
‘We have started from scratch with a system that breaks down images into thousands of components, by using the algorithms. Then we apply them to the outcome we’re looking for, which in our case was pregnancy.’
He says the technique has yielded unexpected outcomes.
‘When an algorithm is applied to an image, the embryos look very different,’ he says. ‘The diversity of the look of the embryo is broader in the IVF embryo, that’s why the technique works well with them.’
This automated technique could also serve to revolutionise IVF for humans. The University of Adelaide has supported trials to apply it to human IVF.
Enormous value for industry
The pilot study was funded back in 2017 by industry peak body Meat and Livestock Australia, amid calls for better reproductive technologies that utilised the best genetics from both bulls and cows. This is the fastest way for improving herd productivity, and IVF offers the most flexible way of capitalising on the best cow genetics.
A 2018 report on this research estimated the direct value to breeders at $30,000 for every 1000 transplanted embryos — and that’s based on a modest 5% improvement in pregnancy rates.
Further research is planned to develop easier-to-use hardware and software for this procedure, in a bid to reduce the costs involved and improve access for wider industry use.
Prof Thompson says the collaboration with Quantitative, other researchers from the Davies Research Centre, and the cattle industry has been incredibly positive, and its benefits will be felt across Australia.
‘Having female-focused breeding is the way forward for making our cattle industry competitive across the globe,’ he says.
‘We can produce more drought-resistant cattle, reduce ethical issues, increase their disease-resistance and increase feed conversion efficiency. It’s good for the industry and for Australia.’
