Improving diagnosis and preventing pregnancy loss in Australian thoroughbreds

Australia has the second largest thoroughbred breeding industry in the world with 660 stud farms across the country, predominantly in NSW, Victoria and Queensland. These stud farms supply thoroughbred horses to both the domestic and overseas markets. The thoroughbred breeding industry is worth more than $1.16 billion per annum to the Australian economy, and employs close to 8000 people, particularly in rural and regional areas.

Current estimates indicate that more than five per cent of thoroughbred foals are lost pre-term in Australia and little is understood about what causes these pregnancy losses or what conditions might contribute to them.  This lack of understanding makes it difficult to provide a definitive diagnosis or explanation for the loss, and owners and stud managers are unable to take measures to reduce repeat losses from affected mares or prevent further losses in other mares.

The multidisciplinary research team, led by Dr Joan Carrick, Registered Specialist in Equine Medicine, Dr Angela Begg retired veterinary pathologist specialist, and Charles Sturt University epidemiologist Dr Victoria Brookes, will use their findings to develop management strategies to reduce the risk of pregnancy loss and to guide further research.

Dr Carrick said, “Pregnancy loss is an important issue for the thoroughbred industry. It has a devasting impact on the horses themselves and the people who work with them. In addition, some of the diseases that can cause equine pregnancy loss can be transmitted to humans, especially during foaling, and this research is an opportunity to look carefully at these and other emerging diseases.

“In better understanding the risks associated with pregnancy we’ll be able to reduce losses through management and prevention. Plus, we’ll be able to describe new conditions more quickly and get on top of the losses.”

Dr Brookes said that this project brings together pathologists, equine medical specialists and epidemiologists to provide a comprehensive and multifaceted understanding of equine pregnancy loss.

“This research is exciting because it’s multidisciplinary. We’re combining pathology, the causes and effects of equine pregnancy loss, and the epidemiology, the incidence and possible patterns, to ensure we have a holistic understanding and approach to addressing this issue for the industry.”

Dr Brookes said, “On the epidemiology side we are looking at the distribution of equine pregnancy loss across Australia – where they occur, when they occur and what types of mares it’s happening to.”

“Our first step is to establish a baseline, to describe what happens in Australia now. That way we’ll know what to expect across the year, across the whole system.”

“We want to add to the knowledge around the risk factors for equine pregnancy loss, extend our understanding to benefit the welfare of the mares.”

Dr Carrick added the findings will inform the development of management strategies to reduce the risk of pregnancy loss and to guide further research.

“Key to this will be establishing a system for the surveillance of equine pregnancy loss which could provide early warning of an outbreak so that industry losses can be limited.”

Dr Carrick said, “The project will also develop diagnostic criteria tools for all known causes of pregnancy loss and a standardised procedure will be described to investigate all pregnancy losses in thoroughbred mares throughout Australia.”

“These will be supported by training tools for veterinarians and pathologists to improve the diagnostic accuracy of pregnancy loss investigations.”

Australian breeders are urgently awaiting the outcomes of this research to further improve mare welfare and minimise their losses. John Sunderland, Stud Manager, Godolphin Woodlands is one such breeder. He said, “I’m very pleased to hear the wheels are now in motion for this important research.”

“We spend 11 months looking after the mares and their foals in utero and to then lose them at birth is extremely disappointing. We just don’t know enough yet about how and why it happens. There’s information we’re missing that this research will help us find out.”

Mr Sunderland said, “We’re still a little reactive when an outbreak of pregnancy loss happens, and this project gives us an opportunity to be more proactive. If we can make it easier and more cost effective to investigate pregnancy loss, that will have a huge benefit to the industry.

“We can always get better at managing the welfare of our horses. Through this research we’ll understand more about why pregnancy loss is happening and there could be something quite simple that we can do that will make a big difference.”

Read more about the project and register to receive updates from the AgriFutures thoroughbred horses program at agrifutures.com.au/thoroughbred-horses.