The relative fertility of Thoroughbred stallions is highly variability, ranging from 35% to 90%. Owing to the relatively short 4-month breeding season, and the 14-day delay between breeding and pregnancy diagnoses, breeders require a method to rapidly identify ejaculates that are unlikely to achieve a pregnancy. Stallion fertility is dependent upon the sperms’ ability to efficiently produce energy. We have exploited this biochemical pathway to design and developed a prototype device, named ‘Equility’, that measures the energy producing capacity of spermatozoa in a post-breeding ‘dismount’ semen sample.

Field trials showed that ‘Equility’ readings were significantly higher in samples that achieved a pregnancy, compared to those that did not. This is the first device of its kind that delivers high-quality, biologically meaningful science on-farm, without the need for specialist expertise or prohibitively expensive equipment. Adoption of ‘Equility’ into the breeding shed will enable managers to make informed decisions about strategic breeding practices (such as cross-covering mares in the same oestrous cycle) to increase conception rates. This will greatly reduce the economic costs associated with breeding, while also improving the welfare of Thoroughbred horses.

However, COVID-associated travel restrictions and delays in the availability of prototype components meant that we have not yet been able to conduct the large-scale field trials necessary to validate the efficacy of Equility, prior to moving towards commercialisation. This project, therefore, is centred on two field trials, with the aim to 1) improve the prognostic value to Equility by incorporating a potential measure of ejaculate volume, and 2) to validate that the cross-covering practices, guided by Equility readings, improve conception rates. Once successful, we will move toward commercialisation of Equility, which will include IP protection and licencing. We will select an external veterinary pharmaceutical company to produce and distribute Equility around the globe.