Summary

The use of assisted reproductive technologies is prohibited in the Thoroughbred, and historically this has meant that stallion sperm quality cannot be thoroughly assessed prior to breeding the mare. The determination of putative stallion fertility at the time of cover would allow managers to make informed decisions about strategic breeding practices, such as cross covering or alterations in booking schedules, in a timely manner.
Over the last 8 years, the Equine Fertility Research Group in the PRC in Reproductive Science at the University of Newcastle have worked closely with four prominent Thoroughbred stud farms in the Upper Hunter to ascertain which sperm factors are most highly associated with fertility in the Thoroughbred. The major finding of this study was that sperm with a higher metabolic rate were more likely to result in positive pregnancy scans at day 14 post-breeding. On the basis of these findings, we have developed a method to predict the likelihood of pregnancy that has greater prognostic value that any other conventional criteria of semen quality. We have demonstrated and published proof-of-principal studies for this assay and have designed a device which allows the test to be performed on-farm.
We are now ready to construct prototype devices and disseminate them to partner farms for testing, validation and refinement. These assessments will take place on commercial Thoroughbred farms, which will be allocated by PO HVERC. If this innovative device is successful, we shall seek to commercialise it in collaboration with our industrial partners.

Program

Thoroughbred Horses

Research Organisation

The University of Newcastle

Objective Summary

The overall aim of this program of research is to assist the Thoroughbred horse breeding industry by developing strategies to increase reproductive performance and as such, we are directly addressing the AgriFutures objective of improving breeding outcomes.
The major objective of this project is to produce a commercially available device which is capable of measuring the metabolic rate of spermatozoa in a post-breeding ‘dismount’ semen sample to identify samples which are unlikely to produce a pregnancy. This will allow stallion managers to schedule the mare to be re-bred on the same cycle to increase the chance of a positive pregnancy outcome. By increasing per-cycle conception rates, mares will conceive earlier in the breeding season, resulting in earlier foals which will attract higher prices at yearling sales and be more competitive in age-related races.
While the primary objective of developing this device is to improve the efficiency and sustainability of Thoroughbred breeding practices, we anticipate that the device will also become an invaluable tool for use in scientific research, and will find a place on the laboratory bench alongside the microscope and the flow cytometer.
During the course of the project, we will gain valuable insights into the basic biology of the stallion spermatozoon and will be able to investigate potential associations between sperm metabolism and fertility with external factors such as environmental fluctuations, changes to management practices and stallion health. This information will be pivotal in guiding both device modifications and stallion management strategies as the project proceeds.