Monday, 4 January 2021
Trainers and veterinarians are warned with respect to the use of Bisphosphonates, such as Tildren, with unpredictable detection periods having recently been established.
The Australian Racing Forensic Laboratory (ARFL) is capable of detecting the presence of bisphosphonates, which are deemed to be prohibited substances when detected in a sample taken from a horse at a race meeting or barrier trial (effective 1 February 2021 for barrier trials). Bisphosphonates are found in several registered and non-registered substances and have an effect on bone metabolism and density, potentially altering the constant homeostasis of bone remodeling that occurs in the athletic horse.
Bisphosphonates are present in the registered veterinary medicines Tildren Injection for Horses (tiludronic acid as disodium tiludronate) and Osphos Injection for Horses (clodronic acid as disodium clodronate), available for use in Australia. Trainers and veterinarians are reminded that any other bisphosphonates, including but not limited to zoledronic acid containing substances, are prohibited at all times.
A recent study has found that tiludronic acid was detected in urine samples several years following its administration and that extended withdrawal times, are at least in part, a result of bone resorption long after administration. Due to their long and unpredictable excretion, their use in racehorses should be avoided.
Further to the above advice, the ARFL has recently detected tiludronic acid at low levels in samples provided by horses previously trained in Europe and the United Kingdom, where the use of Tildren is more common.
Trainers and Owners purchasing horses from these jurisdictions should ensure they perform their due diligence to ensure that any horse purchased has not been administered with such substances, that may result in a sample being provided on a race day or barrier trial to have a prohibited substance detected.
For further information trainers and veterinarians should contact Racing NSW Chief Veterinary Officer Dr Toby Koenig on (02) 9551 7500.