Racing board staff visited Prangley's kennels in Clevedon where she trains her four greyhounds on August 12, to interview her about the result.
Prangley declined to have the B sample tested and acknowledged she was responsible for the day-to-day running of the kennels and managed Thrilling Freddy at the races.
After being questioned about the positive test Prangley admitted to regularly smoking methamphetamine, at least three to four times a month, and had used it three days earlier.
"She stated that she never smoked methamphetamine at the kennel facilities and that she wore rubber gloves whilst handling the dogs in an attempt to avoid cross-contamination."
Prangley told RIB staff she had used methamphetamine "on and off" for 16 years but had increased the frequency in the past 12 months.
She consented to urine and hair follicle samples being taken and sent for analysis.
Swabs were also taken from the cab area of Prangley's vehicle used to transport the greyhounds to the races.
While the vehicle was free of drug contamination Prangley's hair tested positive for methamphetamine and her urine was positive for meth and amphetamine.
Prangley submitted she was remorseful. She understood the consequences and accepted she had not only jeopardised the integrity of herself as a greyhound trainer, but also the integrity of the racing industry.
"Although a major wrongdoing on my part, I would like to make it clear that there was no act of deliberation behind the positive drug result for 'Thrilling Freddy'," she said.
"There must have been some form of cross-contamination from my own personal use. This is the last thing I would want for any of my dogs whom I love very much."
After being given credit for taking responsibility for her actions, Prangley was banned from the sport for two years and seven months.
Prangley wanted to slowly transition out of greyhound racing because of her age.
But she doubted she would be able to make a return after serving the disqualification because of health reasons and said it was deeply upsetting to be "going out" on this note.
"I am embarrassed, and I have disappointed myself and those closest to me. This has affected them in more ways than you can imagine."
Thrilling Freddy was disqualified from the race and Prangley was ordered to repay the $10,238 winnings.
The adjudicative committee had regard for the impact the breach had on the public perception of greyhound racing.
"Offending of this nature invariably brings the industry into disrepute and no doubt impacts on trust and confidence in the integrity of racing at every level, particularly so for the betting public who wager on the outcome of races; and other participants who have an expectation of a 'level playing field'."
In August Ethan Toomer was disqualified from the sport for three years after he and his dog Thrilling Stella tested positive for methamphetamine.
Aaron Cross of the Greyhound Protection League said the organisation was concerned regarding conclusions of "accidental transference" as there was no chart or scale that defined the doping levels.
"This seems to be a handy narrative for the racing industry and its vested interest regulators," Cross said.
"How exactly is a class A drug ending up in a dog's urine? I don't accept the accidental transference argument. It simply doesn't add up. It got into that urine somehow. It's not magic."
In August 2021 the organisation presented a petition to Parliament seeking the sport of greyhound racing be outlawed and Cross believes it is the only way forward.
He claimed animals were killed, injured, neglected, abused and drugged for the benefit of gambling.
"The government needs to accept responsibility for its role in enabling this activity, and needs to put in place a plan for phasing out racing while ensuring the safety of its victims trapped in this cycle of harm."
Recently appointed Racing Minister Kieran McAnulty didn't respond to a request for comment.
In September 2021 Grant Robertson put the greyhound racing industry on notice that its social licence to operate was under challenge following a review of animal welfare and safety.
