A central west NSW greyhound trainer accused of giving a dog alcohol and betting on another dog in a Bathurst race has had all charges against him dropped.

Molong-based Augustus Leslie Weekes had charges against him dismissed at the Orange Courthouse today by Magistrate David Day, who found there was "reasonable doubt" that he gave the dog alcohol.

The court heard phone intercepts in which Mr Weekes and his son Toby discussed plans to give a dog alcohol to slow it down in a race at Bathurst in June 2021.

Under cross-examination, Mr Weekes later told the court he did discuss giving the dog alcohol but never went through with the plan because he "chickened out".

The dog in question was Winlock Lloyd, which was the favourite in the race but finished second to last after colliding with another dog.

When asked about another phone recording after the race in which he told his son he gave the dog a "liqueur", Mr Weekes told the court that was the name he used for a common nutrient mix given to racing dogs.

In handing down his judgement, Magistrate Day said Mr Weekes was an "unsophisticated and unreliable" witness and that some of his evidence was "wholly unconvincing".

The magistrate said the burden of proof was with the prosecution to establish guilt beyond reasonable doubt.

He said in his assessment of the evidence there was still reasonable doubt that Mr Weekes gave the dog alcohol.

Magistrate Day said one of the reasons he made the conclusion was because the stewards on race day inspected the dog and deemed it able to race.

"The inference to draw, on balance, was that Winlock Lloyd [the dog] was not noticeably affected," he said.