The SPCA visited Young's property in May, when she had one male and three female adult cats and five kittens, court documents show.
However, the SPCA inspector said there were no health concerns at the time and all the cats were in normal condition.
They were well handled and friendly and good thought had been put into behavioural enrichment, the inspector reported. They also described the environment as "very clean" with no odour noted or any welfare concerns.
But the neighbours' complaints eventually saw Young accused of breaching an Auckland Council bylaw.
She went to trial before Judge Anna Johns in the Auckland District Court and was found guilty of breaching the bylaw between December 23, 2015 and June 28, 2016.
"I have no doubt that Ms Young is passionate about her cats, that was clear, and
they form an enormous part of her day-to-day life," Judge Johns said.
"However the nuisance has been ongoing for some years and that has had significant impact, particularly on the very close neighbours. It has disrupted sleep, the level of urine odour caused health reactions and family members moved out of one of the neighbour's homes because they could not live with the noises of the cats."
The judge also listened to recordings of the cat noises during the trial and described it as "extremely loud and piercing".
"It was occurring during night hours way above any permissible decibel level," she said.
Because Young continued to breed the cats, Judge Johns said the council was entitled to bring it to an end and granted an injunction.
"I mentioned Ms Young's love of her cats because the conditions of the injunction I intend to impose will mean that she can no longer breed cats," the judge said.
Young was ordered remove all her cats and kittens from her property within 28 days, and any cats still in her care have to be neutered.
Judge Johns convicted Young of breaching the Local Government Act, fined her $2000, and also ordered her to pay $1000 in court costs.
