In 2021, the industry was put on notice by the then-minister in charge after animal welfare concerns increasingly emerged.
A major report in 2017 uncovered "unacceptably high" rates of dog euthanasia as well as high numbers of injuries and unaccounted-for dogs in the industry.
Racing Minister Kieran McAnulty said if greyhound racing became prohibited, a plan would need to be made for the future of the dogs.
Greyhounds as Pets spokesperson Daniel Bohan said finding new homes for the dogs was difficult enough now.
The Racing Integrity Board's greyhound review showed adoption of former racing dogs fell by 14 percent from 2020 to 2022 - from 603 adoptions to 521.
The cost of living was discouraging people from taking on Greyhounds, Bohan said, and so rehoming the entire industry would be a challenge.
"This is not just greyhounds and it's not just New Zealand ... adoption numbers just globally are down.
"If you are then going to add a number of additional dogs that are going to need rehoming then that's a further challenge we're going to need to meet."
But it was not unfeasible, he said.
An independent report - commissioned by the government - by former senior judge Sir Bruce Robertson in 2021 noted there were major limitations to rehoming as a viable "solution" to the industry's issues.
"Many dogs were not suitable for rehoming, due to behaviours that made them unsuitable for pet life and a lack of socialisation training to ameliorate these behaviours at a time when the dog is young enough for these to be effective," he said.
"Furthermore, the negative impacts of racing on overall health often do not present until a dog is settled into a new home."
Sir Bruce also said Greyhound Racing New Zealand's (GRNZ) rehoming programme had been a "flagship policy for the industry credited with increasing the quality of life for many dogs and giving them a second chance".
However, he said they must recognise that "rehoming alone cannot solve the problems created by excessive numbers of greyhounds entering the industry each year".
Since the release of that review, the Racing Integrity Board (RIB) has been giving oversight of GRNZ on the issues raised in the document.
Minister for Racing Kieran McAnulty received subsequent findings from RIB on the future of the industry earlier this year.
They were publicy released earlier this week, with RIB saying the decline in adoptions has resulted in increased waiting times for rehoming.
GRNZ has been trying to boost demand for the dogs by doing marketing campaigns in main centres, but RIB in its report noted they will need to develop other initiatives if this does not work.
"There is an opportunity for GRNZ to take a greater role in co-ordinating the rehoming process and strengthening its relationships with some adoption agencies."
On the other hand, the report highlighted positive work by GRNZ such as increasing rehoming capacity by 84 percent in its Great Mates programme kennels since 2019.
RIB said the minister wanted to discuss the report with key stakeholders over the coming months.
McAnulty said any decisions were unlikely before the general elections in October.
