When a stray cat named Dallas was taken to Melbourne's Lost Dogs' Home in February this year, it looked like the end of the line.

Key points: The Lost Dogs' Home's two most senior board members have resigned amid a power struggle

The Lost Dogs' Home's two most senior board members have resigned amid a power struggle A former CEO is facing court after allegedly handing a cat with gum disease to a charity

A former CEO is facing court after allegedly handing a cat with gum disease to a charity The iconic animal shelter has churned through 10 chief executives in just five years

The cat had severe gum disease and was clearly in pain.

It was so aggressive that the vets who assessed it had to wear protective equipment.

Without a willing owner prepared to pay thousands of dollars for surgery, vets determined that euthanasia was the only option.

But Dallas survived and what happened next lifted the lid on a bizarre and bitter power struggle at one of Melbourne's most beloved institutions.

Yesterday, that culminated in the resignation of the home's two most senior board members, while a former chief executive is facing court.

It was the home's interim chief executive, Peter Harrison, who allegedly overruled the advice of his vets in March and saved Dallas' life by handing it over to a charity called Rescued With Love.

Dallas the cat was dropped off at the Centre for Animal Referral and Emergency suffering from mouth ulcers. ( Facebook )

Mr Harrison is now facing two charges under the Domestic Animals Act for allegedly handing Dallas over without paperwork and without being de-sexed.

But at the time, he also faced the fury of his own staff, who vented their anger at their new chief executive at a snap meeting, calling it a "slap in the face" and "absolutely disgusting".

After all, they'd been the target of a four-year-long campaign of criticism by Rescued With Love, over what the group believes is unnecessary euthanasia of animals.

Tumultuous times

Just a month earlier, the home's previous chief executive terminated an agreement to allow Rescued With Love to take animals from the shelter, accusing the group of running an ongoing "derogatory and defamatory" campaign against the home.

It had taken its toll.

Morale at the home was dismal, amid allegations of a toxic work environment.

It had churned through 10 chief executives in just five years, and dozens of senior staff — many of whom quit in frustration and disgust.

More than half the employees working at the shelter in the past year have left.

Donors, too, began abandoning the home, angry at the lack of information about what was going on inside its walls.

Some even wrote the shelter out of their wills.

The Lost Dogs' Home has been in turmoil since at least 2015, when several key staff members left. ( ABC News: Ben Knight )

Pressure from 'no-kill' movement

Many former staff say they were deeply wounded by online attacks from members of Rescued With Love, which has a 'no-kill' philosophy, and has held several vigils outside the home for euthanised animals.

In 2015, it succeeded in pressuring the Victorian Government to launch an investigation, which was unable to determine if euthanasia rates at the home were reasonable.

Since then, the home, which handles more than 17,000 dogs and cats each year, has been steadily reducing the number of animals put down.

But staff who spoke to the ABC say the pressure from the "no-kill" movement has been unrelenting, not just from outside the home, but also from within.

The animal welfare shelter offers animals for adoption as well as vet services and lost pet care. ( ABC News: Freya Michie )

One former senior manager says he was told by the chair of the Lost Dogs' Home, Prue Gillies, that he should treat the president of Rescued With Love, Kae Norman, as if she had the power of a board member, and that any new ideas or projects should be run past her for approval.

Kae Norman told the ABC the allegation was "a load of rubbish", and denied trying to influence the running of the home through her friendship with Ms Gillies.

But it's an allegation she has otherwise done little to discourage.

In a since-deleted Facebook post in November last year, she wrote, "Staff in the LDH call me behind my back the shadow director. I've been called worse".

She went on to say Ms Gillies was "a woman who has only ever wanted serious change for the animals".

"How do I know this? We speak about it constantly," the post said.

Do you know more about this story? Email vicindepth@abc.net.au

Ms Gillies has been a rare constant throughout this tumultuous period at the Lost Dogs' Home, until her shock resignation yesterday.

In 2016, she survived an attempt by rank and file members to vote her out when several board directors produced hundreds of proxy votes at the last minute.

Angry members accused the board of stacking the membership, and called on Ms Gillies to stand down.

The ABC has since learned that more than 300 of those new members were signed up just days before the meeting, and that some had no idea they were even signing up as members, believing instead they were signing a petition.

Lost Dogs' Home chairwoman Prue Gillies survived an attempt by rank-and-file members to vote her out in 2016, but quit yesterday. ( Supplied: Lost Dogs' Home )

The following year, the home's constitution was changed, removing voting rights for members and vesting all voting power in the board.

The 2016 annual general meeting and the mysterious proxy votes are now the subject of an investigation by the Australian Charities and Non-Profits Commission.

Ms Gillies did not respond to a request for comment from the ABC.

Her resignation was announced in a letter from the current chief executive Grant Robb.

"Prue has worked tirelessly for the Lost Dogs' Home overseeing a period of modernisation and financial consolidation during her tenure," Mr Robb said.

"The board moved a unanimous vote of thanks upon her announcement."

It also announced the resignation of the board's acting deputy, Rob Donato, and that the former chief executive Peter Harrison had taken a leave of absence.

His case will return to the Magistrates' Court next week.