
The monkey looks out from the dark, his emaciated, dirty hands clutching onto the rusted wire which has kept him trapped in this tiny hole for a quarter of a century.

This tiny, damp hole has been his home ever since he was captured in 1991 and turned into a family pet - a spectacle for the neighbours to enjoy in this slum in downtown Bangkok, Thailand.

The rat-infested cage is so small, the macaque's muscles had all but wasted away, leaving the animal barely able to stand.

And here he would have remained, were it not for a passer-by who spotted his mournful eyes, and decided to act.

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Prisoner: Joe the macaque was kept in a tiny cage in a Thai slum by his owners from 1991 until he was finally rescued last week

Survival: The tiny rat-infested cage, which measured just 70 X 70 X 80cms, was crammed in between two buildings

Disgusting: Joe was dehydrated and barely able to stand when he was rescued from the slum by Wildlife Friends Foundation Thailand

Joe, as the monkey has been called, was finally rescued last week after Wildlife Friends Foundation Thailand decided to act.

With only vague details to go on - only that the monkey was somewhere in the slum - the team set out, discovering the poor creature living in some of the worst conditions they had ever seen.

Edwin Wiek, founder of WFFT, wrote on Facebook: 'I have seen a lot of animal suffering in the last 17 years, but I would say that the condition the monkey was kept in was probably in the “Top 10” of most horrible cases.'

But there was worse to come.

'When the owner told us how long he had been in there I was absolutely shocked,' he wrote.

'Joe, as the monkey is called, has been in this hell hole since 1991! That is 25 years…

'No water to drink, in almost complete darkness, alone, in his own and human dirt, "his world" being only 70 x 80 x 80 centimetres for the last 25 years!'

Joe's luck was about to change, however, as the team tracked down his owner and persuaded him to part company with the macaque.

Grim: Joe would no doubt have stayed in the cage for the rest of his life had a passer-by not noticed the horrendous conditions

Freedom: Joe's owner was happy to part company with his pet after he was approached by the wildlife charity

Recovery: Joe is already looking far healthier, just a few days into his new life at the animal sanctuary

Future: He isn't climbing quite yet, but he has been spotted washing and his life expectancy has already improved

Joe - dehydrated, dirty and unable to walk - was sedated, and removed from the slum - allowing the team to reveal the full horror of the rubbish-filled cage where he had spent his years.

It transpired there had been one attempt to rescue him before, but the zoo which came to collect him had apparently asked for $100 a month for his upkeep - an amount the owner could not afford.

This time, the WFFT simply took him to their sanctuary - and the change is already noticeable.

'Joe has been a few days at WFFT now and is starting to move around his cage. He walks around but is not able to climb yet, too weak and without the experience to do so,' Edwin wrote.

'Joe was seen taking a bath in his clean water tub yesterday and has been communicating with his neighbours, other monkeys, whom he hasn’t seen for so long.

'His life expectancy is up to 35 years and we hope he will still have some quality years ahead at our sanctuary.'