The oldest neigh is Essex: Meet Shayne, 51, from Brentwood, the world's most mature nag

Pip, a 24-year-old terrier-whippet cross, became world's oldest dog in December

His mane is tinged with grey and he’d have trouble clearing a fence.

But that’s hardly surprising because at 51, Shayne could be the oldest horse in the world.

The chestnut stallion has lived at the Remus Memorial Horse Sanctuary in Brentwood, Essex, since 2007.

And the elderly nag has some senior company after it was revealed that he lives in the same town as Pip the 24-year-old terrier, who is thought to be the world's oldest dog.

Good innings: Shayne still enjoys a gallop outside his stables in Brentwood, Essex, despite clocking up 51 years as one of the world's oldest horses Happy retirement: Shayne, pictured here with stable-hand Paige Emmins, now enjoys a more leisurely lifestyle in his senior years

Shayne is still happily trotting around his paddock and is in better shape than many of his stable mates, despite having nearly three decades on most of them.

He is believed to have inherited the title of the world’s oldest living horse following the death of the previous holder in 2004.

The 15 hands gelding is now enjoying a laid back retirement with four meals a day at the 40-acre Remus Memorial Horse Sanctuary in Brentwood.

Sanctuary founder Sue Burton said: 'We get people who rescue a horse and they say it is in its 30s and then it knocks them for six when we say we have one in its 50s.

The elderly nag lives on a diet of fibre, alfalfa nuts, sugar beet and chaff

'Shayne is a really good boy. He is still very active - sometimes we forget how old he is.

'I guess his secret to a long life is taking it easy in his old age and enjoying his retirement.'

Shayne was brought to the Remus Memorial Horse Sanctuary in April 2007 after spending many happy years with his previous owner in Chingford, Essex.

He is fed a high-calorie diet consisting of fibre, alfalfa nuts, sugar beet and chaff mixed together and he is also partial to a bit of cabbage to help keep his weight at 480kg.

Despite suffering from some mild arthritis, his health is in good health.

The previous title of oldest living horse in the world was held by Welsh/Arab steed Badger, from Pembrokeshire, Wales, who died aged 51, in in 2004.

Shayne does not have a birth certificate but they were given his birth date by his previous owner and have since verified his age with medical checks.

Sue added: 'Fifteen used to be regarded as old for horses when I started working with them, but research into medicines means they can live much longer now.

'The previous owner brought Shayne to the sanctuary after her other horse died.

'Shayne does not have a birth certificate so we are going by what his previous owner told us - but it all adds up.'

Remarkably, Shayne lives in the same town as Pip, the 24-year-old terrier-whippet cross, who was named the world’s oldest dog in December.

Still going strong: Bizarrely, Shayne lives in the same Essex town as 24-year-old Pip, thought to be the world's oldest dog

Record breaker: Shayne could inherit the title of world's oldest horse after the previous title holder died in 2004, aged 51

Pip unofficially became the world’s oldest canine following the death of a 26-year-old Shiba mix, Pusuke, in Japan.

Equine vet Erik Belloy, 46, from House and Jackson vets in Blackmore, Essex, said: 'Fifty-one is definitely a ripe old age.

'It’s uncommon because ponies tend to live a little bit longer than big horses do.

'Horses do, however, live longer now because of advances in veterinary medicine and the production of their feed.'

Pip with her owner Tiffany Dyer. The highly-trained display hound still performs with 18 other dogs in the Essex Dog Display Team

Royalty: Pip is pictured meeting meeting the Duchess of Cornwall. Her age in human years stands at a jaw-dropping 170 and she will celebrate another birthday in June

A spokesman for Guinness World Records yesterday (Weds) said: 'We have not received any claim for the oldest living horse since Badger’s death and we are really happy to hear about the horse you mentioned.

'The owners could make a claim for the title.'