An Irish draught horse named Shayne, who was believed to be the world’s oldest horse, was put to sleep last month after a long, happy and healthy life of 51 years.

The DailyMail reports on Shayne, who was put down after a battle with arthritis left him incapable of standing up on his own.

Shayne was living at the 40-acre Remus Memorial Horse Sanctuary in his final days, where he enjoyed up to five hours outside a day, and a healthy diet of four meals daily.

Sue Burton, the founder of the Sanctuary in Essex, England said, “Shayne was a happy horse, a lovely old boy and we are proud to have known him.”

“He was great to own and we are delighted to have had him and we shall miss him dearly.”

Burton attributes Shayne’s longevity to the fact that he had a pleasant personality, and that his previous owners never overworked him.

“He was such a lovely horse with a great character and he showed how good a horse of this age could look,” said Burton.

Shayne, who stood at 15 hands and weighed over 1,050 pounds, was put to sleep after he collapsed on February 22.

Shayne’s remains were taken for cremation at Row Green Equine and Pet Crematorium in Braintree, where he was cremated without fee.

Ella Martin, from Row Green, said, “It was an honor to be asked to collect Shayne.”

“We have worked with Remus Horse Sanctuary for many years and as a token to Sue and her team we offered to cremate him free of charge, a fitting tribute.”

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. Last year, the Guinness World Records team said nobody had laid claim to the title since Badger's death.

Staff at the sanctuary believed Shayne to be 51 based on the date of birth given by his previous owner, and medical checks, which included examining the condition of the horse’s teeth for length, wear, and how deep the grooves are.

As Shayne's birth was believed to be before horse passports were introduced, there would only be paperwork detailing the exact date if he were a purebreed.

A British Horse Society spokesman estimated that Shayne's years made him the human equivalent of more than 100. However, the spokesman said 'the older they get, the harder it is to tell,' especially when horses get past their average life expectancy of early thirties.

On average, every horse year beyond the age of four is roughly the same as 2.5 human years.

Elderly Shayne fell a little way short of laying claim to being the oldest horse in history. That title belongs to 'Old Billy' who was foaled in Woolston, Lancashire and had reached the age of 62 when he died in 1822.