The world's last surviving male northern white rhino has rallied slightly, days after his carers said his future was "not looking bright".

Sudan, who lives at the Ol Pejeta Conservancy in Kenya, enjoyed a mud bath in the rain on Monday, a spokesman told the BBC.

However, they were still not holding out "big hopes" for a miracle recovery.

The 45-year-old is one of just three remaining northern white rhinos and is the only male.

Attempts to mate him with the two surviving female rhinos failed, however, and an account was created for him on the dating app Tinder last year, not in order not to find love, but to help fund the development of in vitro fertilisation (IVF) for rhinos.

The move won him fans across the world - many of whom were devastated on hearing news of his "ailing condition" last Thursday.

Ol Pejeta's Elodie Sampere, told the BBC the rhino - who is the equivalent of 90 in human years, according to the reserve - had been suffering from bedsores as his mobility decreased, one of which had become infected.

"We are treating his wounds twice a day to avoid the risk of infection and they're getting better," she said on Tuesday. "The sores are being made worse because he lies down too much."

The reserve, which has been caring for Sudan and his two female companions since 2009, keeping them under 24-hour armed guard to protect them from poachers, has accepted the rhino will not be with them much longer.

He had only recovered in the last few months from an infection which took hold late last year.

However, they have been encouraged by Sudan's "lifted spirits" in the last few days.

Sudan's was retired from his role as a potential mate four years ago.

But conservationists hope this does not mean the end for the northern white rhino. The two female rhinos - Najin and Fatu - are far younger, and progress with IVF may mean they are one day able to have their own calves.