A “majestic” 16-year-old white lion who lived at Lincolnshire Wildlife Park has died.
Uganda was put to sleep after his “quality of life started to deteriorate quickly”, the zoo said.
The white lion arrived at the zoo in Friskney, near Boston, along with his brother Pascha six years ago.
The park and the University of Lincoln will monitor Pascha to make sure he does not start struggling following the loss of his brother.
Steve Nichols, the park’s chief executive, said a post-mortem examination had found that Uganda’s pancreas was in a “really bad state”.
He added: “The entire team are obviously gutted we’ve lost an absolute cracking part of our extended family, but we’re so pleased that we got to this before it started to cause him insufferable problems.
“We are a sanctuary [and] none of us likes the idea of losing an animal. We all become very attached to them and it’s always a really hard decision.”
In a statement, the wildlife park said Uganda was a “powerful predator with a deep connection to his brother”.
Mr Nichols added: “Now what we’ve got to do is manage his brother, who has been with him for the last 16 years.
“He’s never been separated from him, and he’s been tending to him.”