A kitten born with no anus has survived 50 days without a poo and two heart attacks before being found and adopted by one of the vets who operated to save its life.

Little ‘Boninho’ was saved by the animal rights NGO Viva Bicho in the municipality of Santos in the Brazilian state of Sao Paulo after reportedly being born without an anus and suffering two cardiac arrests because of the strain on its system.

The fluffy fighter survived 50 days without defecating and needed urgent surgery to save its life when it was finally found with a swollen belly.

Viva Bicho spokesperson Leila Abreu told the news site G1 that the incident took place when they rescued a pregnant cat and managed to find a temporary home for her.

Abreu said: “As the pregnant cat needed a quiet place to stay, we arranged somewhere for her litter to be born. They were all born well and healthy, but the person looking after them noticed that one of the kittens was getting a big belly.”

NGO volunteers took the kitten to a veterinary clinic where it underwent a series of tests before discovering that Boninho was born without an anus.

The congenital abnormality, known as anal atresia, affects the animal’s health and eventually causes death if not surgically corrected.

Abreu said: “If the procedure is not performed, the intestine ends up bursting inside the animal. So Boninho needed urgent surgery because he was 50 days old, a kitten, and since he was born he has not had a bowel movement, causing two cardiac arrests.

“Nobody noticed before because the kittens’ mother, when she is breastfeeding, has the habit of licking clean the kittens’ faeces herself.”

The NGO spokesperson added: “It was basically plastic surgery performed on him. A vet at this clinic ended up falling in love with Boninho and adopted him.”

Abreu said the kitten is doing very well and is “learning little by little”, adding that he is a “little warrior” and the “most important thing is that his life was saved”.