An 18-year-old lioness was found dead of cardiac arrest in its enclosure at Jawaharlal Nehru Biological (JNB) Park, popularly known as Bokaro zoo, here on Wednesday morning.

Fondly known as Rameshwari, the last of her kind at the zoo, the lioness was found dead near the walking trail inside its enclosure.

Since 2009, Bokaro zoo has recorded deaths of four lions, including three males and the lioness.

The lioness had no history of disease and the zoo staff were shocked at her death.

“Last night we had given her around 8kg of goat meat, besides pieces of chicken, which it ate normally. There was no sign of any disease. In the morning she was found dead,” said Gautam Chakraborty, a JNB officer.

A post-mortem was conducted to ascertain the cause of death.

Dr Mukesh Sinha, of the district animal husbandry department, performed the post-mortem in the presence of the head of department, BSL (horticulture and zoo), Anil Singh, Chakraborty and other staff.

“Cardiac arrest is the possible reason behind the death of the lioness. There were blood clots found in its heart. The other organs had no symptoms of disease,” Sinha told The Telegraph Online.

However, he ruled out any symptoms of Covid-19 as there was no nasal discharge.

After the post-mortem the lioness was cremated inside the zoo. “The cremation was performed in compliance with all Covid-19 precaution and according to the norms of the Central Zoo Authority,” said Manikant Dhan, the chief of communications, Bokaro Steel plant.

The JNB Park, spread across 126 acres, is owned and maintained by BSL.

Chakroborty said, “Till last evening we spotted Rameshwari wandering in her enclosure. We found her food vessel lying empty as it had eaten all the goat meat given to it last night. The death was a shock for all of us.”

Rameshwari was born in 2002 in Maitri Bagh Zoo of Bhillai in Chhattisgarh.

The lioness was brought with a male partner to Bokaro zoo on December, 2008 in exchange for an antelope and black bucks. Unfortunately the male partner died of disease in 2009.

However, there were two more male lions that had been brought from Maharashtra in 2007 before the arrival of the lioness.

A number of precautions have been taken to protect the animals of the zoo from Covid-19.

The zoo is temporarily closed to visitors, but the staff are constantly monitoring the animals.