KOLKATA: A third tigress has died within three months at the city's Alipore Zoological Garden on Wednesday, raising questions about the medical care provided to animals at the facility.

According to sources at the zoo, the sub-adult Royal Bengal tigress was suffering from an infection by a haemoprotozoan parasite and admitted to an animal hospital in the city where she died. She would have completed three years in February. The tigress was born at Nandankanan in Odisha and brought to the Alipore Zoo in August 2023. A viscera test will confirm the exact cause of death, sources said.

The infection is caused by blood parasites like Babesia, Theileria, Anaplasma and Trypanosoma. It is transmitted by ticks or biting flies, leading to fever, anaemia and jaundice. These parasites also affect livestock (cattle, sheep, goats) and companion animals (dogs, cats).

The two previous tigress deaths at the zoo occurred within a 24-hour span on September 23-24. One was a 21-year-old white tigress born in Alipore Zoo, while the other -- a 17-year-old -- had been brought from Odisha's Nandankanan Zoo in 2016. Both were reportedly ailing from age-related illnesses and were under veterinary care.

The zoo has been dogged by a series of concerns. Earlier this year, reports emerged of discrepancies in animal sourcing, transfer, and record-keeping, with the Central Zoo Authority (CZA) disputing some of the zoo's records. A separate case on the disappearance of more than 300 animals from the zoo is currently being heard in court.