Bhubaneswar, March 23: Nandankanan zoo authorities have initiated special measures to keep the zoo inmates cool, as the mercury level touches 37 degrees Celsius here.

While the herbivore enclosures are being covered with thatched roofs and the animals being sprinkled daily, non-stop water supply is being given to the water pools inside the enclosures.

"We have changed the animals' diet. We have asked our veterinarians to remain alert in case any problem arises due to the heat," said Nandankanan zoo deputy director Jayant Dash.

A zoo official said the amount of meat served to the carnivores had been decreased to ensure better metabolism while animals such as bears were being served sugarcane juice and watermelons to beat the heat. Herbivores such as deer are also getting watermelons and coconut water.

"Birds are also vulnerable to heat. We are giving them dilute anti-depressants. So far, no heat related casualties have taken place in the zoo," said another zoo official.

The meteorological department has forecast a gradual rise in temperature. "The mercury column may touch 40 degrees Celsius this month. However, occasional thundershower may occur to bring some relief," said an official of the local meteorological centre.

Sources said the zoo authorities would maintain the anti-heat measures throughout the summer. "Earlier, we used to start taking precautions from April. But since the past few years, the temperature has been soaring from March. So, we are taking these steps early," said a zoo official.

The zoo authorities are also excited as Rukmini, a four-year-old lioness, is expected to deliver a cub in the first week of May. Extra care is being provided to the lioness. "We are keeping tabs on the health condition of the lioness. A team of veterinarians has been asked to take appropriate measures to ensure its safe delivery," said a zoo official.