As Shanghai residents sweat under the scorching sun amid the weeklong heat wave, animals at the city's zoo are enjoying some special treatment.

In temperatures of 37 C, air conditioning is necessary for the penguins even in the partially enclosed environment that is equipped with a cool pool, according to Jin Jun, a penguin keeper at the zoo.

"We hide three air conditioners under the rocks so that people won't see them," she said. Jin added that the spots are the penguins' favorites during summer.

Penguins are fed vitamin tablets to build up a resistance to the hot temperatures during summer. Jin prepares little fish by shoving the tablets into their gills before feeding them to the penguins.

Other animals are also enjoying special treatment.

"We turn air conditioners on longer in the primate enclosure, and we give them ice cream sticks with special ingredients to enhance their resistance," said Bai Jiaming, a spokesman for the zoo. "For those that prefer fruit - like the elephants - we give them more fruit during the summer."

Water-loving animals get a shower every 30 seconds, but the elephants prefer to do it themselves by sucking water into their trunks and spraying it over their backs, said Bai.

- Shi Yingying