KEY POINTS:
Auckland Zoo elephant Kashin may well be New Zealand's biggest loser.
The 38-year-old Asian elephant weighed in at 3251kg yesterday - having dropped a whopping 170kg in a year.
Her stablemate Burma, 24, tipped the scales at a relatively svelte 3080kg, but had packed on 134kg since April last year and was expected to get bigger.
The elephants' weights are in the healthy range.
Zoo spokeswoman Jane Healy said Asian elephants kept growing until they were 25 and weighed around 3500kg.
"They can then go on to put on or lose over the years."
Getting a 3-tonne animal to stand on a scale might sound like a tough ask but Kashin and Burma were tempted on with apples.
The giant vegetarians eat up to 150kg of food a day, including 10kg of fruit and vegetables each and three bales of hay between them.
Ms Healy said as a result each produced around 70kg of elephant poo for the zoo's Zoodoo fertiliser each day.
Not unlike humans who watch their weight, the elephants get regular exercise.
Ms Healy said the pair were walked twice a day through the grounds and did other exercises, including mud wallowing, swimming, leg raises and log rolling. "They love the water, unless it's absolutely freezing."
Kashin, who has arthritis in her legs, was treated with magnetic pad therapy and a special supplement.
Both get daily "rub downs" as part of their exercise plan, to stimulate circulation and get rid of dead skin.
