Question

how did kesavan perform his duties as the temple- elephant

Answer 1

One of the most famous elephant serving Lord Guruvayurwas Keshavan, also know as Gajaräja, or "king of the elephants."
In January 1922, Valiya Raja (King) of Nilambur offered one of his 12 elephants to Lord Guruvayurappa, as a fulfillment of his vow when he got back his entire property intact at the time of the Malabar Mutiny. Aged 10 years, Elephant was named Keshavan. He was noble and kindly, yet mischievous and stupid. To remove his lunacy, he was given butter to eat which was first sanctified (made holy) by the Melshanti (Head Priest) – believed to be an effective treatment for stupidity, and then made to perform bhajan by attending all the 3 siveli (temple functions). All this transformed him into an ideal Deity elephant