Musth

Temporin secretion during musth
A wild Indian elephant in musth
An elephant in musth digging its tusks into the ground
An Asian elephant bull chained during musth, with discharge from the temporal glands.
Elephants in musth fighting each other

Musth or must (from Persian, lit. 'intoxicated') is a periodic condition in bull (male) elephants characterized by aggressive behavior and accompanied by a large rise in reproductive hormones. It has been known in Asian elephants for 3000 years but was only described in African elephants in 1981. There is evidence that similar behaviour occurred in extinct proboscideans like gomphotheres and mastodons.

Elephants often discharge a thick, tar-like secretion called temporin from the temporal gland during musth. Behavioral management for captive bull elephants in musth includes physical restraint and a starvation diet for several days to a week.