NAVLE® Question of the day

This is flehmen. This is a behavior seen in the following circumstances: normal stallion response to pheromones, normal response of all horses to new smells (even foals do it!), sign of colic, or associated with granulosa cell tumors in mares.

Many other animals also show this response, for example here is a cat doing flehmen.

Image courtesy, Waugsberg.