Danger Dust

Currently, the most effective tick repellents contain ingredients like DEET and permethrin, which are safe when used as directed but are not benign or ideal, and some people simply don't like to use them.

The sebaceous glands of horses and donkeys create secretions that keep their skin moist and include allomones, or chemical substances that affect the behavior of other plant and animal species. Previous research has shown that ticks that feed off horses but not donkeys will be repelled from horses when the horses' smell is masked using one of the compounds, known as (E)-2-octenal, secreted by donkey skin.