After the violent earthquake in the Abruzzo region of Italy in 2016, one research group fitted sensors to various animals on a farm close to the epicentre. Initial findings suggested that the animals had "clearly" reacted a few hours before the next major quake. These observations have not yet been published in any scientific journal.
Sources: Tages-Anzeiger, 20. Mai 2017 / New York Times, 17. Juni 2017