The Tasmanian Tiger (Thylacine), an extinct(?) Australian marsupial predator has been shown to have favoured small agile prey, which probably weighed under 5kg.
Aussie sheep farmers persecuted the poor beast, claiming it was a massive sheep killer, which led to its probable extinction (there are a few, sparse, unconfirmed sightings of the Thylacine floating around).
Shows how being in possession of sharp pointy teeth and a distinctive pelt gets you lynched by farmers wherever you live!
A big thanks to Cryptozoolgy.com for info on this.