Anything fed to animals in the uk legally has to be fit for human consumption. Most animals that are used for meat are regularly wormed, and the cooking process will kill any eggs or larvae. Animals can get worms via fleas and prey, but they can also pick them up by eating grass, as grazing animals do, due to ther animals passing eggs in their faeces. Worm egges and larvae can survive for short periods on damp grass, and may be ingested when the cat eats grass.
