What cattle do is scratch (5)
I believe the answer is:
graze
'is scratch' is the definition.
(I've seen this before)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for graze that I've seen before include "(Cow) feed; scrape" , "Tend at pasture" , "Eat grass; scrape skin" , "Feed in a pasture" , "Wound on skin" .)