The most common and most likely answer to this crossword clue is the 6 letter word CATTLE
I've seen this crossword clue in The Times
C
A
T
T
L
E
More clues leading to the result CATTLE
- Girl Ted clobbered with whip: it prevents stock going missing!
- Follower of W Churchill’s not completely taken stock
- W. Churchill’s successor curtailed part of farmer’s livelihood
- Cows Conservative post-war prime minister lacking in character
- . Neat Conservative PM no longer? Back off!
- They ruminate about ex-PM not reaching a conclusion
- Tom let loose on the ranch
- Farm stock let out by lion?
- Tom let loose to become something on the ranch?
- Moggie let out with other animals
Buddy explains!

The straight part
We know that "part of farmer’s livelihood" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case part of farmer’s livelihood = cattle.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CATTLE mean?
CATTLE noun- Domesticated bovine animals (cows, bulls, steers etc).
- Certain other livestock, such as sheep, pigs or horses.
- People who resemble domesticated bovine animals in behavior or destiny.
- (English law, sometimes countable) chattel
- Used in restricted contexts to refer to the meat derived from cattle.