My brother had cattle get into his corn feild 2 years back.
He called the sherif and the owner of the cows.
The sherif took a report and my brother told the cows owner call your insurance company ( sherif agreed)
It is the cows owners job to properly fence in any livestock ( Ohio )
A threat of a law suit got a GOOD and quick settelment.
2 months later the cows were in the corn again ,this time the owner got a court date for distruction of privat property and a check from the insurance co.

It's not your job the keep the fence up . IMO
I would sue.

Johnch