Posted: 20/06/2014 at 08:50
It is entirely the farmer's responsibility to keep his cows away from other people's property.
Visit him and ask him either to put up an electric fence or a permanent fence.
If his cows have damaged the wall it is his responsibility to repair it. At his expense. If he will not do so get it repaired and send him the bill. The small claims court is available to you. But do make sure you have something in writing or he will claim you never complained.