Producers also reported being verbally abused and intimidated by walkers when they were asked to put their dogs on a lead.
The National Sheep Association (NSA), which surveyed 233 of its members across England, Wales, Scotland and Northern Ireland, found a third of farmers had seen between two and five attacks in one year, while three said they had experienced between 50 and 100 attacks per year and two said they had seen more than 100.
NSA chief executive Phil Stocker said the situation was so bad in some areas farmers had considered giving up their sheep altogether.
“One of our members who farms beside a country park in East Sussex will not leave the farm at holiday times or on weekends because they get so many dog walkers and have experienced a number of attacks.
“I think it is often underestimated the impact these attacks have, not only on the sheep themselves, but on the farmers who have to deal with them.”
Mr Stocker said worryingly, farmers had lost faith in the police and as a result only 37 per cent of members had reported attacks.
Out of the 78 respondents who had reported an incident in the past, the most commonly described result was ‘no outcome’.
It was unusual for incidents to proceed as far as the police issuing the dog owners with a restraining order (3 per cent), a court order (6 per cent) or having the dogs destroyed (6 per cent).
Out of court settlements were slightly more common at 9 per cent.
Mr Stocker added: “There is a reticence among police to take these cases to court and that is resulting in farmers not reporting cases.
“We will be taking our evidence to the police to ensure they take this matter seriously.”
The NSA, supported by Farmers Guardian’s Take the Lead campaign and with sponsorship from The Original Muck Boot Company, will continue to lobby the Home Office to bring in tougher penalties for dog owners whose pets attack livestock.