Losses to British farmers from theft hit a seven-year high of £50m in 2018, according to NFU Mutual.
A 26% rise in claims for stolen farm vehicles, such as tractors and quad-bikes, to £7.4m last year, was behind the overall increase.
Animal theft claims rose 3.7% to £2.5m in 2018, the company said.
Tim Price, from the NFU Mutual, said: “Farmers and country people are suffering from high levels of anxiety due to repeated thefts by gangs who take advantage of farms’ isolated locations to steal machinery, raid tool stores and even butcher sheep in the fields.
“In a single generation, country people have seen rural crime change from the opportunist theft of a single lamb, to brazen heists of tractors worth over £100,000 and rustlers stealing hundreds of sheep,” Mr Price added.
In July last year, when Leicestershire dairy farmer Jimmy and Esther Pritt were on holiday, a relief worker called to say their Collie-x-Huntaway work dog Rabbit was missing.
Mrs Pritt believes Rabbit, who they valued at between £4,000 and £5,000, was “a rare dog in that she would work for anybody, rustle sheep or cattle, work day or night. From a commercial point of view, she was very, very valuable”.
“It was like a family member was taken,” Mrs Pritt added.
The Pritts have since increased security across their farm following the loss of their farm dog, altering their entrance gates and welcoming a guard dog to their property.
NFU Mutual said some rural communities feel “under siege” by repeated crime activity, but are turning to technology to increase security in their sometimes-isolated locations.
The insurer pointed to innovations such as geo-fencing, which triggers an alarm if tractors go beyond farm boundaries, and livestock marking which puts thousands of micro-dots into their animals’ fleeces, as technology which can help farmers.
“While the rise in the cost of rural theft is a huge disappointment, we are convinced it would be much higher without the investment in rural security by thousands of farmers and higher commitment from many police forces to fighting rural crime,” said Mr Price.