"It's probably easy to grab a couple of lambs off the roadside and bundle them into a vehicle. But with a large animal you're talking about people who know what they're doing."
But Mr Matthews said it wasn't only stock thefts that were an issue in rural Whanganui. There continued to be opportunist thefts of equipment like farm bikes and fuel.
""There's not a lot you can do unless you come across these people in the act," he said.
"It's an ongoing problem and not so much a seasonal thing. The problem is I don't think it's ever going to go away."
Mr Matthews said if people did see suspicious activity they should take a note of a vehicle's registration plate number and its make and pass that information on to the Police.
A Ministry of Primary Industries spokesperson said there had been a string of cattle thefts across the central North Island this year including parts of Whanganui, Taranaki, Rangitikei and Taihape. A recent example happened in Heads Rd when four steers were butchered and another three needing to be put down.
The Ministry is worried the stolen cattle could end up as illegal homekill meat sales.
"There are numerous health risks associated with these sorts of purchases, because unlike regulated meat, which is purchased from a butcher, it has not been subject to strict hygiene and inspection controls," the spokesperson said.
Stock theft and poaching has been estimated to cost the farming community some $120 million each year and has fuelled the call harsher penalties such as confiscating equipment used in the crime and increase maximum jail sentences to reflect the harm done to farmers, and their vulnerability in remote areas.
While the crime of rustling is classed as general theft, anyone found guilty of selling on the meat black market can be charged under the Animal Products Act, facing up to two years in prison and a fine of up to $100,000.
The Ministry is encourages members of the public to call 0800 693 721 if they have any information or see any suspicious activity involving the slaughtering or processing of animals or sales of homekill.