Mrs Coles said the dogs had killed two sheep and injured two others in attacks over the past three weeks.

"The two dogs responsible for the attacks are highly likely to be unsupervised domestics," she said.

Mrs Coles said she was now on the lookout for the dogs with lambing season only a week away at her property in Emu Swamp Road, east of Orange.

"I have lost two sheep, a lamb and one ewe and two have nasty injuries," she said.

"These dogs must be stopped. They are due to lamb next week and these dogs will just rip through them."

She said after speaking to a tenant who heard the dogs bark and to a veterinarian expert on sheep she said she was convinced they were not wild dogs.

"Wild dogs wouldn't bark," she said.

"They are working in a pair. Great chunks have been taken out of the [sheeps'] back legs.

"The first attack was during sunlight hours and the other about dawn.

"It's almost 99 per cent sure they are domestics and they are just not being kept in their yards. It would only be about an hour they would be out."

She said the dogs were seen fleeing after one attack.

"The dogs are described as a male, possible kelpie/cattle dog cross with a red-coloured head and straw-coloured body. The second is a bitch with signs of previous whelping of a uniform tan colour."

MAP: Where the attacks have occurred ...

Mrs Coles said there was an alpaca with the small flock of 13 ewes and 23 lambs.

"The only things we have to protect us is fox baiting and the alpaca," she said.

Mrs Coles said the sheep were all the "lesser-known Australian breed Polwarth" which are bred for their "lustrous wool."

She said the sheep had now been brought closer to the house on the property after drought conditions had forced her to put them in an outer paddock where there was a little growth of feed.

Mrs Coles said there had been a previous incident of a dog attack in an adjoining paddock but not in the paddock where the sheep were placed before the first attack three weeks ago.

She said she had contacted neighbours at adjoining properties but that had not yielded any information or reports of other attacks.

Mrs Coles said she had reported the attacks to police and to council rangers.