Rob, Lynne and Katie McCartney will be offering 130 Poll Dorset rams bred in their Yentrac stud, Tatura, Victoria this spring.
"We are very pleased with their growth especially as it has been a tight season, we feel the quality is improving all the time," Rob McCartney said.
"There is excellent demand for prime lambs and our rams are bred to produce early maturing lambs with quality."
There are 350 Poll Dorset ewes joined in the Yentrac stud with outcross sires purchased from three NSW studs: Springwaters, Boorowa; Hillden, Crookwell and Armdale, Marrar.
The focus is on fertility, carcase, ease of management and docility.
"Our ewes have to produce a live lamb every year to hold their place in the stud," Mr McCartney said.
"The rams and ewes have to be well muscled and length is essential, they need to stand on good legs and feet to carry the weight which is necessary.
"A smooth well blended shoulder is a high criteria for ease of lambing.
"Open heads and points are also things we also put a high emphasis on as well as being covered in a good quality downs type fleece."
Mr McCartney also uses Stockscan to monitor muscle area and fat cover through his flock.
"We have sold rams into numerous studs that have gone on to breed well for their new owners," Mr McCartney said.
"Progeny of flock rams sold have topped regional markets such as Shepparton, Bendigo and Ballarat."
Rob McCartney has been breeding Southdowns for 41 years and although they are mentioned as a heritage breed, he doesn't consider them as such.
"The breed has a place in the prime lamb industry and we keep them for profitability and ease of lambing ability, particularly in maiden ewes," he said.
Selection is based on length of body, muscle and wool.
"I want clean heads, no wool on the ears and if the ewes need wigging they are culled," he said.
"There have been outstanding sales at the regional saleyards and the lambs fit into trade weight/supermarket lamb specifications very well. We have also sold semen to USA and the Southdowns are included in Stockscan program."
Three years ago the McCartney family added a White Suffolk stud to their enterprise to meet client demand.
"We now have 80 ewes in the stud and our selection criteria are the same as for the other studs but with the added criteria that they must have the breed characteristic of the Suffolk," he said.
"The White Suffolk stud is included in Lambplan as well as Stockscan for muscle and fat measurement.
Mr McCartney said all three studs take advantage of the use of AI in the breeding program to access the genetic potential of multiple elite sires.