WHEN sheep producers buy a line of ewes that have NSM on the sale card, they are assuming those ewes are not carrying a lamb.
But that assumption can be well and truly wrong.
There have been a few cases recently where buyers have bid on ewes which were Not Station Mated, only to have them lamb once they got home.
Not all the ewes, but enough to be a pain.
And while that is less than useful for the buyers, there's little that can be done about it.
The definition of Not Station Mated, according to the University of Adelaide, is "usually ewes that have not been joined, and therefore not in lamb".
This description is given to indemnify the vendor from the possibility that a stray ram may have got into the mob and mated with the ewes.
The university's website publishes a glossary of Australian agricultural and farm business terms.
"It's a pretty good definition," according to Andy Madigan, the chief executive officer of the Australian Livestock and Property Agents Association.
"NSM means there has been no organised joining on the property or station, so the rams were not purposely put out.
"But if unbeknowns to the vendor, a ram is in contact with the ewes and then gets out again, and the vendor doesn't see it, then that vendor will still confidently say that the ewes have not had a ram.
"That's why with NSM, no one guarantees that the ewes are empty."
Mr Madigan said there was little recourse for a producer who bought a mob of ewes as NSM, which then started to lamb, apart from through legal channels.
"It's like when you buy anything and it's not what it says it is, that you have some comeback through the Trade Practices Acts," he said.
Talking about NSM is like opening a can of worms, according to Ron Rutledge, Elders' Riverina, North East and Gippsland manager.
Yet the term is consistently used on sale cards to give buyers an indication of the joining status of those breeders.
"NSM means the ewes have not been joined to a ram to the best of the vendor's knowledge," Mr Rutledge said.
"And without being the defender of the station, people or owners, ewes sold as NSM and then lambing does happen more often with breeders from the broader areas because the management there is so much more difficult.
"With the tough seasonal conditions across much of northern Victoria and the Riverina, many breeding ewes have been sent away on agistment, and this has probably added to the problems with ewes sold as NSM but then having lambs."
While agistment proved a good option for many, there are a number of cases where the breeder's own ewes have returned to their home joined by a stray ram, and certainly the same could have happened with ewes they inadvertedly sold believing they were empty.
The crossbred fraternity seems to have their heads around the issue, and Mr Rutledge said it was increasingly common for first-cross ewes to be offered "scanned not detectable", or that the scanning could not show a foetus.
But even that term shows how far the industry has come when talking about joining.
Ewes used to be offered "scanned empty" but this again did not guarantee the ewes were not carrying a lamb because the scanning could have been carried out too early to pick up the foetus.
Hence the new term of "not detectable", which essentially means the pregnancy scanner could not detect a foetus on scanning day.
So how do you know you are getting an empty ewe? This is a hard question but can depend on the reputation of the vendor.
Scanning can give a bit more of a guarantee, and Mr Rutledge said he believed it was generating a premium for first-cross ewes scanned not detectable over ewes which were simply sold as NSM at some of the special feature sales.
That's not the case in the Merino industry yet, but it might become more common if cases of ewes sold as NSM but which then lamb increase.
Scanning costs about 50c/sheep and that's not even a bid at some sales.
It could well provide some additional selling power to some mobs, but it is not an iron-clad guarantee to either vendors or buyers that the ewes they are offering are, indeed, not in lamb.
