Assessing whether a ewe is fit to join prior to the joining period is a tool more farmers could use to improve ewe and lamb survival and productivity.
The success of reproduction in a sheep operation is a combination of the conception rate and lamb survival and if producers are joining ewes that are a high risk, this can drop profitability quickly.
Pre-joining assessments and culling high risk ewes is an easy and effective way to improve the reproductive ability of the flock. With unfit ewes being four times less likely to join, lambs from these unfit ewes that were able to fall pregnant had a higher risk of dying.
Ballimore-based sheep and cattle scanner Andrew Shearman said producers should not be scared to cull ewes even if their numbers are down.
"They might be in lamb but then have a bad udder, she has a runty lamb, she might get mastitis, she loses the wool from fever so the wool is on the ground, she is poor and the lamb is no good," Mr Shearman said.
"I suppose it's about just making money our of your best sheep and not running sheep that aren't profitable, you're the one that has got to look at them.
"If it needs culling, get rid of it," he said.
Read more:
When assessing if a ewe was fit to join, Orana Veterinary Service's Dr Lydia Herbert, Dubbo said there were a few key points to look for.
"Basic points are making sure they are in optimal condition, checking their teeth and mouths to make sure they still have all of their adult teeth and they are well aligned, checking feet to make sure they are able to walk around the paddock adequately and where possible checking their udders," Dr Herbert said.
"Usually in a normal year, things would be starting to dry off so we would be starting to recommend nutritional supplementation however with the year we have had, I would be worries that some of the ewes will be over fat,"
Dr Herbert said her ideal joining condition score is three to four for optimal joining.
"The big concern I have heard a lot of going around is foot abscesses and food issues," Dr Herbert said.
"It is certainly going to affect your girls because they wont be able to get around and eat, and they will tend to be underweight and have a hard time joining."
Along with the risks of loss of body condition, foot health can also lead to predisposition to metabolic disease during late pregnancy.
"Trying to get their feet nice and dry and foot bathing, and trying to find a nice dry paddock which is know is not easy at the moment," Dr Herbert said.
"If you have a major issue in your flock, you need to know that as soon as you can, obviously if you are two weeks out from joining and have 20 per cent lameness across the board that is going to very significantly effect your lambing rates down the track," she said.
Mr Shearman said one factor that needed to be assessed was the age and maturity of a ewe.
"It is just generally they are joining them too early as maidens," he said.
"Just because they have the weight, doesn't mean they are mature, a 45 kilogram sheep in Mudgee is totally different to a 45kg sheep here (near Dubbo) because they are nearly full maturity there at 50kg and out here it can be 60, 70 or even 80.
"When they don't join, generally there is a reason, if you go back through your calendar you can work it out," Mr Shearman said.
Performing general ewe assessments at lamb marking or weaning can be too far out from joining and allows for issues to arise in that time that may not be detected until after joining. It also means producers can't identify all ewes with unsound udders.
Large risks arise from joining these 'unfit' ewes. "They won't get in lamb and then the flow on effects from that when lambs are so valuable at this point in time," Dr Herbert said.
"You may also have subfertility, so instead of having twins you might have all singles."
"As a general rule of thumb it will negatively impact your weaning rates and when every lamb is worth as much as it is, every lamb matters.
"Just making sure they are on a rising plain of nutrition and on good pasture.
Dr Herbert said that after joining, scanning was also an important tool to use.
"Scanning is very valuable tool as well because it allows you to plan ahead as to whether you are going to have a lot of multiples and if you need to care for those differently to the singles and also plan ahead if you have a lot of dry ewes," she said
Mr Shearman suggested producers organise a scanner at the earliest convenience.
"As soon as rams go in, ring a scanner, book a date, or when rams come out, ring a scanner, book a date, while its fresh in the head. Then they have it in the calendar, they have a date, and don't have to chase someone to try and fit them in last minute.
