Three ways to check your ewes are fit to join

An MLA-supported project has delivered new ewe health assessment tools to help producers improve ewe and lamb survival, and realise the potential to increase on-farm profit from $4–$8/ewe.

The ‘Fit to Join – Ewe Assessment Tools’ project (led by Pinion Advisory in conjunction with Livestock Logic, Nilon Farm Health and Hot Tin Roof Communications) developed a series of ewe assessment tools to aid the selection process prior to joining.

The tools can be used to classify sheep that should be kept in the flock for another year or culled. Watch the video below or read on to find out more about the tools.

Assessment is key

Livestock Logic veterinarian Andrew Whale said there are steps producers can take this spring to ensure their ewes are fit to join.

“Prior to this research we found producers were following best practice in terms of nutrition pre-joining and during pregnancy to get optimal lamb survival and good conception rates, but they just weren’t hitting the targets we expected,” Andrew said.

“We developed a simple yet effective ewe assessment tool to identify sheep that are at a high risk of failing to get in lamb, or at a high risk of failing to raise a lamb.”

The project’s key findings include:

• Ewes are 4.4 times more likely to be scanned empty if they are classed as unfit compared to fit.
• Unfit ewes were three times more likely to die between joining and marking compared to fit ewes.
• Lambs had a 21% higher risk of death from scanning through to marking if their mother had a bad udder.

These impacts translated into significant modelled economic benefits for classing and culling ewes as unfit to join of between $4 and $8 per ewe.

The ewe assessment tools look at five criteria, including udder health, body condition, lameness, teeth and age.

“Before initiating the assessment process, it is helpful to have a policy in place to support decisions around keeping or culling individual ewes,” Andrew said.

Here are three tips for ewe assessment:

1. Assess the udder

Any ewe with an udder abnormality is an immediate cull. The decision to keep or cull can be less clear for ewes subject to other risk factors, such as average body condition, lameness or unsound mouth.

“Udder health is a key indicator of a ewe’s ability to successfully rear a healthy lamb. Therefore, ewes with teat damage, lumps or an uneven udder need to be culled,” Andrew said.

2. Assess ewe condition

To improve conception rates, sheep that are failing to thrive in current conditions need to be removed.

“Sheep in poor condition due to lameness, age or poor teeth have reduced ability to consume feed and they’re probably the three common reasons why she won’t get in lamb,” Andrew said.

“This is where our two-strike policy comes into play. If we could find two reasons why a sheep shouldn’t be joined then they were removed from the flock.”

For example:

If an older ewe has a sound udder, is more than half a body condition score lighter than the mob average and her teeth are poor, then she would be considered a cull.

However, if the ewe is in light condition and has no other problems then she can be kept for another year to give her the opportunity to improve.

3. Get your timing right

The timing of the ewe assessment is critical and needs to be done a month after weaning because some ewes will develop mastitis from being weaned.

“Doing this job at lamb marking or weaning doesn’t allow producers to identify all the sheep with bad udders,” Andrew said.

“This job needs to be done separately to wet and drying and marking because half of the sheep with bad udders will be missed.

“We designed the assessment tools around what a producer would be willing to do. With two people and two dogs, up to 2,300 ewes can be assessed per day.”