What’s causing your lamb mortality?
30 July 2015
Are foxes really killing your lambs, or is it actually brain injury during the birthing process? Two workshops at Buraja and Howlong next week may hold the key.
As scanning rates continue to increase, it's not uncommon to hear of landholders who have a weaning percentage 30 or 40% lower than their scanning rates. It's very common to hear these losses blamed on predators, but what really killed these lambs – Foxes? Eagles? Cold weather? Mis-mothering? Dystocia?
Most people might be surprised to learn that the most common cause of lamb death is brain injury at birth. Dr Gordon Refshauge (Livestock Research Officer with NSW DPI and ewe reproduction specialist), has researched lamb survival and ewe reproduction for many years. In his opinion, most lambs die with injury to the CNS (Central Nervous System). This means even if they were taken by a fox, or were born when it was cold, they were never going to survive anyway.
On 6 August, a lamb autopsy day will be held at the Buraja Football Ground with guest speakers Rob Inglis (ruminant nutritionist and Elders animal health coordinator), and Scott Ison (District Vet with Murray Local Land Services).
On 7 August, another lamb autopsy day will be held at 'Aintree Park' near Howlong with guest speaker, Dr Gordon Refshauge. Hosted by Southern Riverina Sheep Breeders together with Sheep Central, NSW DPI and Murray Local Land Services, there will also be a talk on the NSW drought feed app by Geoff Casburn from DPI.
A lot of landholders are getting very good scanning rates this year, but are at a loss as to why their lamb mortality rates are still high. These workshops will help explain some of the reasons, by focussing on how to do your own quick autopsy to identify the cause of lamb deaths, and how sheep breeders can take action to reduce losses by fine tuning their flock management.
Most studies have shown predation is actually a very low contributor to lamb losses. The next most important question is - can these losses be avoided? Typically, the answer is yes – the level of mortality can be significantly reduced through accurate management of the ewe using condition scoring.
Most lambs that die look like the lambs that live, so unless you know how to look under the surface, it's hard to identify the real causes. Luckily there are some easy ways to identify what's really going on in your flock. Participants are encouraged to bring in their dead lambs (refrigerated, not frozen) no older than 7 days and dead no more than 3 days.
Come along to the workshops by registering with:
Gen Reardon of Murray LLS, for Buraj, p: (02) 6051 2253, m: 0409 077 254
Justin Everitt of Southern Riverina Sheep Breeders, for Howlong, m: 0419 280 105