Sheep farmers can boost productivity and profitability with a pre-lambing checklist
Friday, March 11, 2016
Sheep farmers who lamb from autumn to spring are being reminded that now is the time to review your lambing checklist for the 2016 season.
“Productive sheep need careful management all year round,” says Livestock Technical Veterinarian for Virbac Australia Dr Susan Swaney. “It’s important for two reasons. One, so you can have the best possible lambing, getting the most lambs on the ground with optimal survival and growth rates. And two, so your ewes can recover quickly and be fertile for next year.”
Autumn may have just started, but as we head into the cooler months, proper planning for lambing can help farmers increase productivity and profitability.
Pregnancy scanning 45 days after rams are removed will help you separate ewes based on how many lambs they are carrying, so you can allocate feed and reduce the chance of mismothering. Triplets should be lambed down in flocks no more than 30. Twins should be in flocks of 100 or less for Merinos and 150 for crossbreds, and singles in flocks of 250 or less for Merinos and 300 for crossbreds.
Managing the condition score of ewes is also critical to make sure lambs are born at the ideal weight of 4.5kg to 5.5kg to avoid death due to mismothering, exposure or birth difficulties. Single carrying ewes should be at CS3.0 and multiple carrying ewes at CS3.5-4.0.
“Nutrition is vital too,” says Dr Swaney. “But if you have had poor nutrition in early pregnancy it is important to give good nutrition in the last trimester.”
Some farmers increase the feed quantity for that final trimester by deferring grazing in the first weeks. The ideal food on offer (FOO) during lambing for single carrying ewes is 1200kg DM/ha, and twins and triplets is 1800kg DM/ha. During the peak lactation period this increases to 1500kg DM/ha for single carrying ewes and 2000kg DM/ha for twins and triplets.
In addition, ewes should be going into lambing vaccinated against preventable diseases, topped up with trace minerals and treated for parasites – a treatment trio Dr Swaney describes as “treating for productivity.”
The foetus needs adequate trace minerals to prevent deficiencies, and the ewe also needs them for immunity and post-lambing recovery – as she transfers 30 per cent of her supply to the foetus. Dr Swaney recommends an injection of Multimin, which provides a top-up of zinc, manganese and selenium, to help replace the large drain put on her mineral resources at this time. Vaccines protect both ewe and lamb, especially from clostridial diseases that occur due to the trauma of birth and during the early stages of low immunity for the lamb by bolstering the colostrum. And parasite management is one of the most critical issues facing sheep farmers at this time.
“The ewe is most susceptible to parasites during lambing,” explains Dr Swaney. “During late pregnancy and lactation, there is a large drain on the ewes protein and energy, which results in a lowered immune response allowing worms in their gut to lay more eggs.”
Consequently heavy contamination of pastures can lead to a year long problem where both ewes and young lambs are affected – impacting growth and long-term productivity.
Dr Swaney recommends a pre-lamb drench for ewes, such as Cydectin Long Acting Injection for Sheep – applied with a quick, simple injection.
“This treatment is more potent than an oral dose, and provides longer acting worm control – keeping your pastures cleaner, reducing parasite exposure to lambs and increasing productivity.”
With a long acting treatment, you need to drench less often, which may help prevent the development of worm resistance.
Complete your pre-lambing preparation by planning to crutch instead of shear. Shearing ewes pre-lambing can increase ewe feed requirements by 25-30 per cent, due to the cold. And taking ewes off pasture for shearing can cause them to lose weight. In addition the benefit of shearing to encourage ewes to seek shelter at lambing has been shown to only be effective for two weeks off shears.
“You should also keep up all your regular sheep health monitoring practices,” says Dr Swaney. “Make a checklist and stick to it to maximise the number of lambs, increase survival rates and have a successful lambing.”