Producers are asked to watch for signs of lupinosis in sheep grazing lupin stubbles, following recent rains across much of the wheatbelt.
Department of Agriculture and Food veterinary officer Anna Erickson said lupin stubbles had always been favoured as a good source of feed, particularly for weaners in their first summer.
However, Dr Erickson said after rain, lupin stubbles were prone to developing a fungal disease called phomopsis, which is toxic to sheep.
She said even phomopsis resistant strains of lupins could develop the disease if conditions were right.
“Most lupin stubbles will have 150-200 kilograms of lupin seed per hectare left after harvest,” Dr Erickson said.
“Weaners will start to lose weight, and graze the lupin stems when seed levels fall below 50kg/hectare.
“Grazing the stems increases the risk of lupinosis. The fungus develops on lupin stalks first, but pods and seed can be affected if conditions are wet enough.”
Wet lupin stems are softer and more palatable to sheep, increasing the risk of them being eaten.
“Sheep should not be allowed access to lupin stubbles, including fresh stubble, for 7-10 days after rainfall. This gives the stubble a chance to dry out,” she said.
Dr Erickson said all sheep grazing lupin stubble should be monitored closely for developing symptoms of lupinosis, and sheep should be removed from the paddock when seed levels on the ground drop below 50 kg/hectare (about 40 seeds per square metre).
Early signs of lupinosis include hollow flanks, lethargy when driven, noticeably poor growth rate and individuals not keeping up with the mob or staying near water points.
Clinical cases show disorientation, blindness, hunched appearance, reluctance to move and yellowing of the membranes around the eyes and in the mouth.
Sheep should be removed from the paddock and veterinary advice sought at the first sign of suspected lupinosis.
“Farmers should ask their veterinarian to investigate stock suspected of having lupinosis to confirm the diagnosis and enable the exclusion of trade sensitive diseases such as blue tongue virus and Peste des Petits Ruminants (PPR), which do not occur in Australia but share some of the clinical signs,” Dr Erickson said.
“This information is valuable as it helps validate Western Australia’s favourable animal health status, which enables market access for our livestock and livestock products,” she said.
DAFWA has financial subsidies available to producers to encourage disease investigations. This program aims to boost surveillance for early detection of emergency animal diseases and provide evidence of disease freedom for ongoing market access.
More information about lupinosis is available on the DAFWA website.
Media contacts: (available 21 Dec only): Lisa Bertram, media liaison, +61 (0)8 9368 3937