Publication Date
1989
Description
White muscle disease was first reported in grazing livestock in Western Australia by Gardiner (1961). Sheep affected by the disease could be divided into two categories : young suckling lambs in winter and early spring, and weaners and hoggets in summer (Gardiner et al., 1962). Subsequent investigations showed that, while there were few clinical symptoms of selenium deficiency, there were probably many sheep suffering from ill-thrift. This sub-clinical deficiency caused reduced liveweight gains, reduced wool production and lowered ewe fertility. It was most noticeable in areas of greater than 600 mm of annual rainfall on the lighter sandy soils with pasture selenium concentrations of less than 50 µg/kg dry matter (Gardiner and Gorman, 1963). Selenium deficiency may be treated by selenium injections, drenches or intraruminal pellets. The disadvantages of intraruminal selenium pellets are : the lamb has to be at least 12 weeks old before treatment because of the size of the pellet relative to the oesophagus ; they can be regurgitated especially by crossbred sheep ; and the length of time they are effective is variable. Recent work in New Zealand (Millar and Meads, 1987) and Australia (Halpin et al., 1985) has shown that applying the proprietary selenium fertilizer Selcote ® to the pasture is a suitable alternative method. Selcote is a pelleted form of selenate that is diluted with a filler allowing direct application to the pasture. The aim of this work was to compare the suitability of Selcote and a slow-release form of Selcote with the intrarurninal selenium pellet in a mediterranean environment with the desiccated and senescent pasture over the hot, dry summers.
Citation
Whelan, B R.; Peter, D W.; Barrow, N J.; Buscall, D J.; and Cox, V C., "The Effect of Selenium Fertilizer on the Selenium Status of Sheep Grazing Annual Pasture in South-Western Australia" (2025). IGC Proceedings (1989-2023). 3.
https://uknowledge.uky.edu/igc/1989/session7/3
Included in
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The Effect of Selenium Fertilizer on the Selenium Status of Sheep Grazing Annual Pasture in South-Western Australia
White muscle disease was first reported in grazing livestock in Western Australia by Gardiner (1961). Sheep affected by the disease could be divided into two categories : young suckling lambs in winter and early spring, and weaners and hoggets in summer (Gardiner et al., 1962). Subsequent investigations showed that, while there were few clinical symptoms of selenium deficiency, there were probably many sheep suffering from ill-thrift. This sub-clinical deficiency caused reduced liveweight gains, reduced wool production and lowered ewe fertility. It was most noticeable in areas of greater than 600 mm of annual rainfall on the lighter sandy soils with pasture selenium concentrations of less than 50 µg/kg dry matter (Gardiner and Gorman, 1963). Selenium deficiency may be treated by selenium injections, drenches or intraruminal pellets. The disadvantages of intraruminal selenium pellets are : the lamb has to be at least 12 weeks old before treatment because of the size of the pellet relative to the oesophagus ; they can be regurgitated especially by crossbred sheep ; and the length of time they are effective is variable. Recent work in New Zealand (Millar and Meads, 1987) and Australia (Halpin et al., 1985) has shown that applying the proprietary selenium fertilizer Selcote ® to the pasture is a suitable alternative method. Selcote is a pelleted form of selenate that is diluted with a filler allowing direct application to the pasture. The aim of this work was to compare the suitability of Selcote and a slow-release form of Selcote with the intrarurninal selenium pellet in a mediterranean environment with the desiccated and senescent pasture over the hot, dry summers.
