Putting Merino weaner management recommendations to the test
J. E. Hocking Edwards A B , R. M. Gould A and K. J. Copping AA South Australia Research and Development Institute, Struan Research Centre, Naracoorte, SA 5271, Australia.
B Corresponding author. Email: Edwards.Janelle@saugov.sa.gov.au
Australian Journal of Experimental Agriculture 48(7) 974-978 https://doi.org/10.1071/EA08003
Submitted: 4 January 2008 Accepted: 16 April 2008 Published: 20 June 2008
Abstract
Merino weaner survival is poor under normal traditional management practices. Data from four trials conducted between 2001 and 2005 were used to assess the effectiveness of current industry recommendations to achieve 95% survival rates of Merino weaners. There was very little difference between 2001 and 2003 in survival of Merino weaners despite average weaning weight ranging from 20 to 24 kg between years. The recommended target weaning weight of 23 kg does not always appear to be a good predictor of survival. However, a target of 45% mature liveweight at pasture senescence achieved the industry recommendation of 95% weaner survival. Merino weaners were fed over the summer–autumn period to reach 40 kg liveweight by the time green feed became available. Weaner survival reached 93% compared with 89% survival to hogget shearing in weaners managed under normal growth paths. Furthermore, twice as many ewe weaners died in the traditional feeding program compared with the well fed ewe weaners. Differences in mortality between feeding levels in the wether weaners was less than that observed in the ewe weaners. Flock average growth rates were not useful indicators of weaner survival and there was no relationship between Merino ram estimated breeding values for weaning weight and the survival of the progeny.
Acknowledgements
This work was supported by the prime lamb industry through Meat and Livestock Australia Ltd, Merino ram breeders, South Australian Stud Merino Breeders Inc., Australian Wool Innovation Ltd and Allflex. Lifetime Wool is a national project, funded by woolgrowers through Australian Wool Innovation Ltd and the state government departments of Victoria, Western Australia, New South Wales, South Australia and Tasmania. Many thanks to Doug and Lachie Stewart for the opportunity to conduct the South Australian Lifetime Wool trial on their property.
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