An investigation of micronutrient supplementation in weaner lambs to improve growth rates in south east Australia

Research output: Contribution to journalArticle


A producer survey by questionnaire assessed what supplements are used in sheep and the reasons. This was followed by field trials on eight sheep properties in SE NSW to determine the effect of commonly used commercially available supplements on growth rates of Merino and crossbred lambs.

On each property, 450 lambs were selected at weaning and randomly allocated to 9 groups of 50 sheep (eight treatment and a control group). Supplements were applied as per manufacturer’s recommendation every 6-12 weeks. At each application all sheep were weighed and data on general flock health and management was collected.

All but one of the survey respondents (n=77) had used supplements in their sheep at some stage. The reasons for use were most commonly for general health and production benefits (n=21; 26.9 %) and to prevent or treat specific diseases/deficiencies (n=7; 9.0%)

The average daily weight gains (ADWG) of the lambs over the trial period varied from 0.074kg to 0.213kg/head/day. Statistical analysis showed that overall there was not a significant difference (p=0.587) between ADWG among lambs that received supplements and lambs that did not.

Results of this study show that application of supplements were not linked to improved growth rates in clinically normal crossbred and Merino lambs under the trial farm conditions between weaning and 15 months of age. Effects of supplements on health and production in adult sheep and how supplement response can be best measured in sheep flocks (especially in relation to health and welfare) and linked to productivity requires further investigation.
Original languageEnglish
JournalAustralian Veterinary Journal
Publication statusAccepted/In press - 25 Apr 2020


Cite this