Farm Table says:
What is the problem?
Lamb growth rates following weaning are typically below desirable levels in both Merino and cross bred flocks and are directly influence lamb turnoff dates and have been linked to increased weaner mortality rates. The target of this trial was to evaluate the impact yard weaning has on post weaning performance (growth rates) and its potential to improve the profitability of sheep breeding enterprises. Specifically the intention was:
- understand if an increase in live weight of >2.5 kg/head, 30 days post weaning could be achieved in yard weaned lambs compared to the control group.
- benefit cost analysis of yard weaning compared to conventional weaning practices.
- understand differences in animal behaviour when handling/yarding between the yard weaned and conventional weaned lambs.
What did the research involve?
- Properties chosen for the demonstrations represented both prime lambs and merino enterprises.
- During October/November/December: Imprint grain feeding to ‘trial ewe mobs’ (50-100 g/ewe x minimum of 6 feeds prior to weaning) was carried out by producer trial hosts prior to weaning date.
- Three to four weeks prior to weaning: One ewe mob of at least 250 ewes was chosen from each property as the source of lambs for the trial.
- Weights recorded from 50 lambs selected from the central third of the mob as run through a race.
- Day of weaning: Lambs from ‘trial mob’ ewes were randomly drafted into ‘yard weaned’ and ‘control’ groups to give a minimum of 100 per treatment.
- Yard Weaning: Immediately following weaning the yard weaned lambs were confined to the yards for four days.
- The ration fed to yard weaned lambs was representative of supplementary feed held on each property and not a prescribed specialist ration.
- ‘Control’ and ‘Yard Weaned’ lambs were individually weighed approximately 14 days post lamb weaning date and again at approximately 30 days post lamb weaning date.
What were the key findings?
- Rokewood Victoria: There was a significant difference in weight gain between the treatments in the first 15 days post weaning.
- “Quieter lambs to handle that don’t spook easily. Lambs also flow better through handling facilities. Lambs more likely to stay in their allocated paddocks following weaning when fencing is marginal.”
- Waubra Victoria: weaned composite lambs. There was a significant difference in weight gain between the treatments in the first 18 days post weaning.
- “Saved the weaned lambs from walking off condition for days looking to find their mothers.”
- Shelford Victoria: weaned merino lambs. These lambs achieved an average weight gain of 0.59kg in the first 22 days post weaning or 27g per day. The lambs achieved a weight gain of 1.54kg or 110g per day in the period from day 22 to day 36 post weaning.
- “Calmer. We had a low number of deaths (~2 in ~500 lambs) in comparison to prior years. Quick feed uptake by lambs, less worrying for the farmer.”
- Irrewarra Victoria: weaned composite lambs.There was a significant difference in weight gain between the treatments in the first 35 days post weaning.
- “The lambs break their bond with the ewe and settle down together very well. “