Given that many flocks went into lambing this year in lower than normal body condition, two things can happen from here:
1. We get good grass growth through the rest of spring/early summer, which we control well with appropriate management, ewes are fed to appetite and wean in Body Condition Score (BCS) 3, pastures are in tidy order and maintain reasonable summer quality, lambs grow well on our better grass and crops, and we're set for next year ...
2. Nature does its usual balancing act and we get poorer than normal Oct/Nov pasture growth, ewes wean in light condition ... or we don't control rapid growth well, are left with poor quality summer feed which ewes can't gain weight on, and is hopeless for growing lambs
And hold on - a unit of BCS in a ewe is about 5-7kg LW; if we body-condition scored these at docking there'd be many around BCS 1.5 - this requires 15kg to be gained on these sheep to wean at BCS 3. If we dock at Labour weekend and wean just after New Year, this is a growth rate of 215g/day.
Are we managing our ewes to achieve this? And we don't achieve it, what plan do we have in place to ensure those thin ewes do gain that weight over the summer? And do we know (objectively) who those ewes are? And how many? The answer to the last question will put some limits around what can be practically achieved if it is a large proportion of the flock.
So what can we do between now and Christmas to help get the ewes back on track and maximise the growth performance of the lambs? A lot will depend on how the feed situation pans out and how we manage that. But some ideas for consideration are:
At docking
- Tag and weigh some first cycle lambs - an average growth rate for lambs on mum on hill country between docking and weaning is 180 - 190g/day, you can work out what they'll be at weaning, or look for strategies that will make them grow better than average.
- Drench light ewes - likely to be worth the effort given the high worm challenges that persisted through the winter. Go for a short-acting, highly effective combination drench.
After docking
- Start a rotation, especially if feed is looking like getting away, drop out paddocks that can be controlled in other ways.
- Once a rotation is underway, creep grazing of the lambs is an option, where there is reasonable subdivision (paddocks less than 16ha/40 acres). Straight bar gates with every 2nd bar sawn out can be moved from paddock to paddock for this job, to allow the lambs to get a fresh pick ahead of the ewes.
- Get your summer brassica crops in early, even if sowing method has to be a compromise. This ensures lamb feed comes on stream at the right time and reduces the temptation to keep grazing these in late summer when you know jolly well the new grass should be getting sown!
- Chat to your vet about the pros and cons of a pre-weaning drench of lambs. Where ewe condition and low feed have compromised milk production and persistence, this may help. Not necessary in all situations but something to bear in mind.
At weaning
- Indentify, drench and look for strategies to improve light ewes.
- Ewes that were given a long acting (100+ days) worm treatment pre-lamb need an ‘exit drench' by now if not done already. Talk to your vet about this.
