LIVESTOCK | MANAGEMENT
Weaning for a successful tupping BY: BEN ALLOTT
O
n a breeding farm, weaning is the culmination of all your efforts through the year. Watching healthy well-grown lambs leave your farm and watching the next generation of replacements start their productive lives is your reward for all the work put into the past year. It is also critically important to appreciate that your decisions made leading into weaning and the decisions you are about to make on managing ewes through the summer have a huge bearing on how successful you will feel this time next year. Ewe condition is the top priority. At this stage of the year it is easy to focus on the short term goal of maximising lamb weaning weights and under appreciate the impact this focus can have on ewe BCS
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and mating performance next autumn. Some key points to seriously consider and talk to your neighbours and advisors about: • By day 70-80 of lactation, ewes on good feed are only producing 30-40% of the milk yield they were at peak lactation. Ewes losing condition on tight allocations, or poor-quality feed, are producing even less. Lambs are now getting the majority of their energy for growth from pasture. In many cases, lambs will grow just as well and probably better if weaned early on to high-quality legume, herb, or brassicadominant feed. • Summer is a hard season to put weight back on ewes and you only have 90 days until tupping. In most pasturebased systems you are doing well if you can feed ewes to gain 50g/day. Over the 90 days between weaning and tupping this equates to just 4.5kg liveweight (roughly half a BCS). If you are a summer
dry East-Coast farm with regular summer dry challenges, or a wetter North Island property with facial eczema, and higher parasite challenges through summer, then in many seasons this degree of summer weight gain is a real challenge. You cannot afford to see ewes losing condition leading into weaning in an attempt to drive lamb performance. You will struggle to gain this lost weight back in time for the ram. • Ewes losing weight is inefficient - each kg of ewe liveweight loss releases 17MJ of energy to go into milk. It then takes 65MJ of energy above maintenance to regain each kg back through the summer. It doesn’t make sense to rob condition from your primary productive unit when the conversion to product is inefficient. If feed is abundant, and quality is good leading into weaning, the pressure to make timely decisions is reduced. But if ewes and lambs are competing for quality feed, if lambs on mum are hardening off, if ewes
Country-Wide
December 2020
