In response to the anticipated dry conditions along the east coast of New Zealand’s islands, agricultural experts are advocating for the early weaning of a portion of the lamb crop.
This strategy is aimed at efficiently allocating high-quality feed to lambs, thereby facilitating the recovery of ewes’ body condition.
Additionally, it opens up the possibility of selling cull ewes sooner than usual.
Research conducted at Massey University has played a pivotal role in understanding the dynamics of early weaning.
The studies indicate that lambs weighing over 20kg live weight (LW) are most suited for early weaning, with the minimum weaning weight set at 16kg LW.
Crucially, the success of post-weaning growth in lambs hinges on the quality of forages.
Professor Paul Kenyon, who spearheaded these early-weaning trials, emphasises
the importance of providing early-weaned lambs with unrestricted access to legume-based forages, such as a mix of herbs and clover, maintaining a minimum height of seven centimetres.
He also advises a gradual transition for lambs weaned onto crops, suggesting that ewes and lambs be introduced to the crop a few days prior to weaning. This approach helps in reducing the stress associated with weaning.
The practice of early weaning is particularly beneficial in the case of multiple births, where lambs receive minimal nutrition from their mothers during late lactation. Under limited grass growth conditions, competition for feed between ewes and their lambs can adversely affect growth and health.
Therefore, early weaning becomes a critical tool in effectively managing this competition.
Moreover, early weaning proves advantageous for hoggets, as it allows them more time to regain body condition between lambing and subsequent mating cycles. By prioritising
high-quality feed for lambs during the late spring and early summer, the overall farm system benefits significantly.
This approach not only enables the sale of more lambs before the peak of summer but also ensures that ewe lambs reach heavier weights earlier.
Consequently, this creates flexibility in managing feed resources during times when they are more scarce, benefiting the entire flock.
