Wormwise manager Dr Ginny Dodunski. PHOTO: BEEF+LAMB NZ

Farmers are being told to step up their ewe performance for lambing after a ban on Bionic Capsules for treating and controlling internal parasites.

Sheep veterinarian and Wormwise manager Dr Ginny Dodunski said farmers who had stocked up on bionics would be disappointed.

"Farmers need to be aware that they cannot use these capsules even if they have already purchased them."

The Beef + Lamb NZ-funded Wormwise programme had earlier flagged the unavailability of bionics as both a threat and an opportunity to farmers who traditionally relied on them to support ewe performance over lambing.

The Ministry for Primary Industries has now issued an alert banning their sale and use.

"To farm successfully when these products are withdrawn from a system involves a strong focus on improving ewe body condition and setting up the farm to feed ewes properly coming into lambing and early lactation," Dr Dodunski said.

She said choosing sheep genetics which could better deal with worm challenges could also play a part.

Farmers should consider body condition scoring their ewes when the ram is removed and again at scanning.

Ewes that start the winter with a body condition score of less than 2.5 are twice as likely as their better conditioned flock mates to be culled, dead or missing by weaning. They should be identified, drafted out and a plan made to look after or quit them.

Farmers are being advised to work out their daily feed demand for the next three months. Typically it will be lower than the daily pasture growth rate.

That will help them gauge their position at lambing and the actions they need to take so there is enough grass for ewes in the critical few weeks before lambing and into early lactation.

Dr Dodunski said there were other long-acting products available if the gap "between actual and ideal" was going to be too wide this year.

"Get advice from an experienced sheep veterinarian on the best way forward to carefully use these on the most vulnerable proportion of the flock and then put some dates in the calendar to review how this went. Most importantly, make a more sustainable plan for lambing in 2024."

Farmers wanting training in feed planning, body condition management and sustainable drench use are encouraged to contact their B+LNZ extension manager for workshops.