ON FARM SHEEP ANIMAL HEALTHZ Reversing resistanceJen and Darren Smith,SNAPSHOT: J en and Darren Smith had beendealing with drench resistance intheir Merino flock for some time“Then the ewes get their second dosefor the season at lamb marking when thelambs get their first. All the sheep then getKentucky, NSWS when they first tried Barbervax®. vaccinated every six weeks until about April, when the danger period for barber’s pole “Barbervax vaccine was a godsend for worm infestation ends.” managing barber’s pole worm,” Jen said. Jen (pictured) said that because Barbervax “The two newest drench products on the has no withholding period or export slaughter market – Startect® and Zolvix™ – were interval, it improved market flexibility. working for us, and continue to do so, but the other drench classes were not. “Although we’ve had a couple of dry summers, I remain confident we’ll get a good result Area: “We weren’t losing sheep, but they were from the Barbervax,” she said. 700ha taking a lot of work to manage. We were drenching up to eight times a year.” “The one challenge we have with it is in Enterprise: relation to our ram breeding nucleus. There’s Merino sheep In the first year of using Barbervax, the Smiths (who both have full‑time off‑farm an antagonism in that you can’t collect Livestock: jobs) used it with young sheep only. The worm egg counts for Australian Sheep A 1600‑head self‑replacing following year, they used it more broadly Breeding Values from sheep that have been ewe flock with one‑third and now every sheep on the property immunised with Barbervax. joined to White Suffolks and is vaccinated. “We’d like to be working better to improve the remainder to Merinos “We follow the rules closely for giving the genetic resistance to worms but also want to Pasture: Barbervax,” Jen said. use Barbervax. At the moment we’re limited Predominantly native in what we can do in that area because we pastures with some forage “Starting at marking, the lambs get three can’t do the two things at once.” ■ vaccinations in close succession to prime crops for lambs their immune systems. The ewes get their Jen Smith Soil: first vaccination for the season in September, T: 0411 825 748 Light granite soils just before they start lambing. Rainfall: 700mm 2266