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Tasmania worms, flies and lice update - August 2019

Tasmania WormBoss Worm Control Programs

Tasmania WormBoss Drench Decision Guides

Sheep

Goats

Sheep

Goats


Perth: Paul Nilon, Nilon Farm Health (pandonilon@bigpond.com)

The north has dried out a bit in the last month, but it does not take more than a dense fog to make puddles. The Fingal Valley, east coast, and Bothwell/Derwent Valley are stubbornly dry.

The downside of writing this column is that few things change year to year. By now there are no finishing lambs, Merino weaners are struggling, and ewes are in the labour ward. It’s pleasing the number of clients (and others) who have contacted me regarding the choice of a pre-lamb drench. For those still wondering what drench to use (short-acting (SA) versus long-acting (LA)), the secret is in the egg counts during the autumn and early winter as a meter of overall contamination. Worm Egg Counts (WECs) before lambing are useful if they are high, but play second fiddle to history if they are low. The moral is to record WECs against paddocks all through the autumn and winter, and then a good choice can be made.

There seems to be renewed interest in a drench at lamb marking. There are 3 indications for this: Firstly, it can be used as a salvage (tactical) drench when ewes are parasitised, not milking and endangering the lambs. This situation may occur in the droughted parts of the state. Secondly, if you want to move ewes and lambs to squeaky clean parts of the place such as onto a new pasture or crop. Thirdly, if you are in the drier parts of the state (Tunbridge, Derwent Valley) marking is a good time for the first summer drench. Not many places fit the bill. So, for most punters, a lamb marking drench is not necessary

Finally, for the producers who used long-acting products, it’s important to monitor for drench efficacy. A WEC at 30 and 60 days, plus a larval differentiation (if there are sufficient eggs) will keep track of how your product is performing. If you find eggs, give a tail-cutter (exit drench) drench as soon as possible.