Drench Resistance is the number one animal health issue facing farmers and their vets in the sheep & beef industry.
We are very concerned – here’s why.
- We have no new tools in the box to tackle this issue. No new knowledge, no new drench families, and we have to work with what we currently have.
- Only 15% of our clients actually have up to date knowledge of what their drench status is, yet half of the faecal egg count reduction tests (FECRTs) we do have significant drench resistance results
- You won’t see it coming until the shit hits the fan (or hand piece in this case).
Drench is the silent, slow onset profit killer. It starts out costing you 5grams/day (which you can’t see) and builds up over time. We see farmers become aware they may have a problem during a wet summer/autumn when the worm population on farm is more active and cycling quicker and farmers start knocking on our door with high FECs and poor doing stock.
Economics – What Parasites cost you!
Lost growth of 5grams/day over 2000 lambs for 90 days at $3.50/KgLW = $3,150 (cost of your family summer holiday).
When it gets into the 25grams per day territory the cost = $15,750 (cost to feed 2 teenagers each year!)
What we can do to help
You can farm successfully with drench resistance if we know what we are dealing with and develop a parasite management plan specific to your farming conditions.
Our vets can help get you started by setting up a Faecal Egg Count Reduction Test (FECRT). The purpose of FECRT’s is to compare the change in the number of parasites in your animals FEC before drenching (or with no drenching), with the FEC at 10 days after drenching. The result is reported as the percentage that the egg count has been reduced.
We generally get the best results when we have a wide mix of significant worm species present. In Hawke’s Bay the best time to complete a FECRT is between January and March when Ostertagia, Trichostrongylus, Haemonchus, Chabertia/Oesophogostomum, Cooperia & Nematodirus are most likely to be present.
- When testing drench resistance in Sheep we ideally want to use undrenched lambs so, identify lambs with a tag prior to the mob receiving a drench
- You will need 12-15 lambs for each test group. Pick the lighter lambs, but avoid the real runts.
- Each group will be drenched with one drench so if you wish to test four drenches you will need 50-60 lambs for the test.
- When completing a FECRT in cattle we understand that it’s often not realistic to use undrenched animals.
- Instead, try to select animals that were brought in as calves are are now in the 100-150 kg weight bracket.
- They are often wormy enough 6-7 weeks after an oral drench to begin the test.
- We need 15 animals per drench tested.
- Draft out and identify the test animals (70-80, having more than needed allows some extras at the first set of testing).
- Identify these by spraying with an aerosol raddle (most common method) between shoulders for further identification. Please don’t spray them on the rump as we use that area to identify treatment groups at time of testing. Identify these lambs at the first muster, which will be pre-wean or weaning.
- Do not drench them, even if you do the others. The test results are best when these animals have never received a drench.
- They can remain with their flock mates or run on areas that you expect they will keep being exposed to sheep worms (not a cattle block, for instance).
- At next yarding draft off the marked lambs. Keep them separate from now on.
- Take a FEC sample from the identified FECRT lambs once they start to look a bit shitty – this often takes until late January or well into February but do make sure they have been covered for fly and that you keep an eye on them.
- Take ten individual faecal samples. This is easiest done by paddock collection but ensure you submit fresh faeces. Otherwise collect directly from the rectum with a gloved finger. Wipe your gloved finger very carefully between lambs to avoid cross contamination. We need at least 1 teaspoon of faeces per sample. Fill in the submission form accompanying the samples and identify as PRE-FECRT #1.
- Do not refrigerate these samples but get into the clinic as soon as possible.
- Results will be reported by your vet within 48 hours.
- Once levels are high enough (aiming for an average of 500-700 epg with no zero counts) we will start the FECRT.
When managing parasite populations there are lots of factors to consider. Our vets can talk you through the process and help design a management plan which is unique to your farm.
If you would like to find out more, or book a FECRT please call us on (06) 876 7001 or email .