Worms are growing increasingly resistant to parasites

Article by Zoetis Australia

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Worms are growing increasing resistant to parasites. Infected cattle have 7.4% less average daily weight gain¹⁷ and can have 5.4% lower feed intake¹⁷.

Dr Matthew Petersen, Livestock Operations Manager at Zoetis recommends that reseller staff ask their producers six questions before selling a cattle drench:

• Is the drench being used for weaners and young, growing cattle?
• Are they buying cattle in or bringing cattle back from agistment blocks?
• Are cattle being inducted into a backgrounding or feedlot facility?
• Have they been disappointed by previous results from drenching?
• Have they had parasite resistance diagnosed on your farm?
• Do they also need to control ticks and/or lice?

If a producer answered ‘Yes’ to any of these questions, the producer should consider using a dual active drench to ensure a high efficacy worm kill and to either prevent parasite resistance developing on your farm or break existing resistance profiles, said Dr Petersen.

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Introducing Dectomax V – Australia’s first injectable dual active drench

DECTOMAX V is ideal for all weaners and young, growing cattle which are most economically impacted by worms. Given its very high treatment efficacy, Dectomax V is ideal as a quarantine/induction drench to prevent resistance worms entering a farm with brought in stock. It can also be used in replacement breeding stock, such as replacement heifers and where necessary can be used in adult cattle. It is an ideal product for use on entry to backgrounding and at induction prior to feedlot entry to ensure resistant worms don’t hinder weight gain.

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DECTOMAX V is an evolution from Dectomax which has been trusted and used across Australia for over 20 years. DECTOMAX V combines the trusted performance of doramectin, from Dectomax, with the added strength of levamisole. DECTOMAX V is the first injectable ML/Levamisole combination product registered in Australia and provides a dual active killing power with unsurpassed efficacy against key parasites, including those often resistant to other single active drenches.^1-14

Providing high efficacy, this broad spectrum parasiticide with new dual active technology is designed to kill the most damaging parasites, including resistant worms. Easy injectable administration results in highly reliable dosing. In addition to treating gastrointestinal worms, it also controls cattle tick & sucking lice.

THE PRODUCT CLAIMS

• For the treatment and control of adult and L4 larval (immature) stages of gastrointestinal worms, including both macrocyclic lactone and levamisole resistant strains
• For the treatment and control of Cattle tick – prevents development of viable ticks for 30 days after treatment
• For the treatment and control of Sucking lice – 56 days
• Safe for use in calves from 3 months of age and at all stages of pregnancy
• MEAT WHP & ESI: 35 days

Refer to product label for registered label claims.

WHEN DEALING WITH RESISTANT PARASITES, DELIVERING THE RIGHT DOSE IS VITAL.

An injectable drench is deposited below the skin and absorbed directly into the bloodstream. Injectable drenches therefore achieve higher peak blood and tissue levels compared to pour-ons. Injectable drenches slow the development of resistance.¹⁶ Doramectin when injected achieves higher tissue concentrations than ivermectin and moxidectin.

 Dectomax V was also compared to leading drenches in Australia and the results were outstanding with an overall mean efficacy of 99.8% across 13 studies¹⁸. However, two leading single active ML drenches used for comparison both showed results less than 95%, indicating a growing level of resistance to this drench class.

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FORMULATION AND PACKAGING

Dectomax V is packaged in a 500 mL amber glass bottle in a recyclable protective sleeve. It will also be available in a Victory pack, which includes 6×500 mL bottles and a metal injector. As with all ML-Levamisole products, it needs to be stored below 25 °C (air-conditioning).

DECTOMAX V is safe to use from 3 months of age and at all stages of pregnancy. DECTOMAX V has a 45-days broaching claim when stored according to label.

References:

1.Zoetis Inc. DECTOMAX V Australian Product Information. 2021. 2-14: Zoetis Studies: A3580, A3595, A3596, A3798, A3881, A3809, A3858, A3861, A3862, A3863, A3864, A3860, A3859. Data on file. 16. Leathwick (2021) Vet Parasitol 17. Stromberg, B. E., et al. (2012). “Cooperia punctata: effect on cattle productivity?” Vet Parasitol 183 (3-4): 284-291. 18. Overall mean efficacy (GM) of 99.8% across thirteen field studies. Zoetis data on file.
Written by Dr Matthew Petersen BVetBiol, BVSc is a Livestock Veterinary Operations Manager – Zoetis Australia Pty Ltd.