Cattle Drench Resistance: how to avoid resistance with drenches in cattle

Cattle Muster - Drench Resistance

Drench resistance. Two words likely to give any cattle producer a headache. The problem is well known: just as quickly as you can drench your cattle, the gastrointestinal roundworms build up a chemical resistance against the drenching treatment. We often have producers call up who are experiencing this exact problem, seeking advice from our team on the all-important question: “How can I avoid resistance with pour-on drenches in cattle?” 

What causes drench resistance?

For the Australian beef and dairy producer, resistance to the macrocyclic lactone (ML) group of anthelmintics is a serious problem. When the MLs were first introduced in the late 1980s, resistance was widespread to the older drenches. The new drench type was a much-needed lifeline, rapidly transforming worm control in cattle. Unfortunately, the parasites fought back very quickly. 

Drench resistance is a genetic trait caused by internal parasites inheriting drench resistance genes, allowing for tolerance to commonly-used drenches. The actual resistance arises as a result of random mutations in worm genes. These mutations are initially rare, but as we all know, all it takes is for a tiny percentage of worms to develop resistance and the resistance cycle kick starts. 

One tiny parasite with a gene mutation passes on this resistance mutation to its offspring. The offspring do the same, and before you know it the overall parasite population with resistance to treatment has increased to the point of no return, rendering the drench almost ineffective.


What are the differences between worm resistance and drench resistance?

In simple terms, worm resistance is the livestock’s resistance to worms, whereas drench resistance is the actual worm developing or inheriting resistance to a particular drench. It is important to note that parasites can be resistant to multiple types of drenches, hence why drench rotation is so important.


How often should I drench?

The question of how often should I drench is really broad, with the answer really depending on circumstances such as which parasite you are treating, where your livestock are located in Australia, and what weather the area has been having. Drench frequency also depends on the age group or management period of the animal. In cattle for example (per the NSW Department of Industries guide), drenching varies depending on whether we are talking about weaners, yearlings, bulls etc. 

At Specialist Sales, we’ve been in the industry for many years, and there’s not much we haven’t seen. We are experts in the drench needs of producers, which is why so many producers turn to us when it comes to seeking advice and guidance on anything drench related, especially drench resistance. Talk to our friendly team for further information pertaining to your specific situation.


How long does a drench last? 

The length of drench efficacy depends on the type of drench used, as well as several environmental factors. The more potent the drench the longer they last, and the less frequently drenching needs to occur. Weather, in particular rain and drought, also affect how long the drench will last. We can help you to get the most out of your drench; similar to the question on how often you should drench, a brief chat with our knowledgeable team can answer your drench related questions and help you get more longevity out of your drenching.


How do I avoid drench resistance?

The key to avoiding drench resistance is to develop and implement a sustainable rotation plan. Changing the active ingredient of the drench used on a regular basis helps to avoid build-up and parasite resistance, as does the correct and early identification of parasite resistance.

Combined, these are vital to maintaining herd health. To avoid resistance, an effective management program must be undertaken incorporating a number of steps: 

  • Choosing the right chemical active for your needs and planning the rotation of these activities. Producers cannot keep using the same macrocyclic lactone (ML or ‘mectin’) drenches repeatedly otherwise parasites build up resistance to these products. It is critical that rotation is based on the active ingredient, not a brand name! 
  • Planning the timing of the treatment. 
  • Knowing your animal and possible triggers of contamination. 
  • Knowing your market, such as when you need to sell or move cattle.

What are the best drench products to use?

With so many cattle drench products on the market nowadays, it can be difficult for farmers to know which product is the right one for them. For us here at Specialist Sales, cattle drench is one of our most popular product categories.

When it comes to selecting a drench, you’ve got three options:

  1. Pour-ons
  2. Injectables
  3. Oral administered

Pour-on Drenches

Pour-ons are vital to the health and quality of livestock. These easy to administer products safeguard cattle from a vast range of parasites that can quickly impact the health of entire herds. Ultimately, when it comes to finding the right pour-on for your needs, you want to ensure that you’re getting the most bang for your buck. 

A broad spectrum cattle pour-on that protects your livestock from a variety of parasites, for an extended period, will save you time and money. The list below outlines the most convenient and affordable pour-on solutions for Australian producers. These are our top-selling cattle pour-ons, and outline how they could enhance parasite prevention and extermination throughout your property.

Cydectin Cattle Pour-On

Cydectin is a very potent and persistent pour-on for parasite control among cattle. It protects your herd from both internal and external parasites such as roundworm, barber’s pole worm, several species of stomach and intestinal worms, lungworm, cattle tick (controls for up to 21 days), lice, mites and more. Cydectin will also aid the control of buffalo fly for up to 14 days after treatment. This hardy pour-on is both weatherproof and rainfast, proven to be effective despite shifts in temperature and moderate rainfall. Parasites have less resistance against Cydectin than other macrocyclic lactones (ML), meaning that infection can be prevented altogether.

Furthermore, the active in Cydectin drenches is dung beetle friendly.  The dung beetle breaks down the cowpat and buries it into holes they dig. By burying dung in the soil, beetles improve the flow of water, nutrients and carbon into the root zones of pastures, which in turn: boosts pasture productivity (dung beetles can increase the pasture growth response by ~30% over a two-year period).

Most conveniently, the pour-on’s long-lasting effects reduce the frequency of treatment, freeing up more time for you to complete other tasks. Production can also be expedited due to zero meat and milk withholding periods.

Choose from our range which includes Maximo.

Ivomec Cattle Pour-On

Ivomec also safeguards cattle from a variety of internal and external parasites including, but not limited to, gastrointestinal roundworms, lungworm, eyeworm, biting and sucking lice, mites, buffalo fly and cattle tick. Ivomec pour-on has been known to control lice in cattle for up to 56 days! It targets parasites in both adult and immature stages of development. It is important to note, Ivomec, and equivalent products can differ in their withholding periods. For example, while Ivomec should not be applied to cattle less than 42 days before sending to the abattoir, other products such as CattlePro, has a 28 day meat WHP  and nil milk WHP.

We have been selling our own brand of affordable Ivermectin Pour-On Drench CattlePro to cattle producers Australia wide for a number of years now. Such a large quantity has been shipped through our warehouse that we can now say it is our highest selling drench!

CattlePro comes in a variety of sizes to cater for all producers, large and small. Sold individually or as a packaged deal, it has now been used by customers for over four years with excellent results.

Levamisole Pour-on

SureShot Gold is a new levamisole based pour-on drench for cattle, and is a terrific alternative to the ‘mectin’ drenches commonly used to treat internal and external parasites.Please note that Sureshot does not treat any external parasites.  Levamisole is a key active ingredient used in the fight against drench resistance.

SureShot Gold Pour-On Cattle Wormer controls all major gastrointestinal roundworms in cattle. Unlike all other pour-on products containing levamisole, SureShot Gold has 25% more active ingredients per dose and offers a nil-milk withholding period, making it the ideal drench rotation solution for beef (3 day meat WHP) and dairy farmers (Nil Milk WHP). 

Sureshot Gold Cattle Wormer is manufactured in Australia to the highest quality standards and is a product well trusted for its efficacy. It is sold through Specialist Sales and is available in either 5L or 20L pack sizes.

Coopers Paramax Pour-on

Coopers Paramax Pour-on is used for the treatment and control of Ivermectin-sensitive gastrointestinal roundworms, lungworm, eye worm, sucking & biting lice, mange mites, buffalo fly and cattle tick in cattle. This product is widely used in rotation to avoid drench resistance.


Injectable Drenches

Injectable drenches are another popular treatment and control method of a variety of cattle parasites. Some of our most popular injectable drenches are listed below.

Dectomax Injectable

Dectomax Injectable is indicated for the treatment and control of gastrointestinal roundworms, lungworms, sucking lice, biting lice, cattle tick and mange mites. This product comes in several pack sizes, and is widely used in rotation to avoid resistance.


Doramate Injectable Endectocide is ideal for the treatment and control of doramectin sensitive internal and external parasites of cattle. One dose of Doramate injectable solution effectively treats and controls a wide range of roundworm and arthropod parasites that impair the health and productivity of cattle. Studies have demonstrated the safety margin of Dectomax injection in cattle.

Cydectin Injectable

Cydectin Injectable for cattle  is effective against moxidectin sensitive gastrointestinal roundworms (including inhibited larvae of Ostertagia ostertagi), lungworm, sucking lice and mange. Further, it is effective for control of cattle tick (Rhipicephalus (Boophilus) microplus) including strains resistant to organophosphates, synthetic pyrethroids and amidines.


Bomectin Injection is an Ivermectin containing, ready-to-use broad spectrum antiparasitic injection for cattle. Bomectin Injection will treat and control internal parasites including gastrointestinal roundworms, lungworms, eyeworms, sucking and biting lice, mites and cattle tick.


Oral Drenches

Specialist Sales also stock a wide range of oral drench products, the most popular of which are listed below. 

Nilverm LV Oral Drench

Nilverm LV (Low Volume) Oral Drench is a broad spectrum drench for the control of susceptible roundworms including lungworm in cattle and mature Ostertagia spp in cattle under 12 months of age. Nilverm LV Oral Drench contains levamisole, a member of the imidazothiazole (clear) group of anthelmintics (drenches) and is effective in cattle against a broad range of pathogens. 

Fenbender 100 Oral and Panacur 100

These two products, Fenbender 100 Oral Anthelmintic and Panacur 100 Oral Anthelmintic for cattle, are ready to use broad spectrum worm drenches for the control of benzimidazole sensitive mature and immature roundworms and lungworms.

Trifecta Triple Action Drench

Trifecta Triple Active Drench for cattle is a triple drench that defends cattle against drench resistance.  Trifecta contains 3 different active ingredients to kill worms. Even if a worm population is resistant to one active it will be killed by the others. As a result triple combination drenches are recognised as a very effective tool in long term drench strategies.

Worma Oral Drench

Worma Oral Drench for cattle made from Oxfendazole provides an economic and convenient method of controlling roundworms and tapeworms in cattle on studs, dairy herds, feedlots and grazing stock.


Do you have any drench questions including drench resistance?

We have years of industry knowledge and experience to offer valuable advice to our customers when they’re unsure about which cattle drench is best suited to their needs. Contact our knowledgeable, friendly team for advice on cattle drenching.

At Specialist Sales, we are firm believers that if we can’t save you money, we don’t deserve your business. View our range of Animal Health products to see our pricing for yourself.

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