The Complete Guide to Cattle Drenching

Everything You Need to Know to Maintain a Healthy Herd

 No matter the size of your herd, parasite control is a fundamental part of cattle herd management. Cattle drenching is at the heart of this. 

This guide will take you through everything you need to know about cattle drench, one of your most important tools for maintaining a healthy, parasite-free herd. While there is now a wide range of drenches available for internal and external parasite control for cattle, they should always be seen as part of a wider herd management strategy, including pasture and paddock management, in order to keep your herd as healthy as possible.


Why Drench Cattle?

We all know the dangers of internal and external parasites affecting cattle. Every region in Australia has a mixture of parasites that can impact the health and well-being of cattle and mixed infections are not uncommon.

Poor parasite control leads to lower levels of immunity within the herd, which in turn will leave them more susceptible to a wider range of diseases. Lack of proper protection for your cattle’s health can lead to wide-ranging impacts across the herd, such as weight loss, deterioration in hide conditions, lower milk productivity, reduced fertility and symptoms from diarrhoea to weight loss and lethargy. 

This wide range of symptoms is why cattle drenching is so important to control parasites and maintain that all-important animal health, ensuring the productivity and economic well-being that your farm requires.

pour-on cattle drenching

Internal Parasites in Cattle (Worms)

Worm infestations can occur across Australia, in both tropical and temperate regions. The presence of these parasite loads may not always be obvious, meaning that attention and a proper drenching system are necessary throughout the lifespan of your animals. 

Even when the symptoms are not immediately clear, worm infestations can lead to a lack of appetite, generally poor animal health and diminished productivity. Common internal parasites like gastrointestinal nematodes, liver flukes, stomach flukes and lungworms can hold back weight gain and extend turn-off times.

In low rainfall areas, the drenching of cattle of any age for internal worms is rarely required. However, for most areas, once-a-year treatment prior to joining for bulls and prior to weaning for calves is recommended. In fluke-susceptible areas, treatment will be required one or more times a year, depending on the season and severity of the outbreak.

External Parasites (Cattle Ticks, Lice and Mites)

External parasites like lice, mites and cattle ticks must be treated to avoid low growth rates, stressed cattle and hide damage, as well as a wider range of animal welfare implications. Alongside these internal health ramifications, cattle suffering from these kinds of sucking, biting parasites endure constant irritation, leading to a lack of weight gain. 

There are many different lice treatments available for producers that live in lice-prone areas. Treatment of lice usually occurs when treating cattle for internal worms between March and May each year. 

It is most effective prior to the peak season, with all cattle treated over a 7–10-day period. The best time for this is between late summer and early autumn. If your herd only needs treatment for lice, there are lice-specific treatments that can be used.

Tick infestation usually occurs in the northern regions of Australia, throughout late spring and through the summer to early autumn. There are a number of ways to treat cattle ticks, including dips, sprays, pour-on drenches and ear tags. 

Some chemical treatments have an instant ‘knockdown’ effect, while others get into the bloodstream of the cattle and provide up to three months of protection.. Tick resistance is becoming an increasing problem for the cattle industry, making a well-regulated management strategy, built around precise and appropriate dosages and timings, important to ensure not just the long-term health of your herd, but of Australia’s wider cattle population.


What Are the Different Kinds of Cattle Drench?

There are three forms of cattle drench, each with its qualities and drawbacks, and the right drench for you depends on your specific situation. 

  • Pour-on Cattle Drench – This is applied to the backline of cattle and is the most common way to treat cattle for parasites. The speed and ease of application mean that it is possible to treat large numbers of cattle at speed. 
  • Oral Cattle Drench – This form of treatment involves the administration of a pre-calibrated amount of drench into the mouth and throat of the beast.
  • Injectable Cattle Drench – These drenches are administered using an injection to the neck or shoulder area. 


How to Apply Cattle Drench

The actual methodology of cattle drenching of course depends on which of these three methods you are using. Here is a detailed breakdown of each of your three options. 


This is the most common way to treat cattle for parasites. Pour-on drench is applied to the backline of cattle evenly from the withers to the rump via a pour-on applicator and backpack. 

The chemical is absorbed through the skin and enters the bloodstream. The parasites then absorb this blood, giving a wide-ranging efficiency that eradicates the problem quickly and efficiently. This level of speed and efficiency means that large numbers of cattle are able to be treated quickly, reinforcing its position as the most popular option for owners of large herds. 

The amount of drench required depends on the weight of the animal, and it is important to follow the correct drench ratio to avoid resistance. As per Australian regulations, all pour-on products come with application ratios, along with directions of use, safety data sheets and expiry dates.

Farmer drenching his cattle


Oral drenches are administered with an applicator, where the drench is delivered to the animal via its mouth before travelling down the throat. A head bail or crush is required for safe administration down the throat. This drench requires a bit more dexterity on the farmer’s behalf as one hand is used to open the mouth of the cow and the other to squeeze the applicator that allows the drench to go slowly into the throat. 

It is vital that the drench is administered properly. It needs to travel via the oesophagus, located at the back left, as this is where the stomach is located. Maladministered drench could travel into the animal’s lungs, potentially leading to death or severe illness. Care must also be taken not to damage the tongue, gums or throat during the process. 

As with pour-on drenches, the quantity required depends on the weight of the animal, and it is vital to always follow the manufacturer’s recommendations.

Farmer oral drenching


Injectable drenches are applied with a vaccinator or syringe to the neck or shoulders of the animal. Depending on the drench being used it can be administered to the skin or muscle of the neck. Again, the amount used depends on the weight of the animal. 

Only one dose is required, as more than this could cause serious illness or death. It is important the injection is administered properly as poor technique can decrease the efficiency of the drench, meaning that you need to purchase and use more, which in turn can lead to drench resistance. 

cattle drench injection

How Often Should Cattle Be Drenched? 

The answer to this all depends on your herd’s specific circumstances. What parasite are you treating? What kind of environment does your livestock spend their time in? What have the weather conditions been like recently? How old are your cattle? For example, drenching regularity varies widely depending on whether you are treating weaners, yearlings, or bulls. 

Common practice is to schedule drenching calves at weaning, while a follow-up drench a month later may be required on farms with a high worm burden. Weaners often have lower immunity than adult cattle and therefore require a repeat dose of drench. This is particularly true if they are suffering from other stresses and are living in damp, crowded conditions. 

As a general rule, the regularity with which cattle need drenching can be reduced by making improvements to their nutrition and placing them in pastures with a low risk of parasites.

This is why it is important to view cattle drenching as part of your wider herd management strategy so as to ensure that your herd is only treated at the appropriate levels, only using chemical drenches when necessary, so as to avoid the spread of drench resistance. All chemical treatments for internal and external parasites must be APVMA approved and come with directions of use and other information that can help producers with the frequency of use and correct dosage rates. If you are unsure, it is always wise to speak to somebody about the specific situation of your herd to determine the correct dosages and regularity needed. 


Can You Overdrench Cattle?

You may have noticed the many references to drench resistance patterned throughout this guide. This occurs when an insufficient amount of drench is administered and the parasites are still present in the cattle post-drenching. 

Having survived this initial drench, they are then better equipped to withstand later dosages. This is an increasing problem across Australia’s cattle population, meaning stronger drenches must be used, in heavier doses. 

As drench resistance occurs it is tempting to overdose your herd, however, overdosing is not a reliable response. Overdrenching cattle may kill some of these parasites but can lead to longer-term impacts on the health of the treated animals. 

It can be particularly dangerous to drench calves under the age of 8 weeks, as they will still be receiving some resistance to parasites via their mother’s milk. This is why we recommend weaning as the best time to drench calves. 

At the same time, it is important to stay clear of under-dosing. Not only will this not kill the parasites, but it is the surest way to lead to drench resistance, killing the most genetically susceptible worms but leaving behind a more drench-resistant parasite population.

For the long-term health of your herd, it is vital to find the correct balance between these two approaches. To avoid both resistance and poor animal health outcomes, it is always recommended that you should follow the directions of use supplied with the products and if you are ever in doubt, reach out to our customer care team for expert advice on individualised herd management.


What Is the Best Cattle Drench?

In the landscape of modern cattle management, the diversity of options means that there is no singular ‘best cattle drench’. From pour-on drenches to cattle dip and sprays to injectables and oral drenches, the best drench is the one that suits you and your herd’s circumstances. 

What to use depends on your management strategy, the set-up on your land and pasture, whether you require a meat or milk withhold, and your budget. Does the size of your herd require the speed of a pour-on drench or the precision and efficiency of an injection? 

At Specialist Sales, we offer all drench solutions to treat internal and external parasites at a price that suits all herd numbers, management strategies and budgets. If you need expert advice on treating your cattle herd, please contact our excellent customer care team.


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