How to treat lice in cattle

Lice infestations in cattle are a common issue faced by Australian cattle producers. Whilst tiny, these parasites can create huge repercussions for producers as the result of poor animal health, decreased feed efficiency, and weight gain, which impact the overall productivity and profitability of livestock operations.

Thankfully, there are several ways to control lice infestations in cattle, including effective pour-on treatments. To help you identify, treat, and manage cattle lice in your herd, we’ve put together this comprehensive guide.

What are cattle lice?

Cattle lice are small, wingless parasites that infest cattle, feeding on their blood, skin, or secretions. They are a common parasite in Australia and one of the key factors that affect cattle health and productivity.

Types of lice affecting cattle and how to identify them

There are two types of lice that affect cattle: biting lice and sucking lice.

Biting lice

Biting lice feed on cattle’s skin, hair, and secretions, causing discomfort and irritation. Unlike sucking lice, they don’t feed on the animal’s blood. As a result, they’re generally less harmful than sucking lice, but infestations can still cause significant health concerns like skin and hide damage and secondary infections.

The most common species of biting lice is a small, yellowish bug called bovicola bovis, also known as the cattle-biting louse. These lice tend to infest the neck, back, and tail regions of cattle.

Sucking lice

Sucking lice feed on the blood of cattle, piercing the skin and accessing blood vessels with their mouth parts. Sucking lice can cause greater health issues compared to biting lice, as their sucking can lead to irritation, blood loss, and potential anaemia in severe infestations.

There are two common species of sucking lice:

Haematopinus eurysternus: Known as the short-nosed cattle louse, this species is large and dark-coloured. It’s commonly found on the neck, shoulders, and back of the cattle.
Linognathus vituli: Also known as the long-nosed cattle louse, this species is smaller and often found on the head, neck, and loose skin hanging under the neck (the dewlap) of cattle.

The impact of lice infestations on cattle

Lice infestations pose a significant threat for both animals and producers for several reasons. Let’s explore some of the impacts of uncontrolled cattle lice infestations.

Itching and irritation

Lice can cause serious discomfort, which leads to frequent scratching, rubbing, and licking by the affected animal. This is often how producers first detect their herd is infested with cattle lice.

Hair loss: Intense itching and scratching can result in damage to the cattle’s skin, and subsequently, hair loss in the affected area. This can also do significant hide damage.
Reduced productivity: Infested cattle may experience reduced weight gain and decreased milk production over time, which has a direct impact on their productivity.
Secondary infections: When the skin is damaged extensively by cattle lice, the animal becomes more susceptible to bacterial infections, which are often transmitted through open wounds.

When are cattle lice infestations most common?

Lice infestations are typically more common during the cooler months, particularly in late autumn and winter in Australia. This is because cattle grow thicker coats during this time, which creates a favourable environment for lice to inhabit and thrive.

How do cattle lice spread?

Cattle lice are transmitted entirely through direct contact between animals. Lice and eggs can only survive for a few days without the cattle as a host, which means that good management practices are a crucial component of keeping cattle lice under control.

How to control cattle lice

There are a few methods that should be used concurrently to control cattle lice infestations in your herd, including regular monitoring, environmental management, and most critically, appropriate treatment in the form of pour-ons.

How pour-on lice treatments work

Pour-on treatments are a popular method for controlling lice in cattle as they are extremely effective when paired with good management practices. These treatments must be applied directly onto the skin of the animal along the topline. Upon application, the active ingredients in your chosen pour-on product will be absorbed through the cattle’s skin and distributed throughout the body to target lice and other parasites.

Advantages of pour-on treatments for targeting cattle lice

There are a few reasons producers opt for pour-on treatments over other alternatives to address cattle lice.

Ease of application: Pour-on treatments are easy to apply as they don’t require extensive handling or cause the animal significant stress.
Broad-spectrum efficacy: Many pour-on products are effective against multiple types of parasites, including lice, mites, buffalo fly, and internal worms.
Residual activity: Cattle lice treatments usually provide residual protection, which will prevent re-infestations for a specified time period.

Does pour-on ivermectin kill lice on cattle?

Ivermectin is an active ingredient found in pour-on treatments for cattle lice that works by targeting the nervous system of the parasite, leading to paralysis and death. It is effective against both sucking and biting lice, making it a versatile choice for cattle producers looking to keep their herds healthy.

Best pour-on products for lice treatment in Australia

In addition to ivermectin, there are several active ingredients that form the basis of popular pour-on treatments. When selecting a pour-on product for cattle lice treatment, it’s important to consider the efficacy, safety, and spectrum of activity.

Here are some of the best pour-on lice treatments in Australia, as recommended by the Specialist Sales team.

Ivermectin-based products

Ivermectin is a widely used active ingredient in pour-on treatments. Popular products include:

These ivermectin-based pour-on treatments have been proven to effectively control lice and other parasites in cattle, including internal parasites.

Moxidectin-based products

Moxidectin-based pour-on lice treatments offer broad-spectrum control against both internal and external parasites. As second-generation macrocyclic lactone endectocides, they are very effective in treating external parasites like lice. These products have a nil withhold period.

Some of the most popular products include:

Abamectin-based products

Abamectin is another ingredient for lice control that has garnered great results. It is similar to ivermectin, but may be more effective in certain situations including resistance to ivermectin. It provides broad-spectrum control against both external and internal parasites, including cattle lice species.

Go-to products include:

Synthetic pyrethroid-based products (permethrin and deltramethrin)

Synthetic pyrethroids such as permethrin and deltamethrin are commonly-used actives in pour-on treatments. They are effective against lice and other external parasites, but do not have activity against internal parasites.

Well-known permethrin products include:

Deltamethrin-based pour-ons can offer rapid, extended knockdown protection against lice and mites, but they are only effective against external parasites.

We recommend deltamethrin products including:

How to choose the best treatment for lice on cattle in Australia

To select the best treatment for cattle lice infestation, you’ll need to consider several factors, including the type of lice present, the overall health of the cattle, and the specific needs of your farm. Let’s explore some key considerations.

- Type of lice: It’s important to first identify whether the infestation in question is sucking or biting lice, as this will influence your choice of treatment. Use common indicators like size and colour to determine which species you are dealing with before selecting an appropriate pour-on product.
- Resistance management: If you have already used a pour-on treatment on your herd, this will impact the next product you choose. Rotate between different classes of active ingredients to reduce the risk of resistance development.

Animal health: Consider the health status of your cattle, as poor health or specific health conditions may constrain you from using certain treatments.

Environmental conditions: Weather conditions can impact the effectiveness and persistence of treatment. If dealing with unpredictable conditions, you may need to utilise more than one type of pour-on treatment over time, or opt for a more effective treatment to mitigate the impact of poor weather.

Tips for effective cattle lice treatment

To ensure your pour-on cattle lice treatment is as effective as possible, we’ve rounded up our top implementation and management tips.

Time your treatment around infestations: The best time to treat cattle for lice is during late autumn or early winter, around the same time infestations are most likely to occur. This will help to reduce lice populations before they reach peak numbers.

Focus on proper application: Ensure that your pour-on product is applied correctly, along the animal’s topline from the shoulders to the tailhead. This will guarantee even distribution and maximum efficacy.

Use an accurate dose: Always follow the manufacturer’s dosage recommendations carefully. Underdosing can lead to ineffective treatment and cause resistance to the active ingredient over time, whereas overdosing could be harmful to your animals.

Reapply as directed: Some pour-on products may require reapplication after a certain period for continued efficacy against re-infestations. Check the product label for specific instructions for your chosen pour-on cattle lice treatment.

Employ good environmental management practices: As well as treating animals with pour-ons, it’s important to manage the surrounding environment to reduce the risk of re-infestation. This includes biosecurity measures (e.g., appropriate fencing and keeping animals separated) as well as pasture management.

While lice infestations can pose a challenge to cattle producers, with the right approach and products, they can be effectively managed. Pour-on treatments, especially those containing ivermectin, abamectin, moxidectin, and synthetic pyrethroids, offer convenient and efficient solutions for controlling lice. By following best practices for application and considering the specific needs of your herd as part of a comprehensive management strategy, you can ensure the health and productivity of your cattle against cattle lice.

Shop pour-on treatments for cattle lice containing a range of popular active ingredients. If you need advice on which products to choose, our team will be happy to help – contact us to chat. When treating infestations like cattle lice, always consult with a veterinarian or animal health professional to ensure you are selecting the right course of treatment for your animals.