While the current weather is helping to reduce lice issues in sheds, a mild and damp autumn and housing season has resulted in bigger than normal lice and mange burdens in sheds this winter.

Stock that were treated three to four weeks post-housing are now showing signs of reinfestation in some areas, especially on farms that were housed earlier.

Cattle that lick themselves is a sure sign of lice or mites and while it may look harmless, it can cause severe discomfort to cattle. Anything that is going to cause stress or discomfort will also have a negative effect on daily liveweight gain.

There is no point in going to the trouble of delivering an expensive, high-quality winter diet if you do not have animals with a clean bill of health that can perform over the housed period.

Treatment

Typically, a pour-on product is used for treating lice. However, be aware that not all products will cover for both biting and sucking lice, so choose the product carefully.

The two types of product that are designed to treat lice and mites are either synthetic pyrethroids, which are a pour-on or spot-on type product, while the second group of products are the clear drenches or ivermectin-based products, also available as a pour-on or as an injectable.

Injectables are not as good at treating biting lice, so a pour-on product is better where they are an issue.

When dealing with pour-on or spot-on products, it is important to apply them as directed on the label, as spot-on products require the entire dosage to be placed on to the skin in one area of the animal, while pour-ons need to be applied evenly along the spine of the animal.

Delivering the correct amount of product is also important, so knowing the weight of the animal being treated is critical.

For any stock that are due to be slaughtered in the coming weeks and months, make sure you are aware of withdrawal period of the product being used.

Hatching

When treating animals for lice, it is important that animals have been housed for at least three weeks, as you want all the eggs to have hatched prior to treatment.

Also, all animals in the shed must be treated at the same time, as lice will jump from an infected animal to a treated animal.

Take the opportunity to clip cattle’s back if they are yet to be done. While it is not necessary for the product to work, it will ensure the product make contact with the skin of the animal as soon as possible after application. It also reduces the thermal cover for lice, which in this hardier weather will also help to reduce numbers.

Clipping cattle has also been shown to help increase feed intake, as animals that are clipped are able to lose more heat than those that are not.

This will help maximise the amount of silage cattle are eating, which will help to maximise liveweight gain over the winter period.