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Timing is key for effective use of cattle oilers

Animal Health with Roy Lewis: There is a recommended window for when control products should be used

Cattle oilers are effective for controlling parasites, but only use insecticide for a limited time during the season — long enough to control the pest, but short enough to reduce risk of insecticide resistance.

In light of the ever-increasing issues with lice and flies affecting production in our beef herds on summer pasture, it’s a good time to review cattle oiler pros and cons and suggest a bit on maintenance and a few tips for better utilization of oilers in the battle against these two underestimated parasites.

Cattle oilers or dusters need some capital input but if utilized with proper timing for lice and fly control, they reduce production losses caused by these parasites. If used in conjunction with the placement of mineral stations sited in different parts of the pasture, they can also help improve pasture utilization.

I think the first general principle is that oilers need to be properly maintained. Pumps need to be checked for any leaks and repaired if necessary. Overall the cattle oilers can be utilized for lice in either the late fall or winter and for flies at specific times in the summer.

(I am most familiar with the Lewis and Hutton brand oilers and have been asked many times over the years if I am related to the Lewis oiler group and I have to say unfortunately I am not. And there are several good brand-named oilers on the market).

The cattle oilers are generally made very robust and will last many seasons. Parts can be replaced, helping to purchase of an oiler a long-term investment.

Proper products, proper timing

It is important to use insecticides approved for the job at hand and approved for use with specific mixing instructions. The carrier should either be canola or mineral oil. We need to get away from the old practice of mixing insecticide with diesel fuel from an environmental standpoint but also for potential of residue in the carcass. I have said many times that I have never seen a slaughter withdrawal time for diesel fuel, but there should be one.

The other principle for parasite treatment is to include pesticide in the oiler for one life cycle of the parasite, or only during the peak times. For example, if doing a macrolide or other lice parasite treatment in winter, then pick a time when most appropriate for your herd and treat with the cattle oiler product for one month.

It is fine to use the oiler as a groomer with straight mineral or canola oil year-round, but you only want to include the insecticide in the oiler for one month for effective control. This is doubly important as you save excessive use of product and reduce the risk of the parasite developing resistance to the treatment.

Similarly, there are times during fly season in the summer when producers are running cattle through a chute and have treated cattle with either a pour-on product, attached fly tags in their ears, or perhaps fed an organic fly-control product in the minerals.

If any of these other highly effective fly-control measures is being used, then again use the oiler with straight oil but leave out the medication. There is absolutely no need to treat unnecessarily. You should also monitor flies and only start when fly numbers reach about 200 flies per head before initiating treatment. Efficacy will be very high and economic gains will result.

The medications for the oilers are generally a permethrin-based products such as Ectiban or generic equivalents, and are effective against lice, flies and ticks. The broad-spectrum treatment controls several pests, but the issue as noted earlier, you want to treat for different pests at different times of the year — flies in midsummer, and lice in late fall or winter months. Ticks often can be controlled in early spring, so producers need to manage treatments to coincide with these times.

Use the right products

Having oilers in bull pens will encourage grooming and some units also have brushes for cattle to rub against. Rubbing and grooming themselves will help remove the lice and ticks. So again there are multiple benefits from keeping the oilers with cattle for all or a good part of the year.

At one time there were other oiler pest-control products containing things such as malathion and lindane but they have been removed from the market and are not to be used.

Don’t try to adapt products to work in an oiler unless they specifically have a label and mixing instructions calculated. Manufacturers of approved products have figured out normal cattle usage and the dilution required to get proper application. Veterinarians cannot prescribe an off-label usage for insecticides. Most products have a shorter withdrawal to no withdrawal depending on the product, but always read the label very closely before making a shipping decision.

The use of oilers with recommended products at the appropriate times benefits cattle and help us prevent resistance from developing against either flies or lice. We have known for a long time about flies developing resistance to certain control products, but with an increasing number of lice outbreaks, it appears lice are developing resistance to products as well. Once you get cattle through the winter lice will more or less disappear over the summer.

Here’s to a great pasture season this year and hopefully better utilization purchase and maintenance of cattle oilers.

About the author


Roy Lewis is an Alberta-based veterinarian specializing in large-animal practice. He is also a part-time technical services vet for Merck Animal Health.



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