April 2015
Farm & Field

Fly Control ... NOW!

Both Rabon and Altosid act to disrupt the fly life cycle by preventing larvae from developing into adults.  

Introducing fly control products to your cows before flies appear will not only keep the pests under control but can increase your profits.

Those of you who have been reading my articles for the past 15 years have heard me talk over and over about how uncontrolled fly populations cut into your profits. However, if I can’t convince you this year with calves in the $300/CWT range, I never will! Research has documented an estimated 10-30 pounds in decreased weight gain per calf JUST FROM HORN FLIES. Assuming a price of $2.50/lb., this translates into a LOSS of $25-$75 PER CALF! Do I have your attention now?

Adult horn flies are dark gray and about half the size of the housefly. The life cycle is completed in 8-45 days depending on temperature and humidity. Horn flies tend to rest quietly on the back and shoulders of cattle until disturbed. Horn flies rarely leave their host except to lay eggs, to move to other cattle in the herd or when cattle enter buildings. Most feeding occurs along the underline of the animal and results in scabby, often bleeding, sores. Each fly may feed from 10-38 times each day! The irritation and blood loss causes reduced calf weight gain, decreased milk production and lowered sexual libido in bulls.

SWEETLIX and VMS feed-through fly control products containing Rabon Oral Larvicide or Altosid IGR are by far the easiest way to keep fly populations in check. These self-fed minerals, blocks or tubs are stress-free and require no additional labor and no cattle handling, unlike fly tags, sprays, pour-ons and backrubs. Blocks and tubs provide the additional advantage of not needing a special feeder and being able to monitor supplement levels from the comfort of your truck. An added bonus is that cattle (or horses*) receive complete mineral and vitamin supplementation in addition to fly control. No need to buy or maintain separate salt or minerals.

Both active ingredients, RabonandAltosid, pass harmlessly through the gut of the animal into the manure where it comes in contact with the fly larvae. (The fecal flies targeted* lay their eggs and go through their larval stages in the manure pat.) Both RabonandAltosidinterrupt fly life cycles by preventing the larvae present in the manure from maturing into adult flies each in their own unique way. Rabonkills fly larvae on contact while Altosidmimics the juvenile hormone, essentially never allowing them to mature into adults. Either method safely and significantly reduces the number of adult flies when used as directed. Neither Rabon nor Altosidhave slaughter withdrawal times and can be fed to all classes of cattle including lactating brood cows and calves. Additionally, Rabon is labeled for fly control in horses.*

For best results, start feeding the SWEETLIX or VMS fly-control product of your choice at least 30 days before the projected last frost (NOW) and continue feeding until 30 days after the first killing frost in the winter. In some areas, these dates will overlap. Horn flies emerge when average daily temperatures reach 65 degrees for a period of at least two weeks. Be sure to provide at least one mineral feeder or block per 10-20 head. Locate mineral feeders or blocks where cattle or horses congregate (near watering, loafing, shade areas, etc.). Increase or decrease the number of mineral feeders or change locations if necessary to adjust for proper consumption. Remember that neither Rabon nor Altosidwill kill adult flies so you need to place supplements out BEFORE you see flies for best control. If adult flies are already present when introducing SWEETLIX or VMS fly-control products, use an approved adulticide for at least one month to eliminate existing adult fly populations.

There are a wide variety of SWEETLIX or VMS self-fed fly-control supplements available through your local Quality Co-op. All are designed to meet a wide variety of nutritional and pricing needs. Visit www.sweetlix.com for more in-depth information on the various options available. You can also call 1-87SWEETLIX to speak with a nutritionist who can help you determine the best product for your specific situation.

In summary, NOW is the time to offer feed-through fly-control supplements for maximum effectiveness. A wide variety of self-fed SWEETLIX or VMS fly-control blocks and minerals are available through your local Quality Co-op location. Go by today and ask for them by name!

* Please see specific product labels for a complete list of flies targeted for control and the species of livestock the product is designed to supplement.

Rabon is a registered trademark of Bayer Animal Health

Altosid is a registered trademark of Welmark International

SWEETLIX and VMS are registered trademarks of Ridley Block Operations

Jackie Nix is an animal nutritionist with Ridley Block Operations (www.sweetlix.com). You can contact her at This email address is being protected from spambots. You need JavaScript enabled to view it. or 1-800-325-1486 for questions or to learn more about SWEETLIX mineral and protein supplements for cattle, goats, horses, sheep and wildlife. References available upon request.