FROM THE FARM REPORT: MA’AM, I’M GOING TO NEED TO SEE SOME IDENTIFICATION

Ear tags serve multiple functions in modern dairy management, ranging from individual animal identification to health monitoring and parasite control. While visual and electronic identification tags are essential for tracking and data management, insecticide-impregnated ear tags are increasingly used for controlling fly populations that negatively impact dairy cattle. This article provides an overview of the various types of ear tags used in dairy cattle, with a focus on insecticidal tags, their efficacy, and best practices for use.

Ear tags are among the most versatile tools in dairy herd management. As of November 5, 2024 the USDA ruled that all cattle must have a combination of visual and electronic components tag. This process allows the products from those animals to be traced back to its farm of origin, should the need arise. The visual aspect of the ear tags are typically numbered for easy on-farm identification and the electronic identification (EID) tags are useful for tracking individual health, production values, and medical history. Currently, the 840 RFID technology is the most widely used to satisfy the federal rule and to track the information it provides.

Another type of ear tags are medicated or insecticide-impregnated tags. These fall into a more specialized category of tags which deliver a slow, sustained release of chemicals over the course of three to four months to kill or repel flies. These tags provide an intervention strategy to control external parasites such as horn flies (Haematobia irritans) and face flies (Musca autumnalis). Both of these pests are known to impair animal welfare and milk production.

Studies have shown that insecticide treated ear tags significantly reduce pest swarms on cattle. For example, tags treated with permethrin provided up to 95% control of horn flies over an eleven week period. However, face fly control was somewhat lower at 49% effectiveness. Another study found that tags treated with diazinon reduced the burden from buffalo flies (Haematobia irritans exigua) by 96% for up to twenty weeks. These flies are located in the Eastern hemisphere and are closely related to horn flies (Haematobia irritans). Additional results highlighted positive effects on weight gain for beef cattle and found minimal residue concentrations in the butterfat of lactating dairy cows (0.01 — 0.04 mg/kg) (Spradbery et al., 1996). For food producing animals it is important to follow the instructions closely and check with a veterinarian to be sure what brand is right for a herd. These tags are most effective when applied at the start of fly season, typically late spring, and should be removed by fall to prevent the flies from building a resistance against insecticide.

In conclusion, ear tags are valuable tools in both dairy and beef operations, not only for identification and data management, but also as part of integrated pest control strategies. Beef animals and dairy heifers out on pasture may benefit from the use of the insecticide tags as a means of alternative fly control. Insecticide ear tags offer a convenient, cost-effective way to manage external parasites that impact milk yield and animal well-being. When used correctly and as only during peak fly season, they can help support healthier and more productive cattle herds.

— Sommer Thompson

sthompson@whminer.com