Summer parasite controlThis spring’s historic price rally rapidly settled into a summer slump. You’re now facing increasing production costs that are eating away at your profit margins. Cutting expenses is one option, but adding value and performance to your cattle may be the most beneficial strategy.

Adding value to calves can involve a variety of management practices, yet the most effective way may be the simplest — parasite control.

Mid-June is a good time to reevaluate your parasite-control program. If you haven’t already dewormed calves and stockers, consider doing so now. And June is the time to make sure your fly-control measures are in place and effective because fly numbers will rapidly increase through July and August in most regions.

Measure costs

Increasing production costs for feed and fuel may tempt you to cut back on management practices such as parasite control. Ranch business analysts have one word of advice — don’t. They stress that the key to managing through cost increases is the ability to measure your cost of production.

 “There is no way to know which costs to cut if you aren’t measuring all of the cost categories for your ranch,” says North Dakota State University beef specialist Greg Lardy.

Ranch business coaches suggest that as profit margins narrow you should avoid the temptation to cut back on animal-health and preconditioning programs. Cutting your animal-health program can leave your cattle open for disease risk, and sick cattle don’t perform well. It’s always cheaper to prevent disease from occurring than to deal with a disease outbreak. And veterinarians agree that cattle suffering from internal and external parasites are more prone to disease.

Summer parasite controlIf you dewormed your calves along with the cows this spring at grazing turnout, veterinarians suggest doing so again about 90 days into the grazing season, or when calves weigh about 200 pounds.

Texas A&M University veterinarian Thomas Craig says there is no magic date for spring deworming, as conditions vary from ranch to ranch and year to year. The “best” time depends on calving season, weather, forage growth and an operation’s management schedule. He stresses the importance of working with a veterinarian who knows your area and who can help plan a treatment schedule that works for your ranch.


Summer parasite controlWhether or not you retain ownership of your calves this fall, you can reap the added value of deworming. Veterinarians say the most important reason to deworm is to improve the health of those calves. But also important is, if you hold those calves for 45 days or more during a preconditioning program, the weight gain on those cattle will more than pay for deworming.

Many producers are considering aiming their production toward one of the natural marketing programs, or one that does not allow the calves to be implanted. Deworming those calves can help ensure gains for cattle where implants cannot be used, and deworming does not eliminate cattle from natural programs.

In one study that showed the benefits of deworming at or near spring turnout, herds were treated at zero and 10 weeks, at three and 10 weeks or not treated at all. The herd treated at three and 10 weeks showed a weight advantage of 43.56 pounds over the control group; the zero- and 10-week group showed a 32.66-pound advantage.

An analysis of prices paid for preconditioned calves sold at auction shows feedyards willing to pay $6 to $10 per hundredweight more for those calves. But premiums don’t reveal the complete advantage. Returns to cow-calf producers from preconditioning are $50 to $75 or more per head, depending on sales price, according to university research. Half of those premiums are found in price premiums, and half are found in additional weight of calves. And one of the most cost-effective ways to add weight to your calves is to eliminate their parasite load.

By eliminating that parasite load, you’ll also ensure that the vaccines have the best opportunity to work effectively. Parasite control as part of a preconditioning program, therefore, adds value for you and your customer.

Fly control

The economic loss due to fly infestations in cattle is well documented, so you should not wait until a problem exists to begin a fly-control program. There are three major ways that flies reduce performance: through reduced grazing (because cattle are searching for a way to ease the irritation), as a result of sucking blood from the cattle, and through spreading disease. Veterinarians say a good program needs to be in place before fly numbers increase.

Proper identification of the fly and knowledge of the life cycles are important to help target control measures. Horn flies and face flies are the two main species that affect pastured cattle. Although the most effective means of controlling them are primarily chemical, a variety of application methods exist. Equipment and facilities will dictate which measures are best.

Normal populations of horn flies usually average several hundred, but as few as 50 flies per animal can be enough to negatively impact performance. Thousands can occur and that many can consume enough of the cattle’s blood to make them become anemic. Horn flies can also transmit the causes of blood-borne diseases like anaplasmosis.

Face flies more closely resemble houseflies. They concentrate around the eyes, nose and mouth where they feed on the mucosa found in those areas. Since face flies congregate around the eyes and can carry the causative agent of pinkeye, controlling them can help slow or limit the spread of pinkeye. The spread of pinkeye by face flies makes their economic impact two-fold. The disease reduces average daily gain in calves and performance of cows but also reduces the value per pound of calves at marketing due to eye problems.

Several methods, and many products within those methods, are available to control flies. These methods include slow-release ear tags, sprays, rubs, dusts, feedthrough and boluses. The most common methods seem to be ear tags, sprays and rubs. The chemicals that these methods deliver include pyrethroids, organophosphates, organochlorines and endectocides. 

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