Injectable vs. Pour-On – Which One is Right For Me?
By: Terri Queck-Matzie
Controlling internal parasites in cattle is serious business. A variety of products are available – in a variety of forms. Choosing the right solution for your operation can be challenging.
Dr. Sonja Swiger, Livestock Veterinary Entomologist with Texas A&M AgriLife Extension, says factors to be weighed are time, labor, cost, and effectiveness.
Key to effectiveness is making sure each animal gets the required dose for its weight. “Your vet will most likely prefer injectables, because the dosage can be closely controlled,” says Swiger. “You can be sure each animal gets exactly what they should.” Under dosing can lead to parasites developing resistance, a problem in years to come.
Injectables require clean syringes and needles. Always withdraw medication via the needle through the rubber stopper on the bottle. Never open the bottle for risk of contamination that can cause infection at the injection site. Injections should be given under the skin of the neck, not into the muscle, and not into the hindquarters.
Injectable treatments are more expensive than pour-on varieties, and will require containing the animal – adding labor to the cost.
But they can be more effective due to the controlled dose, and new products claim to require only one injection per year. Depending on the specific product, injectable medications can also control liver flukes as well as common varieties of stomach worms.
Pour on treatments generally require two or more doses per year, and dosage for each individual animal may be inconsistent. However, they are less expensive and require less cattle handling.
Care must be taken not to get medication into the lungs due to risk of pneumonia, and timing with the weather can be critical. “You don’t want to treat animals right before it rains, or the medication will wash off,” cautions Swiger.
She says geographic location is a factor in deworming protocol. More humid climates, like the Southeast and parts of the Midwest, have higher moisture counts favored by parasites. While the dry Southwest creates a less hospitable environment. “There you might be able to get by with only treating once per year,” says Swiger. “In the moist areas, you will probably need to treat at least twice.”
She also says it is good to rotate products to reduce risk of developed resistance.
Reducing pasture contamination is also important to parasite control. High densities of grazing cattle or re-use of the same pastures year after year can result in highly contaminated forage. Timely deworming prior to the grazing season will greatly reduce the subsequent contamination of pastures once cattle are turned out.
Pregnant cows dewormed in the fall can expect to winter better, wean heavier calves, and have higher conception rates the next season. Some products should not be used during the first 45 days of gestation.
Be sure to thoroughly read all product labels, and, as always, check with your veterinarian for the best approach for your location and herd.