The introduction of Excede, a cephalosporin antibiotic from Pfizer Animal Health, brings a new method of administration for liquid antibiotics to the livestock industry. Their patented Ear Route of Administration injects the antibiotic into inedible tissue of the ear, which reduces the risk of injection site trim-outs.

“By injecting this antibiotic in to inedible tissue, there is no preslaughter withdrawal,” explains Dr. Robin Falkner, D.V.M., Senior Veterinarian with Pfizer. Injecting subcutaneously into the ear is similar to ear implanting techniques, says Falkner. The injection can go in the middle third or the top shelf of the ear. “I prefer the top shelf of the ear, because you don’t have as much going on in that part of the ear. We use the rest of the ear for tags, notching and implants, but typically only brucellosis tags are in the top shelf.”

Falkner says it is important to know the anatomy of the ear — where the arteries and veins are located — before administering any injection. Administration of Excede into the artery is likely fatal, and administration into the vein may cause bleeding. “If you fold the ear together, like a taco, the artery runs across the fold,” he explains. “This is an easy way to find the artery.” The injection can be placed a thumbs-width away from the fold to safely avoid the artery. During training, Falkner recommends wetting or clipping the ear so that the artery is easily seen.

Knowing the anatomy of the ear makes it easier to avoid blood vessels. Here, the arteries are represented in red and the veins in blue.

Properly restraining the animal is also important. “You don’t see much pain reaction to the injection,” says Falkner, “but proper restraint will help ensure the injection is given in the correct location. As with any injection, disinfect all equipment and scrape the area of any visible debris.

When injecting Excede into the ear, Pfizer suggests a special 16-gauge x 45º bevel needle. The 45º bevel needle helps deliver a subcutaneous injection, and is less likely to penetrate a blood vessel than a standard, sharper needle, Falkner explains. “A standard needle comes to a sharp point and allows easier penetration of an artery. The 45º bevel needle is not as sharp, providing an added safety factor to administer the antibiotic just under the skin.” Currently, Pfizer is providing these needles free of charge to Excede customers.

Using a special 45º bevel needle lessens the chance of penetrating a blood vessel in the ear.

Falkner cautions not to give other injections with the 45º bevel needle. “With less bevel, instead of slicing a slit in the skin, these needles can actually cut a plug of tissue on thicker areas of skin, like the neck, that could result in cross-contamination of tissue from animal to animal. However, with the thin skin of the ear, cutting a plug is not a problem.” Additionally, a 45º bevel needle would damage more surrounding tissue in a routine neck administration area than a sharper beveled needle.

As you are administering the antibiotic, Falkner says to look for a bleb of fluid under the skin. “If you see a bleb forming in the ear, you know you are injecting Excede under the skin, not in a blood vessel.”

Brochures and posters detailing proper administration techniques are available from Pfizer Animal Health in addition to on-site training. For more information on training, call 1-866-387-2287 or visit www.excede.com. ©

Administer the injection above or below the artery, just under the skin.

Watch or feel for a subcutaneous bleb to develop. Seeing the bleb helps insure you are not injecting into a blood vessel.