Controlling pain is important for the health of all animals, including food-producing animals. Banamine Transdermal is approved to control pain associated with foot rot in cattle, a common cause of pain and lameness in cattle of all ages and breeds. The disease is seen in cattle that are housed in barns and feedlots and those out on pasture. Banamine Transdermal contains flunixin, a veterinary nonsteroidal anti-inflammatory drug (NSAID). Several NSAIDs are FDA-approved to control pain in cats, dogs, and horses, but Banamine Transdermal is currently the only NSAID approved to control pain in a food-producing animal.
Foot Rot – A Painful Disease1
Foot rot is caused by bacteria that invade the foot through a break in the skin between the two toes. (In cattle, each foot has two toes.) The bacteria need some sort of injury, such as a cut, puncture wound, or severe abrasion, to penetrate the natural barrier of the skin. Walking on rough surfaces, such as sharp gravel, rocks, and hardened mud, or standing in a wet and muddy area for a long period of time can cause foot injuries in cattle.
Once the bacteria enter through the damaged skin, they move down into the underlying tissue and begin to quickly multiply and secrete toxins. As the infection worsens, the foot tissue starts to decay. In severe cases, the foot will abscess above the hoof, revealing a foul-smelling discharge. If the infection isn’t treated, the bacteria may invade the deeper tissues and even the joints and bones of the foot, resulting in permanent lameness.
The bacteria that cause foot rot are common in the environment, especially in shady or wet areas. Not only can the bacteria be found on diseased feet, they can be found on healthy feet, as well as in the manure of cattle. Once the bacteria are “seeded” in the soil, foot rot may recur in a herd for a long time.
Lameness due to pain is typically the first sign of foot rot, and is usually accompanied by other signs of inflammation, such as swelling and redness. As the swelling progresses, the toes begin to separate. The swelling and lameness can appear suddenly, with the animal walking normally one day and lame the next. Cattle with foot rot can lose weight because they’re reluctant to walk to their feed and water. They also may have a fever and loss of appetite.
Fortunately, prompt treatment of foot rot with an appropriate antibiotic is usually successful. If treatment is delayed, the prognosis is poor. Some mild cases will respond to topical therapy or get better spontaneously without treatment, but most cases require an oral or injectable antibiotic. Several antibiotics are FDA-approved to treat foot rot in cattle. After the antibiotic treats the underlying infection, the pain eventually subsides, but Banamine Transdermal can control the pain even before the antibiotic takes effect.
As for any veterinary NSAID, Banamine Transdermal is only available by prescription. A veterinarian’s expertise is required to diagnose foot rot, determine if Banamine Transdermal is appropriate for the animal, and treat any side effects if they occur. The drug is a topical solution and applied only once in a narrow strip along the animal’s back and is absorbed through the skin.
People who handle Banamine Transdermal (mainly veterinarians and cattle producers) should wear personal protective gear that covers their eyes and skin to prevent contact with the drug that could cause potentially severe eye damage, skin irritation, or drug absorption through the skin. The drug’s label includes detailed information about user safety and animal safety, including what to do if a person is accidentally exposed and the potential side effects in cattle.
Banamine Transdermal is also approved to control fever associated with another disease in cattle called bovine respiratory disease (BRD). See Animal Drugs @ FDA for more information about Banamine Transdermal.
Hard to Detect Pain in Food-Producing Animals
A major challenge in showing that a drug controls pain in animals is that, unlike people, animals can’t verbalize where they hurt or their level of pain. Companion animals, such as cats, dogs, and horses, typically live more intimately with their owners than food-producing animals, so their pain behaviors may be more noticeable and easier to detect. But in prey species, such as cattle and other food-producing animals, pain can be particularly hard to detect. In the wild, any outward signs of sickness or weakness will be quickly detected by a predator. A limping, painful bison will be the first one in the herd killed by hunting wolves. To survive, prey species like cattle have evolved to mask their physical signs of pain, making it hard for veterinarians and cattle producers to tell when they’re in pain.
Another complicating factor in detecting pain in food-producing animals is the variability in how they express pain. Not only does this variability extend across species, it also extends across breeds within a species, across animals within a breed, and across procedures and diseases. For example, one cattle breed may express pain differently than another breed, and one animal may express pain differently than its herd mate with the same disease. Also, the pain behaviors seen in an animal with one disease, such as foot rot, are often different than those behaviors seen with other painful diseases or after surgery. An animal’s pain behaviors may even change according to the time of day.
“Although it has been challenging, researchers have made significant progress in establishing reliable ways to detect and measure pain in food-producing animals,” explained Emily Smith, a veterinarian and drug reviewer at FDA’s Center for Veterinary Medicine (CVM). “Validated pain scales and objective measures of pain are important tools to enable us to determine if a drug is effective at controlling pain in food-producing animals.”
Measuring Pain Associated with Foot Rot in Cattle
Reliable and validated methods for assessing pain are necessary to determine if a drug is effective at controlling pain. To show the effectiveness of Banamine Transdermal at controlling pain in cattle with foot rot, the drug company conducted a study that used both subjective and objective measurements. For the subjective measurement, a person experienced with cattle observed each animal several times during the study and assigned it a lameness score of 1 (normal gait) to 5 (severely lame). For the objective measurement, cattle walked across a pressure mat several times during the study to measure the maximum force and contact area of the foot with foot rot.
The study included two groups of cattle with foot rot. One group was given Banamine Transdermal and the other a saline placebo. Six hours later, the cattle treated with Banamine Transdermal had improved lameness scores and walked with increased maximum force and contact area across the pressure mats, indicating they were less painful than cattle given the saline placebo.
Committed to Animal Health
CVM continues to work with drug companies and collaborate with other researchers to develop new ways to reliably measure pain in food-producing animals and their response to treatment. For example, the center is collaborating with a group of researchers, led by the American Association of Swine Veterinarians, on a research project to validate endpoints for measuring pain after surgical castration in piglets.
“Having approved drugs, such as Banamine Transdermal, available to control pain in food-producing animals is a positive contribution to veterinary medicine,” said Beth Luddy, a veterinarian and the deputy director of CVM’s Office of New Animal Drug Evaluation. “CVM is committed to improving animal health by making sure safe and effective drugs are available for all animals.”
(1) Step DL, Whitmore B, Giedt EJ, Lalman, D. Foot rot in cattle. Oklahoma Cooperative Extensive Service, ANSI-3355.
(2) Van Metre DC. Pathogenesis and treatment of bovine foot rot. Vet Clin Food Anim 2017;33:183-194.
(3) Whittier WD. Foot rot in cattle. Virginia Cooperative Extension, Livestock Update, January 1999.
Resources for You
- From an Idea to the Marketplace: The Journey of an Animal Drug through the Approval Process
- T.A.L.K. Before You Treat
- Veterinary Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)