There are many different causes of lameness in both the cow-calf and finishing sectors of the cattle industry. Making the correct diagnosis or recognizing specific clinical entities will alter treatments that are given.
Remember, lameness is the symptom caused by pain. We need to find the cause of that pain.
Pain control may be justified in many cases to either help with recovery or ease the pain until other things can be done.
There are both infectious and non-infectious causes of lameness.
Trauma and injury are examples of non-infectious causes of lameness, so antibiotics are often not necessary.
Sometimes waiting one day will see resolution of lameness such as a sprain strain or sole bruise.
Most producers diagnose lameness as foot rot and give antibiotics. Some recover but many don’t because foot rot isn’t the problem.
The first advice with a lame animal is to have as good a look as possible, both when the animal is walking and then in the chute, where the entire leg is checked over and the foot lifted up.
Classical signs of foot rot are a swollen foot with toes spread apart and often an open, smelly wound between the toes. Cattle will often respond nicely to the area being cleaned and then one course of antibiotics prescribed. If they don’t, it is most often something else.
Digital dermatitis is increasing in incidence in wetter conditions on some farms and feedlots. These cattle are extremely sore, especially over the back of the foot into the heel bulbs. They often try and walk on their tiptoes to prevent the back of the hoof and heel bulbs from touching the ground.
They can become chronic and hard to treat, but veterinarians may recommend tetracycline sprays or bandaging with tetracycline antibiotics and potentially the use of footbaths. However, wraps must be removed in a day or two because they can hold in moisture and worsen the condition.
Toe-tip necrosis is another primarily feedlot lameness, and it develops just how it is described.
The bony end of the last bone in the toe becomes necrotic or dead and causes tremendous pain over the end of the toe and almost a three-legged lameness.
This condition is more often seen in fractious cattle, and it may start with transportation or processing of cattle.
I am convinced that we have made traction a top priority in our chutes and alley systems. The struggling and pushing against these rigid traction bars may pull away the sensitive part of the toe. The hoof gets lifted off and the process starts. These become chronic and severely lame, and removing the tip of the toe to facilitate drainage may get results.
Foot rot and digital dermatitis can be seen relatively easily, but toe tip necrosis is harder to find. Some veterinarians are even amputating the toe on a case-by-case basis with good results.
The last three examples — foot rot, digital dermatitis and toe tip necrosis — all have vastly different treatments and prognosis. Your veterinarian may often need to help you diagnose them, and the cases require individual treatment, time and attention.
Dr. Karin Orel, an experienced bovine veterinarian at the University of Calgary’s veterinary medicine school, recently gave a great presentation about helping producers make a diagnosis by watching the type of lameness.
Close examination of an animal’s feet and legs when lameness is detected is critical to making the correct diagnosis.
A good video of the lameness will definitely help because it can provide a later comparison to see if the lameness is improving.
Even cattle’s facial expressions can help determine if the lameness is painful.
Lameness creates one of the highest levels of pain, so painkillers are often part of the treatment prescribed by veterinarians.
Painkillers are now approved for injectable, oral and pour-on use, each with different withdrawal periods. It could be argued that painkillers facilitate healing and recovery more than antibiotics do.
Cleaning a foot rot wound and allowing in air will kill the organism, while administering a topical and not parenteral tetracycline is more effective with digital dermatitis. Toe tip necrosis is treated with drainage and possibly toe amputations.
The straight sole abscesses that we often see in dairy cows and breeding beef bulls also clear up rather quickly once drainage is established. You may see cattle throwing the lame leg in or out trying to avoid weight on the affected claw.
Other lameness issues may be the result of joint infections often caused by Mycoplasma or histophilus, two micro-organisms that can also cause pneumonia. Your veterinarian may need to culture these joints to identify the bug, and while recovery is not likely, preventive measures may be available for the rest of the herd.
Trauma and/or nerve damage round out most of the common causes of lameness in most cattle.
Mature cows and bulls can develop bad cracks, corkscrew and other hoof deformities as well as interdigital fibromas (corns).
Again, careful observations will allow these issues to be detected, and your veterinarian or a good hoof trimmer may be able to improve the situation.
Septic arthritis of the last joint underneath the hoof results in a severely lame cow or bull and often requires claw amputation or drilling out the joint by a veterinarian under anesthesia so that it will fuse. This will result in a sound animal with an enlarged claw.
Roy Lewis works as a technical services veterinarian part time with Merck Animal Health in Alberta.