Editor’s note: First in a two-part series
Lameness in feedlot cattle can seem like a never-ending battle, but sometimes that may be due to misidentification of what is causing the lameness and/or handling and treatment protocols that aren’t effective.
USDA’s National Animal Health Monitoring System Feedlot ’99 study indicated that 92 percent of all feedlots reporting had at least one animal develop lameness following arrival to the feedlot, which accounted for 1.9 percent of all cattle on those feedlots. Though the study did not break out different types of lameness, it indicated that the overall medicine cost to treat one sick animal for lameness across all sizes of feedlots was $7.68.
Two of the biggest causes of lameness in cattle are toe abscesses and foot rot. Differentiating between these two conditions can mean the difference between ineffective treatment, wasted money and performance losses.
(Photo credit: Dee Griffin, DVM, MS) Rear view of a typical foot rot, a disease of soft tissues. Note the location and check for odor when investigating.
Toe abscesses are a common, significant cause of feedlot lameness that can be difficult to treat if not caught early and can cause performance losses, as well as further injury to cattle resulting in amputated toes, legs and animals being realized for salvage value.
The majority of toe abscesses are typically seen in newly arrived cattle anywhere from 4-14 days post-arrival. At this time, a lot of cattle arrive through sale barns, sorting barns and collection points. “We used to think we were causing them in the processing barn at the feedlot, but when you look at the time frame it takes for an abscess to form after an injury to the sole, it’s usually going to take four to 10 days before the pressure within the claw really starts to show up as a lameness,” says Tom Edwards, DVM, Midwest Feedlot Services, Kearney, Neb.
Brent Meyer, DVM, MS, Four Rivers Feedlot Services, Galva, Iowa, agrees and says toe abscesses tend to occur with 5-10 days on feed, and 7-10 days after re-implant in processing facilities that are not properly designed. “I think type of footing, cattle temperament and cattle handling are the three main components to a toe abscess problem.”
Toe abscesses can be a confusing cause of lameness because they can happen on front or hind feet and in inside and outside claws. Edwards sees most toe abscesses in the outside claw of the hind feet. Dee Griffin, DVM, MS, Great Plains Veterinary Educational Center, Clay Center, Neb., says there’s a propensity for toe abscesses to be in the front claw more than the rear, while Meyer adds that toe abscesses tend to be found on the inside claw on front hooves and outside claw on rear hooves.
Regardless of where it happens, “if you can feel swelling at the coronary band toward the front to the lateral one-third of the foot, you’ve lost the war,” says Griffin. “You now have an infection that’s up into the entire 3rd phalanx and is pushing into the 1st or 2nd phalanx, so you’re into the joint and it’s extremely difficult to recover at that point.”
Several things can contribute to the birth of a toe abscess. Edwards says rainy, wet conditions can soften up the sole, predisposing the foot to having problems. “It can happen if we’ve had a lot of snow and freezing conditions where we have sharp edges on the soil.”
Poor cattle-handling techniques and use of hot shots can cause toe abscesses when flighty or frightened cattle are moved too fast and tend to push off their toes to run or turn. Combine that with flooring that exacerbates sole problems, such as rough concrete or sanded concrete that literally grinds off hooves, and you’re ready for a toe abscess outbreak.
Diagnosis and treatment
Finding a toe abscess is as simple as using pliers and a rope. Securing the foot for a thorough examination is key. Next, applying pressure on the toe with a hoof tester or pliers will let you know if an abscess is working, Griffin says. “If it’s an abscess, it hurts and the animal will flinch or tighten its muscles.”
Meyer also instructs crews to pick up the foot and look for the obvious swelling and spreading between the toes, such as for foot rot. “Toe abscesses won’t swell up early in the process,” he says. “If one waits until the swelling is evident, then treatment response is not rewarding, and toe amputation usually results.” Like Griffin, he instructs crews to use hoof testers to check for pressure discomfort in the toe. “The affected toe will be very painful, and the calf will pull it away immediately.”
If an animal reacts to the pinch of the pliers, Griffin says, “take the nippers, understand where the white line is and cut a perpendicular tip off of that toe. If you get blood, you’ve opened up a site for infection and you’ve gone too far. Just look for a bit or a drop of a chocolate-covered exudate like hemolyzed blood in the middle of the white color.” If this is found, Griffin suggests nipping both toes on both feet. “If I have a pen outbreak, I put a 2-by-12 in the bottom of the chute, use a chisel like a post driver and take off the tips of all eight toes without damaging them.”
Overzealousness in treatment, however, can have bad results. “Every one of us was taught in veterinary school to dig these sole abscesses out and pack them and wrap them,” says Griffin. “These are cattle, and we’re not going to be wrapping their foot every day and putting them in dry stalls on bedding. They are going back in an environment that is not conducive to this. You need to leave an out for the abscess at the toe or it just gets worse. If you dig the bottom of those out, the bones underneath there will literally disintegrate. Once that infection starts up their leg, if it’s front leg, you have the option to amputate the leg at mid-radius and have a three-legged calf, but they are salvage value at best.”
(Photo credit: Dee Griffin, DVM, MS) The pencil marks demonstrate the approximate targets for trimming the hoof to relieve toe abscess pressure.