One day the animal is fine, and the next day the foot is so sore the animal may not put weight on it.
Randall Raymond, director of research and veterinary services at Simplot, says foot rot is caused by opportunistic bacteria that require a break in the skin to enter the foot.
“The main one we deal with is Fusobacterium necrophorum, an anaerobic bacterium growing in the absence of oxygen.”
This pathogen is usually present in the environment; it is a normal inhabitant of the rumen and feces of cattle.
If they walk in areas contaminated by manure, they are susceptible to infection. Several other bacteria, including Staphylococcus aureus, E. coli and Actinomyces pyogenes, can increase the virulence of F. necrophorum and thus increase the incidence and severity of the disease.
Abrasions or punctures open the way for infection, so the best prevention is eliminating or reducing risk factors, according to W. Mark Hilton, clinical associate professor, Beef Production Medicine, Purdue University.
Prevention
Healthy feet and skin are less prone to cracking or snagging, so it helps to keep cattle out of mud. Feet that are constantly wet become softer and more vulnerable to damage.
“In summer, cattle often congregate in shady areas, where they defecate and urinate. Moisture and manure/urine compromise hoof health,” explains Hilton.
“You can’t always protect the cow from walking on ground that’s hard or frozen, or rocks that might scrape the skin.
So we concentrate on things we can prevent. We can eliminate boggy areas, for instance.” A boggy spring can be fenced off and the water piped to a trough where cattle can drink without standing in mud.
“If the area around a water tank is knee-deep in mud, build a concrete pad. Look for risk factors and see which ones you could eliminate,” he says.
“In the feed yard, we try to handle cattle with the least amount of stress, so they are not scraping their toes on concrete or getting abrasions on the sides of their feet by being jammed and struggling in the alleyways,” says Raymond. “We concentrate on moving cattle as quietly as possible,” he says.
“We use wood chips sometimes to improve footing and minimize areas in our facilities where there might be potential for trauma to feet.
We do everything we can to avoid muddy conditions, keeping pens as clean as we can,” he explains.
“We also try to select for cattle with good feet and leg structure. I believe this is very important.
There’s genetic predisposition for disease resistance (some cattle have stronger immune responses than others) and foot rot is no different, but good foot and leg structure is also crucial,” says Raymond.
“Good husbandry practices and genetic selection are key factors, along with good nutrition to keep the immune system, skin and feet healthy.
A good mineral program is part of keeping the immune system healthy. Our biggest issues here are selenium, copper and zinc deficiencies – these trace minerals are needed by the immune system in order to function correctly.
We strive for a balanced mineral program. Zinc and copper are also important to foot health,” he explains. If a herd has chronic foot rot problems, it would pay to work with a nutritionist to help solve these problems.
There is a vaccine for foot rot. “We haven’t used it in our operation, but one of the herds I work with in our area uses it and the owner feels it has reduced their incidence of foot rot,” says Raymond.
“They are now treating only one or no cases of foot rot per year, compared with about 20 cases per year before they started using the vaccine.”
The vaccine might be worth looking at, if a person has a high incidence of foot rot. “Just remember that husbandry and environmental management are a big part of the picture.
The vaccine can be a good tool, but should be looked at as just one part of the total management,” he says.
Treatment
The sooner you treat an affected animal, the better the chances of complete recovery. “We generally choose long-acting antibiotics (to minimize number of treatments), such as long-acting tetracycline or long-acting cephalosporin,” says Hilton.
“Penicillin is also effective, but lasts such a short time that you have to give it daily. Since foot rot can appear quickly and needs to be treated quickly, stockmen often keep the appropriate antibiotic on hand,” says Hilton.
Raymond says LA-200 has been the traditional treatment. “It has the right spectrum for these bacteria. The downside is that we only get 48 to 72 hours of therapeutic drug levels in the animal, so it may require a second treatment.
But LA-200 is economical and effective, especially if you catch foot rot early,” he says.
“Another antibiotic I often use is Excede, a ceftiofur that has a seven-day tissue level. We get longer duration of activity with just one treatment.
Excede is more expensive, so I tend to use this drug when the animal’s value is higher, or the condition more severe, or when I don’t think I’ll have another opportunity to treat that animal,” says Raymond.
In long-standing cases, the infection may get into the joints. The animal may develop septic arthritis, or cellulitis if it gets into the tendon sheath, and the animal must be culled.
“We usually don’t pursue aggressive treatment, but in seedstock animals with high individual value (and won’t be entering the food chain), we may do joint flushes.
It’s rare that we’d have to get this aggressive, however, because hopefully the producer noticed the condition early and treated it before it gets to this point,” he says.
Range cattle, however, may not be seen often enough to know when the problem started. In some cases there may be extensive damage by the time they are brought in for treatment.
“There may be no treatment that will completely cure the problem. We may just try to get the cow through that season, to wean her calf, and market her at a later time,” says Raymond.
“Those we catch early and treat appropriately probably have about a 90 percent success rate, if it’s truly foot rot.”
When treated within the first 24 to 48 hours, foot rot can usually be cleared up with one dose of long-acting antibiotic. Long-standing cases can be more challenging.
“I tell producers that foot rot will get better in about the same amount of time the animal was lame. If it’s been lame for three or four days, it will probably take three or four days to get better.
If the animal was lame for only one day, you can have a very positive response by the day after treatment,” says Raymond.
“Once the infection gets into the joint, there’s little hope of curing it with antibiotics, and the claw must be surgically removed,” says Hilton.
“If it’s a feedlot calf, he won’t have a long career and will do fine. I did numerous claw amputations in practice and also here at Purdue.
These calves go to market at 1,200 pounds, just like their herdmates. The owners are always amazed at how well they do,” he says.
“On an adult cow, with more weight and more traveling to do, we generally just try to get her through the season until her calf can be weaned, or get her next calf born if she’s in late pregnancy, and then send her to market.
For most cows, claw amputation is not a long-term solution,” explains Hilton. The animal will be impaired and unable to travel.
“If the animal has high value, however, it could be confined and manage to do all right. This might be the case with a valuable cow in an embryo flush program, or a bull that could be collected for A.I. breeding.
We address these on a case-by-case basis, depending on what the owner might want to try,” he says. 
PHOTOS
TOP: If an infection spreads to the joint, treatment with an antibiotic is less successful, and may require surgical removal.
BOTTOM: Foot rot cases can usually be cleared up with one dose of long-acting antibiotic when treated within the first 24 to 48 hours. Photos by Heather Smith Thomas.
