WARMER weather and wet conditions can create the perfect environment for lameness-inducing bacterial infections in cattle, according to Gregg Hanzlicek, veterinarian with Kansas State University's Veterinary Diagnostic Laboratory.
He recently shared tips for preventing, identifying and treating two of the most common foot diseases: foot rot and hairy heel warts.
Foot rot. With a reputation for causing headaches for producers in the livestock industry, foot rot accounts for most cases of lameness in pastured cattle, explained Hanzlicek. The infection is caused by bacteria present in the rumen of healthy cattle and found naturally in the soil.
"We can sample cows and calves without foot rot, take a swab of their feet, and we are going to find these bacteria," Hanzlicek said. "They're everywhere."
If the skin's integrity is there, these bacteria cause no problems, he said. So, for cattle to develop foot rot, the skin must be broken.
"It's probably not a big deal if we have a cow or two with foot rot, but if we have a bull out there that's lame with foot rot, we know our breeding efficiency is likely to go down," Hanzlicek said.
During the summer heat, cattle are often found standing on muddy pond banks, which can weaken the integrity of the skin and allow for infection. Foot rot isn't limited to wet conditions, however; the infection can become a problem in just about any environment.
"Extremely dry conditions that let the skin crack can bring on foot rot," Hanzlicek said. "Sharp rocks, corn stubble later on in the fall and even frozen ground as we get into the wintertime can bring on foot rot."
The first signs of foot rot are subtle swelling and lameness, and it can be hard for producers to spot.
"Early on in the disease it's symmetrical, meaning the entire area above the hoof wall will be swollen," Hanzlicek said.
He added that leaving the condition untreated could compromise treatment later on because "it will advance into more chronic stages, where the tendons and the tendon sheath within those feet will become infected."
The key to successfully treating foot rot is catching it early, Hanzlicek said. Producers should remember that if they have a lame cow or bull and the lameness is in the foot, foot rot is a likely culprit.
When it comes to treating foot rot, Hanzlicek said there are a few options.
For instance, there are "several good injectable antibiotics labeled for cattle for foot rot," he said. If producers choose to use a product not labeled for foot rot, a veterinarian's prescription is required.
Preventing foot rot is easier in drylot conditions versus open pasture, Hanzlicek said. A producer's best opportunity for prevention is providing 2-4 oz. of trace mineral per day.
"The two minerals we're most concerned about or that have the biggest play in skin integrity are zinc and copper," he said.
Hanzlicek suggested that producers provide the necessary trace minerals and practice other preventative methods before resorting to the foot rot vaccine that is available since there has been some question regarding the functionality of the vaccine.
"I know of no controlled trials that showed it's effective," he said. "If you're doing everything you can and you have a foot rot problem and want to add the vaccine, talk to your veterinarian."
Hairy heel warts. Although hairy heel warts wreak the most havoc in the dairy industry — plaguing an estimated 70% of dairy operations — it's an affliction that could become more of a problem in the beef sector, Hanzlicek said.
"It's not common in pastured cattle, but we are getting calls from producers saying it's in the cow/calf industry today," he said. "So, we look at it as more of an emerging disease."
Hanzlicek said he is aware of at least two purebred operations that sold breeding bulls this past spring that had hairy heel warts. This led him to believe that hairy heel warts are going to become more of a concern in the cow/calf sector.
He said some feedlot veterinarians have reported that the condition is becoming a problem in the feedyard, which is more understandable. Unlike foot rot, hairy heel warts are extremely contagious.
Herds reporting a high occurrence of hairy heel warts are typically housed in wet environments, Hanzlicek said, adding that most of the diagnostic lab's calls about the issue have been from producers who calve in muddy lots. Importing replacement animals has been associated with hairy heel wart problems, but the most likely cause is poor sanitation practices during hoof trimming.
Contrary to its common name, the infection is not a "wart," which is caused by a virus. While Hanzlicek said experts believe bacteria called Treponema cause the infection, attempts to cause hairy heel warts by exposing animals to the bacteria have been unsuccessful.
The clinical appearance of lameness in the animal is similar to foot rot, he said. Hairy heel warts are circular red to reddish-gray sores on the back of the foot and usually the back feet, right above where the hoof attaches to the skin. Distinguishing between foot rot and hairy heel warts is about the placement of the lesions, Hanzlicek said.
"Foot rot's going to have a crack between the toes; it usually starts at the front of the foot," he said. "Hairy heel warts usually start at the back of the foot, just above where the hoof wall attaches to the skin below the dewclaws."
Hanzlicek warned producers that although lameness might not appear severe, applying pressure to the affected area can trigger a dangerous response from the animal. Producers and veterinarians should be careful when they're examining animals they think have hairy heel warts.
Treating hairy heel warts is harder and less effective than treating foot rot, Hanzlicek said. Rather than an injectable antibiotic, a topical antibiotic seems to be most effective for treating hairy heel warts.
"We're talking about spraying oxytetracycline or a couple of other products on the lesion," he said. "The downside is it needs to be done every day for multiple days."
Hanzlicek said hairy heel warts can be cleared up, but they might not be gone for good.
"After the first treatment, we know that a pretty good percentage of those animals we treat for the first five days may (have a recurrence of) the disease within another couple of weeks, and we're going to have to retreat them," he said. "If I were a producer and I had any idea it was hairy heel warts, I would call my veterinarian and have them confirm the diagnosis."
In the rolling Plains, there are many advantages to using triticale as forage versus wheat or oats, according to Jason Baker, Texas A&M AgriLife Research senior research associate in Amarillo, Texas, who has been conducting trials since 2002.
Triticale is a cross between wheat and rye, and while it was first developed in the late 1800s, the first commercial releases were not available until the 1960s, Baker explained. Triticale grows taller and remains green longer than wheat.
"We've been working several years here to make better varieties for the rolling Plains," he said during a recent field day near Chillicothe, Texas. "We don't see triticale competing for the wheat acres. It's really a complement to dual-purpose wheat. We are trying to use the triticale more for grazing and not put as much pressure on our wheat, allowing us to use the wheat more for grain and the triticale for forage.
"Anyone who grazes wheat or uses wheat for hay might want to at least have some triticale in their program," Baker added. "You can plant the triticale earlier and turn cattle in and save the wheat for grain later on. If you have a lot of growth, you can graze the wheat some, but use the triticale as your main focus for grazing."
Working with about 20 experimental lines and 100 commercially available triticale lines in breeding trials at Vernon, Texas, Baker said he also has compiled eight years of forage yield data comparing triticale, wheat, oats and barley.
The most recent three-year average resulted in the triticale varieties yielding 2.09-2.11 tons of dry matter per acre, compared to 1.69-1.93 tons per acre for wheat, 1.61-1.79 tons for oats and 1.54-2.01 tons for barley.
In 2014, the triticale — after three clippings — yielded considerably better under drought and late freeze conditions, he said. The triticale yields were 1.92-2.00 tons per acre, compared to 1.26-1.58 tons per acre for wheat, 0.88-1.17 tons for oats and 1.13-1.44 tons for barley.
"Triticale tops that test here in the rolling Plains," Baker said. "Our breeding plots have oats and wheat planted next to the triticale, and you can look at the difference: Oats had a lot of freeze damage. The wheat is shorter and just produces less forage."
Baker said the two Texas A&M AgriLife varieties in the forage trial are TAMcale 6331 and TAMcale 5019, "but if you took any good commercial triticale variety, you will get the same results for grazing, hay or silage. They produce a much greater quantity."
He added, "Many triticale varieties have disease and insect resistance that wheat and oats don't have, allowing us to plant a little earlier in the year. We can get cattle on sooner by taking advantage of some of the late summer rains that we might get (in order to) get it in the ground and get a good stand."
In addition to the earlier stand in the fall, Baker said triticale offers an additional two to three weeks of grazing time in the spring.