Foot baths control infectious disease

Sherry A. Bunting, Ag Projects Writer, Agriculture Writing & Photography Services for Progressive Dairyman

Foot rot (interdigital necrobacillosis) and hairy heel warts (digital dermatitis) are contagious diseases which are promoted by environmental conditions and triggered by stress. They are a leading cause of lameness in dairy cattle today.

Foot rot is caused by bacteria that live in wet, muddy conditions. They enter through cracks in the hoof, physical injury or hoof walls softened by prolonged exposure to mud and manure. These bacteria commonly attack the skin between the rear claws, causing the animal to “paddle” from foot to foot in discomfort.

Heel warts are a widespread and more persistent problem. Their exact cause is still unknown but believed to be an invasion by spirochete bacteria, which colonize the outer layers of the hoof and then invade the living tissue. Lesions typically occur just above the heel on the rear feet, first appearing as a reddened area, which becomes extremely painful to the animal. In freestalls, infected cattle may be reluctant to move once they’ve reclined, leading to slug feeding, acidosis and complications of laminitis.

Heel warts are very contagious and easily spread among animals, particularly in overcrowded situations and environments with poor drainage, accumulation of manure and urine on floors, rough flooring or dirty, wet, uncomfortable bedding areas.

Constant exposure and the fact that the organism cannot be permanently killed, make this condition difficult to manage. Even when there are no visible signs, it can still be present. When a specific stress or environmental condition triggers the disease, it can spread rapidly. Monitoring (early detection), maintenance (by a qualified hoof trimmer) and management (animal environment and foot baths) are critical to improve recovery, reduce suffering and minimize economic losses.

“Foot baths are extremely effective if they are used and managed properly,” says Paul Neer, former president of the Hoof Trimmers Association. “Infectious diseases like heel warts can be eliminated pretty quickly if producers are faithful about running their foot baths.”

“In one customer’s herd of 2,000 cows, heel warts are simply not an issue because they run their foot bath treatments during two out of three milking shifts daily,” Neer explains. In this example herd, two copper sulfate-treated foot baths are used, preceded by a cleansing foot bath containing only water.

Frequency of use will depend on herd size and facility management. Each time a new animal enters the milking herd, a foot bath for the entire herd should be used at least once daily for at least one month. This is one reason why large herd managers will run foot baths more than once a day on a continuing basis.

Neer gives these management tips for an effective foot bath:

•Use it faithfully
The most important thing is to use the foot bath regularly. Using it once in awhile is not effective.

•Keep it clean
A dirty foot bath provides no service and can create more problems. Keep an eye on the bath and use good judgment to decide when to change it (approximately every 150 to 250 cows). Frequency will depend on cleanliness of environment, size of herd and whether a pre-bath for cleansing is used or a second treated bath is provided. Don’t rely on numbers. The water should still be blue-green, not brown when it is changed.

•Single-file, no-return access
Foot baths should be set up on a level surface where cows must walk single-file, with no-return access. This ensures the cattle will use the foot bath and prevent them from soiling or attempting to drink from it.

•Hygiene and bedding
Good stall hygiene and bedding management is a paramount issue. Aside from overcrowding, Neer believes this is the number one issue contributing to foot problems and premature death. Sufficient bedding is needed even with cow beds or mattresses. For fewer foot health problems and increased foot bath effectiveness, keep stall bedding, alleyways and outdoor lots clean and dry.

Excessive buildup of wet, soiled bedding on the foot, interferes with penetration of foot bath treatments. This is especially true of wet shredded-paper bedding, which can form a tough, paper machelike “cast.”

•Topical antibiotics
At the first sign of an active heel wart, direct-treat the infected area. Several topical applications of tetracycline using a spray bottle or syringe are effective. Spraying all feet with a topical antibiotic solution is also effective and economical as a herd control alternative to medicated foot baths. Sore heels with obvious lesions should be cleansed, evaluated and treated by a professional trimmer or veterinarian.

•Don’t forget dry cows and heifers
These animals also benefit from foot bath treatments. In a 100-cow herd, for example, a foot bath treatment for heifers and dry cows should be used once or twice every 10 days to two weeks.

Large-herd managers will run daily foot baths for dry cows and heifers. Neer advises producers to check dry cows and heifers daily for foot health and early signs of lameness. “Don’t forget these animals,” he stresses. “I have seen fresh cows and heifers with bad warts and serious lameness issues, which did not happen overnight.” First-calf heifers are particularly susceptible to foot problems as they are introduced to new housing, routines and dominant cows. To limit the impact of stress on performance and health, ensure good foot health and body condition, before calving.

“A well-managed foot bath is an effective prevention and control tool, but not all products are created equal,” says Neer. “We continually see new products on the market, but they must be practical and economical, and they have to work.” Be aware of handling characteristics, proper dilutions and intended use of various foot bath agents for safety and effectiveness. PD

References omitted but are available upon request.

—Reprinted with permission from May 2005 Focus of the Month, published by Agri-Basics, Inc.