Taking the precise step with good foot bathtub administration
Digital dermatitis (DD) or hairy heel warts are the most common cause of lameness in dairy cows. According to the University of Wisconsin School of Veterinary Medicine, an estimated 70 percent of U.S. dairy herds have DD and 95 percent of herds with more than 500 cows have DD.
Foot baths are the most common management tool used to control digital dermatitis DD on dairy farms. Proper use of the foot bath makes DD management more effective and saves money by reducing the amount of solution used.
Foot baths are used to disinfect hooves and prevent DD, not for therapy or treatment. Proper use of the hoof bath will keep infected cows in a non-contagious state and prevent new infections in the herd. Once a cow has DD it cannot be cured, only managed.
It is recommended to identify open lesions and treat them topically before sending the cow through a foot bath. Ask your veterinarian about topical treatment options. The effectiveness of footbaths in preventing infectious lesions depends on several factors including the footbath solution, the frequency of changing solutions, footbath dimensions, footbath placement, and animal hygiene.
Foot baths should be at least 10 feet long so that each cow steps into the tub twice with each hoof. The depth of the solution should be kept at least 10 cm so that the dewclaws are submerged when the cow passes.
The concentration of the solution should remain at the recommended percentage as per the product label. Replacing or changing the hoof bath solution depends on the cows’ hoof and leg hygiene.
According to the University of Wisconsin School of Veterinary Medicine, the solution should be changed after 150 to 350 cows have passed the foot bath. When cows have cleaner feet and legs, the solution can be changed after 300 to 350 cows have passed the foot bath. If cows have dirty hooves and legs, the solution should be changed more often. It is important that you monitor your individual farm to determine how often it is best to change the solution for your herd.
The foot bath solution should be kept at a pH of 3.5 to 5.5. Making the solution too acidic or too alkaline will not improve the results of DD management. The skin has a normal pH of 4 to 5.5, so maintaining the pH at normal skin levels will help maintain healthy skin condition and improve treatment outcomes.
It is important to maintain a comfortable pH level for cows. A mindset that low pH (less than 3) and acidic pH create a hostile environment for bacteria to grow. Too acidic a solution will be painful to a cow with an active lesion or open wound on the foot.
The normal pH of a lemon is between two and three. You don’t want to squeeze lemon juice over an open wound on your hand, do you? Don’t expect a cow to have to do the same thing.
Treatment solutions vary by facility, but copper sulfate solutions are the most common. The antibacterial properties of copper sulfate help keep the hoof clean, and it also has a hardening effect on the claw horn.
The popularity of copper sulfate footbaths can be attributed to both its relatively low cost per animal treated and the general perception among farmers that it is effective in fighting infectious lesions. Research has shown that using copper sulfate foot baths reduces both the incidence and severity of hoof lesions.
However, some data suggests that organic matter quickly neutralizes copper sulfate, making dirty footbaths less effective than clean ones. A copper sulfate concentration of two to five percent is recommended.
Formalin foot baths are also popular, but some have reservations as it is a known carcinogen. Like copper sulfate, it kills bacteria, hardens the claw horn, and is inexpensive. Bacteria do not develop resistance and formalin eventually breaks down into water and carbon dioxide.
Research has shown that formalin footbaths reduce the incidence and severity of claw lesions and can maintain its antibacterial properties for up to 330 animal corridors. The typical formalin treatment concentration is three to five percent. The use of formalin requires additional precautions. Therefore, read the safety label carefully and understand it.
Visit the University of Wisconsin School of Veterinary Medicine Dairyland Initiative website to find the Foot Bath Dose Calculator at https://bit.ly/3fpURiV.
The frequency of treatment varies depending on the herd. If a DD outbreak occurs, treat the flock three times a week. Monitor treatment results and increase treatment to four to five times a week if DD does not improve.
Foot bath maintenance treatments can be done on a schedule such as Monday-Tuesday-Wednesday or Monday-Wednesday-Friday. Design your foot bath so that the cows can bypass the treatment if necessary. On treatment-free days, a simple chlorine or soap bath can be used to keep feet clean.
Remember that DD treatment is not a one-size-fits-all practice. Effective foot bath management requires the proper use of solution and foot bath facilities while monitoring leg hygiene and foot health.
Aerica Bjurstrom is the agricultural officer for the UW-Madison Division of Extension Kewaunee County