What is it?
- Infectious hoof diseases are caused by bacterial infections of the skin around the hoof.
- There are 3 main lesions:
- Digital Dermatitis (aka Heel Warts)
- Foot Rot (Interdigital Necrobacillosis or Phlegmon)
- Heel Horn Erosion
Digital Dermatitis (D)
What causes it?
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- Digital Dermatitis is a multifactorial disease with a strong bacterial component.
- Amongst the bacteria involved, a Gram-negative spirochete bacteria called Treponema spp appear to be necessary for the disease to occur.
- There is a genetic susceptibility to chronic infection which appears common in the Holstein breed
Digital Dermatitis Lesion Classification
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- (from Dopfer et al. 1997)
How do we treat it?
- We have to identify cows with active stages of digital dermatitis (M2 and M4.1) as soon as possible by weekly active surveillance of cows in the parlor or at the feed bunk before they become lame.
- Active lesions need to be treated with a topical antibacterial.
- Efficacy of treatment of chronic stages of the lesion (M4) is poor.
A topical antibacterial is applied with or without a light wrap. Use of ~2000 mg tetracycline powder mixed with 6ml propylene glycol is effective but use is EXTRA-LABEL and should be administered under guidance from the Veterinarian of Record (VOR). A milk withhold period may be required.
How do we prevent it?
Prevention of digital dermatitis is dependent upon:
- Breeding heifers that are resistant to chronic disease.
- Using in-feed trace mineral supplements to enhance the resistance of the epidermis to infection in heifers.
- Limit the spread by treating active lesions as soon as they occur.
- Routine use of an antibacterial footbath.
- Improve foot hygiene
Footbath Best Practices
- Bath as infrequently as possible to reduce transitions from chronic to acute DD lesions
- Use a well designed footbath to optimize transfer of antibacterial to feet
- Locate a mixing station adjacent to the footbath for safe handling of chemicals
- Start a regime once a day for 4 days per week and adapt based on outcome
- Use an antibacterial with proven efficacy that DOES NOT DAMAGE THE SKIN DEFENCE – maintain pH>3.0
- Use the bath as long as it is effective ~ 100-300 cow passes
- Don’t forget the dry cows and heifers!
- Footbath Dose Calculator (.xlsx)
