Lameness: Infectious Causes Flashcards
What are the most prevalent causes of infectious lameness?
- Digital dermatitis
- Intergdigital phlegmon (foul)
- Interdigital dermatitis
- Heel horn erosion
- What are the different names for digital dermatitis?
- What family of bacteria cause it?
- How does it appear?
- Mortellaro disease, hairy heel warts, strawberry foot
- Strains of spirochete bacteria: treponema denticola, medium, phagedenis
- Painful, reddened area usually just above interdigital cleft, between heel bulbs, erected hair sometimes around the lesion
What is required for digital dermatitis infection?
- Skin damage- treponemes/lesion material not enough
- Have been identified in hair follicles and sebaceous glands- possible entry
- Possibly gut microbiome?
What is the role of foot skin microbiome in DD?
- Changes in the foot skin microbiota profiled before presence of dectable DD lesions
What are the possible risk factors to DD?
- Housing hygiene
- Foot trimming practices
- Biosecurity
- Stocking density
- Parity and repeatability
- Genetics
How can housing/hygiene increase DD?
How can foot trimming practices affect DD?
Housing/Hygiene
* Increased exposure to slurry/wet/wet concrete increases risk
* Grooved floors?
* Access to pasture may help
Foot trimming
* Increased incidence of BDD with trimmer with lack of washing
* BDD treponemes identified post-trimming
- How could biosecurity increased BDD?
- How can stocking density contribute to DD?
- How does parity affect DD?
- Purchasing heifers from other farms- risk factor
- Overcrowding will lead to increased standing times. Combined with poor hygiene/problem
- 1st lactation animals have an increased risk, once infected likely to stay infected (chronic/repeatable)
How can DD be controlled?
- Identify risk factors and improve conditions
- Early treatment of clinical cases
- Genetic selection
- Footbathing
When does DD need to be identified?
- Mobility scoring isn’t sensitive enough
- Parlour scoring is required
What can be used to footbath DD cases?
Are they useful?
- Copper sulphate
- Formalin
- Zink sulphate
- Commercial products- big claims
- ABs- bad use of ABs- not licensed therefore 5-7 days milk withhold
- Need to be changed regularly
- Contact time
Most use formalin and CuSO4- formalin Carcinogenic
How is DD treated?
- Animal in crush
- Clean and dry lesion very well
- Apply topical ABs
- Apply other products- salicylic acid
- Wrap- no point if going to dirty housing
- NSAIDs- consider
There is no licensed whole herd treatment for DD
What is the ‘blitz’ approach?
- Screening whole herd for DD lesions
- Simultaneous treatment of all active and recurring lesions
- Imroved hygiene and footbathing protocols
Does DD complicate claw horn disruption lesions?
- Various oppertunistic pathogens can complicate lesions
- Association with non-healing
- What are the different names for foul in the foot?
- What bacteria mainly causes it?
- How does is present?
- Foot rot, interdigital phlegmon, interdigital nercobacilosis, infectious pododermatitis
- Fusobacterium necrophorum
- Swelling above claws/ characteristic odour- very painful
How is foul in the foot treated?
- Get animal in a crush
- Clean lesion really well
- Remove necrotic tissue
- Systemic ABs
ABs- ceftiofur works well (avoid), oxytet, penstrep can work
What could interdigital dermatitis be?
What bacteria may cause it?
- Milder infection of the interdigital skin
- Different manifestation of DD
Dichelobacter nodosus, spirochetes have been isolated
