Infectious lameness causing foot lesions 1, 2, 3

Question 1

What are the 4 main causes of infectious foot disease in cattle?

Answer 1

Digital dermatitis
Interdigital phlegmon = foul in the foot
Interdigital dermatitis
Heel horn erosion

Question 2

Mortellaro disease, hairy heel warts, strawberry foot are all examples of?

Answer 2

Digital dermatitis

Question 3

What is the aetiological cause of digital dermatitis?

Answer 3

Strains of spirochete bacteria; Treponema spp.

Question 4

How does digital dermatitis present?

Answer 4

• Painful, reddened area usually just above interdigital cleft, between heel bulbs
• Erected hair around the lesion (not always)

Question 5

Describe how to grade digital dermatitis lesions

Answer 5

M0 = healthy skin, no signs of digital dermatitis
M1 = early stages of disease, less than 2cm diameter, red/grey epithelial defect
M2 = acute, active ulceration, greater than 2cm diameter
M3 = healing stage within 2 days of topical treatment, scab on top of a recently scabbed lesion
M4 = chronic proliferating or dyskeratotic lesion
M4 1 = chronic recurring lesion with subacute components

Question 6

Describe the aetiopathogenesis of digital dermatitis

Answer 6

Skin damage important. Treponemes/ lesion material alone not enough
Treponemes have been identified in hair follicles and sebaceous glands, suggesting a potential route of entry

Question 7

Describe the risk factors of digital dermatitis

Answer 7

• Slurry/ wet conditions/ wet concrete
• Grooved flooring (wide gaps between grooves may help)
• No access to pasture
• Biosecurity: purchasing heifers from other farms
• Infected cows spreading infection
• Overcrowding -> increased standing times
• Poor hygiene
• Lack of washing of hoof trimming equipment between cows
• 1st lactation animals
• Recurrence common

Question 8

Describe how digital dermatitis can be controlled

Answer 8

• Identify risk factors and improve conditions
• Early treatment of clinical cases
• Genetic selection
• Foot bathing

Question 9

Name 3 chemicals used in foot baths for digital dermatitis

Answer 9

Copper sulphate
Formalin
Zinc sulphate

Question 10

What is the issue with formalin footbaths?

Answer 10

Carcinogenic

Question 11

How is digital dermatitis treated?

Answer 11

Get animal in a crush
Clean and dry lesion really well
Apply topical antibiotic treatment
Other products (salicylic acid) ?
To wrap or not to wrap?
NSAIDs?

Question 12

What is the causative agent of foul in the foot?

Answer 12

Fusobacterium necrophorum

Question 13

Describe the presentation of a cow with foul in the foot

Answer 13

Acute onset!
Swelling above the claws/ characteristic odour
Generalised swelling of the whole foot
Usually very painful!!

Question 14

How is foul in the foot treated?

Answer 14

Get animal in a crush
Clean lesion really well
Remove necrotic tissue
Systemic use of antibiotics

Question 15

Describe the features of interdigital dermatitis

Answer 15

Milder infection of the interdigital skin
Dichelobacter nodosus?
Can spread across the heels (heel horn erosion)
Could it be just a different manifestation of DD