Hoof Pathology I- Ruminants Flashcards
What are 6 problems that are associated with lameness?
- Welfare
- Increased Calviing interval
- Public Perception
- Reduced Milk yields
- Labour costs
- Increased culling
What are the 4 success factors for healthy feet?
- Low infection pressure
- Good hoof shape and horn quality
- Early detection and prompt, effective treatment of lame cows
- Low forces on the feet and good cow comfort
What are the two non-infectious causes of cattle lameness?
- Sole bruising/ Ulcers
- White line disease
What is the non-infectious cause of sheep lameness?
White line disease
What are the three infectious causes of cattle lameness?
- Digital dermatitis
- Interdigital necrobacillosis
- Heel Horn erosion
What are the three infectious causes of sheep lameness
- Scald
- Foot rot
- Contagious ovine digital dermatitis
How do sole ulcers occur?
- Pressure from P3 onto the corium
- Most severe at the flexor tuberosity on P3
- Inflammation -> Oedema -> Haemorrhage at the corium
- Disruption of horn growth
- Results in an area of exposed dermis
What are the underlying causes of sole ulcers?
- Standing times
- Horn shape
- Digital cushion
- Suspensory apparatus
- Coriosis
What three things can cause damage to the white line?
- Haemorrhage
- Foreign bodies
- Poor hoof conformation and horn quality
What are the underlying causes of white line disease?
- Shearing forces
- Haemorrhage
- Hoof conformation
- White line health
- Stretching of collagen fibres
What causes collagen fibre stretching?
Relaxin and MMP release
What do treponema species cause?
- Polymicrobial infections
- Highly contagious
- they are a superficial, erosive infection of the skin
What are the underlying causes of bovine digital dermatitis?
- Poor foot hygeine
- Poor biosecurity
- Lack of preventative treatment
- Poor lesion detection
What are the two steps to interdigital necrobacillus?
- Damage to the interdigital skin ascending to deep soft tissue
- Bacterial infection that starts in the interdigital space
What can cause damage to the interdigital skin?
- Trauma
- Prolonged standing in deep mud/ slurry/ water
What two bacteria go on to cause interdigital necrobacillus?
- Fusobacterium necrophorum
- Trueperella pyogenes
What is scald?
superficial infection of the interdigital skin
What bacterium causes scald?
Fusobacterium necrophorum
What is scald a precurser to?
It is a precurser to foot rot
When is scald common?
Scald is common in grass in wet conditions
What is foot rot a sequel to?
Sequel to scald
What is the pathogenesis of foot rot?
Erosion of the axial hoof wall, with deep infection of digital tissues and underrunning of the sole
What bacteria causes foot rot?
Dichelobacter nodosus and fusobacterium necrophorum
What disease is extremely painful and foul smelling?
Foot rot
What three bacteria cause contagious ovine digital dermatitis?
Mixed infection
1. Treponema spp.
2. F.necrophorum
3. D.nodosus
How does contagious ovine digital dermatitis occur?
- Primary lesion at the coronary band
- under running of the hoof wall
- hoof wall detachment
- sloughing of the hoof capsule
What is the main pathology of foot rot?
Separation at the skin/ horn junction -> spreads across the axial wall, sole and abaxial wall -> sloughing of the hoof capsule
What is the main pathology of CODD?
Under-running of the hoof wall -> sloughing of the hoof capsule
What is the pathogenesis of toe granulomas?
Disruption of the sole/ wall horn due to over-trimming -> exposure of the corium -> granuloma formation
