Farm Animal Lameness 1 Flashcards
Most common conditions seen by vets
> deep digital sepsis > Toe necrosis - Trypaneames (?) (infect back of heel normally) > Interdigital hyperplasia - requires surgical removal > wall ulcer *salvage procedures*
Most common problems seen by farmers and foot trimmers
> sole ulcer (always same place, axial to midline on heel)
- develops ino deep digital dermatitis
white line dz (abaxial white line, commonly heel but can be toe)
- develops into a wall ulcer
digital dermatitis (trepanemes (?))
- interdigital hyperplasia
foul
Which foot dz has a genetic componenet?
- inerdigital hyperplasia
How much can foot problems cost to tx?
- sole ulcer deep dgital derm $524
- white line wall ulcer $330
- interdigitcal hypereplasia $75
What willl deeep digital derm lead to?
Bony changes and ankylosis
- will never walk norally again
Pertinent hx q for lameness in cattle?
> lactation - heifer? better prog > how long calved - early lactation can do more extreme tx? - late lactation dry off early and tx? > previous or other problems > how long has she been lame? - boney change > tx so far > pregnant? milking well? cull list? - decide best tx sx or pts
What does a score 0 lameness look like?
- walks even weight bearing and rhythm on all 4 feet, flat back
- long fluid strides
- see video on lect
What does a score 1 lameness look like?
- steps uneven (rhythm or weight bearing)
- strides shortened
- affected limbs not immediately identifiable
What does a score 2 lameness look like?
- uneven weight bearing on limb immediately identifiable
+- shortened stride - arch to the centre of the back
What does a score 3 lameness look like?
- unabl to walk as fast as brisk human pace
- cannot keep up with herd
- signs of score 2
Where is the majority of lameness seen in dairy cattle?
- 92% hindlimbs
- 65% lateral claw
- 12% not foot related
OUtline foot eamination
- nb: may not be able to stand for long if sore on all feet once one picked up
- hoof testers(subtle reacions - don’t jump like horses)
- press heel
- feel heat
> bulls that dont fit in crushes - sedate? big crush?
What foot trimming procedure is used most commonly? NOT FINISHED
Dutch 5 step (covered in prac) 1- create a foot angle of 52* > trim toe to correct length, start inner hind or outer fore > 7.5-8cm from coronary band > 2- create balance between claws 3- transfer weight from sole to wall, toe and heel 4- remove weight from painful claw 5- remove loose or sharp claw
WHat signs may be picked up on hoof exam
- softening at heel or coronary band
- smell
- swelling above coronary band/in heel
- redness skin (beware haemorrhage in horrn is approx 2months historic)
What must be decided if red cherry like lump protruding from uncomplicated sole ulcer seen? Tx?
- granuation tissue (not innervated) > chop off
- corioin (innervated) > dont chop off
Tx sole ulcers. prog?
- tx early
- 5 step dutch
- ABx
- NSAIDs (ketofen, 3d)
- nursing and clean yard
- promote wound healing - nothing that cauterises [CuS commonly used by farmers not good]
- prog: ok but will recur next lactation, v fertility and lifespan, milk should recover in ~ weeks but lower on average than herd
What do farmers think causes sole ulcers? What actually causes it?
- stone in hoof or acidosis or laminitis / failure suspensory (v controversial)
> acidosis does not DIRECTLY cause claw horn lesions
> environmental conditions most likely cause
> BCS (and loss in early lactation) and claw horn growth rates may be important in sole ulcer pathogenesis
> Biotin [ ] may improve claw horn quality and v white line lesions
> ^ dry matter diet will v claw horn lesions (likely d/t drier dung -> bette environmental conditiions)
Outline pathogenesis of sole ulcers NOT KNOWN BY FARMERS/VETS, REMEMEBER THIS
- originate under DDFT insertion on P3
- preceded by change in structural integrity of laminae aound calving (but not laminitis) hormonally mediated?
- P3 moves away from claw horn capsule
- under P3 digital cushion thickness affeced by BCS (if lost -> become thinner)
- predisposes trauma through the sole
- change in shape of claw
- ^ risk of trauma and overload on thin digital cushion [viscious cycle]
- white line dz can also predispose
- treponemes become established in wound
Potential herd interventions for solar ulcers
- put freshly calved heifers on “comfort” straw yard for 16 weeks
- effective!
2 potential tx of white line disease?
Open up just enough to drain?
- beware treponemes tracking up wound to corion
OR open up whole wall to expose corion
- with block on other side
> drain pus
> cut away dead horn (can be done 2 weeks later)
> sharp knife!!
> apply a block
> NSAIDs to v swelling
> Abx oxytet LIC
> good prognosis UNLESS wall ulcer infected with treponemes
What are the stages of white line disease?
> dz horn affecting junction between sole and wall, including
- bruising (hameorrhage)
- separation (fissure)
- abscessation
- ulceration (recorded separately d/t severe and chronic pain associated with it)
Pathogenesis of white line disease?
- poor horn quality?
- wet conditions?
- stones?
- P3 descent?
- v BCS
- thin soles?
- turns?
- lack of BIOTIN
> biotin supplementation is portective
Effective interventions for white line dz?
- biotin (also ^ milk yield)
- feeding hay
- dry diets
Outline digital dermatitis scoring system
M1: ulcerative 2cm
M3: regressing
M4: hyperkeratotic (‘hairy wart’ most common presentation, chronic carriers)
M4: reactivating
DD Tx? Different severitys of lesion?
M1: clean, dry, topical oxytet (3 consequtive days)
M2: = above but debride with paper toel/gauze and consider bandaging with ABx (make bandage loose - left on too long causes more problems than its worth!)
M4: clean, debride and debulk (Local anaesthesia) bandage with Abx
Effeective interventions for DD?
> footbath (erythromycin, formalin[most common], copperr sulphate, peracetic acid)
- even best tx not efective if used alone and walking around in slurry all day
biosecurity and slurry management
What is the significance of lameness in production animals?
- pain, suffereing and distress (welfare)
- 5 freedoms compomised
- consumer concern
- production disease - (^ incidence with ^ productiviy) necessitates management
- economic
What is foul in the foot?
- acute bacterial infection of subcut tissue
- symmetrical swelling, separation of claws and interdigital skin necrosis -> pungent odour
- often d/t FB or sand
> superfoul = severe peracute form, mixed bacterial infection`
Tx foul in the foot?
- clean/debride interdigitcal space
- disinfect
- LIC injectable ABx
What is corkscrew claw?
- bony swelling deep to abaxial coronary band is diagnostic
- not to be confused with gross claw overgrowth
- reshape foot as best as possible
