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Flashcards in Farm Animal Lameness 1 Deck (30):

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