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Flashcards in Farm animal MSK disease 3 Deck (100)
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Discuss the prognosis for vertical fissures in cattle

- Generally good
- Some can be difficult to treat, require multiple trims before wall normal
- If periople permanently damaged, leading to continued production of defective wall, long term prognosis is poor


Outline the aetiology of horizontal fissures in cattle

- Interruption of wall horn production at coronary band
- Any severe toxic condition e.g. mastitis, metritis, acute acidosis
- Will be complete circumferential fissure around all 8 claws


Outline the clinical signs and presentation of horizontal fissures in cattle

- Often asymptomatic unless fissure and underlying laminae infected or granuloma produced
- if get production of thimbles of wall and sole on all claws, movement of this relative to rest of wall results in lameness, infection and granulomas


Outline the treatment of horizontal fissures in cattle

- If infection present, open crack and drain abscess
- Resect granulation tissue
- Often all claws affected so no blocks


Discuss the prognosis for horizontal fissures in cattle

- prognosis varies depending on severity of disease
- Sometimes thimbles grow out and are shed asymptomatically, other times may have to cull affected animal


Explain the difference between horizontal fissures and hardship lines in cattle

- Hardship lines = incomplete disruption of horn production, producing thin wall


Discuss the aetiology of fracture of the distal phalanx in cattle

- Uncommon
- Trauma during bulling (slipping off cows) or slipping off steps
- Flouride poisoning (herd "outbreaks")


Describe the clinical signs of fracture of the distal phalanx in cattle

- Acute onset severe lameness, no other obvious clinical signs
- If medial claw of front feet affected, animals stand with forelimbs crossed


What is required for definitive diagnosis of distal phalanx fracture in cattle?



Discuss the treatment and prognosis for fracture of the distal phalanx in cattle

- Distal phalanx well splinted by hoof capsule
- Only need to apply block to unaffected claw
- Prognosis good unless complicating factors e.g. fluoride poisoning


Outline the aetiology of interdigital skin hyperplasia in cattle

- Chronic irritation of interdigital area e.g. chronic infection or impaction
- Foul in the foot may predispose to condition later in llife
- Hereditary component suggested


Outline the clinical signs of interdigital hyperplasia in cattle

- Skin hyperplasia often asymptomatic, noted during routine foot trimming or inspection
- Lame if overgrowth becomes infected or pinched during movement


Outline the treatment and prognosis for interdigital skin hyperplasia in cattle

- If infected, treating infection treats lameness
- If pinching, dish out horn from interdigital area
- In severe cases or where corrective trimming ineffective, surgically remove hyperplastic skin under local or IVRA
- Good prognosis


How may interdigital skin hyperplasia be prevented

Ensure underfoot conditions are optimal during the winter housing period


Outline the aetiology of suprascapular paralysis in cattle

- C6 and C7 outflow innervates supraspinatus and infraspinatus
- Usually damaged by trauma to prescapular or scapular area


What would the following clinical signs be most suggestive of in a cow?
Thoracic limb advanced normally but abducts when weight bearing, shortened stride, atrophy of infra and supraspinatus

Suprascapular paralysis (NB atrophy can be complete)


Outline the aetiology of radial paralysis in the cow

- Excessive traction on limb e.g. calving, trauma to scapulohumeral area, prolonged recumbency
- C7, 8 and T1 give motor innervation to carpus and digit extensors, and sensation to lateral aspect of limb


What would the following signs be most suggestive of in a cow?
Forelimb held in flexion with elbow dropped, evidence of scuffing on the dorsal hoof wall

Radial paralysis


What may be seen if only the distal portion of the radial nerve is damaged in a cow?

Innervation to elbow normal, but carpus and fetlock are held in flexion


Describe the aetiology of brachial plexus paralysis in cattle

- Excessive traction of limb e.g. calving, traumatic abduction, prolonged lateral recumbency
- C5 to T2 outflow = radial, median and ulnar nerves


List your differentials for the following clinical signs in a cow:
- Flaccid left forelimb
- Non-weight bearing
- Hoof dragging on the foor

- Brachial plexus paralysis (most likely if no other signs)
- Scapulohumeral luxation
- Fracture (e.g. humeral)


Describe the aetiology of obturator paralysis in a cow

- Damaged during dystocia usually, often due to foetal oversize
- L4, 5 and 6 outflow make up obturator nerve, innervates adductor muscles of HL


Describe the aetiology of femoral paralysis in a cow

- Usually damaged in calves during dystocia caused by hiplock
- Calf's limbhyperextended during traction
- Femoral nerve composed of outflow from L4, 5 and 6, innervates iliopsoas and quads


What are the following signs indicative of in a calf?
- HL virtually non-weight bearing
- Stifle cannot be extended
- Limb hangs in flexed position with digits resting on floor

Femoral nerve paralysis


Describe the aetiology of sciatic paralysis in cattle

- Commonly injured during dystocia caused by foetal oversize
- occasionally by prolonged periods of lateral recumbency and iatrogenically through IM injections into HL


What are the following signs indicative of in a cow?
- HL non-weight bearing
- Stifle and hock held in extension and distal joints of foot are flexed
- Foot is knuckled over
- Limb is dragged along by extension of the hip

Sciatic paralysis


Describe the aetiology of tibial paralysis in the cow

- Damage is rare, usually caused by extensive trauma to gastrocnemius area
- Supplies motor innervation to extensors of hock and flexors of digit


Describe the clinical signs of tibial paralysis in the cow

- Weight bearing shifted onto heels
- Animal walks with jerky motion


Describe the aetiology of peroneal paralysis in the cow

Damaged during periods of prolonged recumbency or sudden falls that damage the lateral aspect of the stifle joint


Describe the clinical signs of peroneal paralysis in the cow

Fetlock flexed (knuckled over) and hock extended, weight bearing but tends to stumble


Outline the general treatment for peripheral nerve paralysis in cattle

- Relies on keeping animal comfortable e.g. deep soft bedding, non-slip surfaces
- Anti-inflammatory drugs to reduce swelling
- Supportive dressings in some cases


Discuss the prognosis for peripheral nerve damage in cattle

- Bruising or swelling of the nerve usually respond well to conservative management
- Prognosis for complete rupture very poor


Discuss the aetiology of white muscle disease in cattle

Selenium and vitamine E deficiency, and high levels of poly unsaturated fatty acids in the diet


Discuss the clinical signs of white muscle disease in cattle

- Muscular dystrophy in growing animals
- Peracute: sudden death
- Acute: lateral recumbency, dull, respiratory disease, tachycardia, dead within 24h
- Subacute: stand and walk stiffly, reluctant to move, weakness, eat normally
- Chronic: ill thrift, poor weight gain, lower survival rate
- Retained cleansing, metritis, cystic ovarian disease
- Heinz body anaemia in growing calves


Discuss the clinical signs of white muscle disease in sheep

- Muscular dystrophy in lambs
- lambs born weak/die within a few days
- Acute: 0-4 months, stand and walk stiffly, weak, ddx joint ill
- Chronic: ill thrift, poor weight gains, lower survival rate
- High embryonic mortality, infertility in ewes
- Heinz body anaemia in growing lambs


How can white muscle disease be diagnosed in cattle?

- PM: white plaques in myocardium, white striations in skeletal muscle
- Erythrocyte GSHPx
- Serum/plasma CK (elevated)
- Response to supplementation


Discuss the treatment and prevention of white muscle disease in cattle

- Parenteral (SC, IM) injection of SE, usually combined with vit E (e.g. Vitenium), usually re-dose q1-2 weeks, or depot (Deposel)
- Addition to feedstuffs
- Selenium boluses (+Co, Cu often)
- Free access minerals
- Medicated water
- Drenching
- Application of Se salts to soils


Which cattle breeds are predisposed to spastic paresis?

German and dutch Friesians, Aberdeen Angus


Discuss the clinical signs and presentation of spastic paresis in cattle

- Chronic and progressive contraction of gastrocnemius muscle
- 6weeks-6months of age
- Hock nearly straight
- Stiff stilted gait
- Limbs may jerk intermittently at rest


Discuss the treatment of hock cellulitis/bursitis/trauma

- Usually no treatment needed unless infected
- Most lesions resolve over summer months when outside


What is the following presentation typical of in a cow?
Bilateral dropped hocks to floor level

Gastrocnemius rupture (usually occurs at musculotendinous junction and usually bilateral)


Discuss the treatment and prognosis of gastrocnemius rupture in a cow

- NSAIDs e.g. meloxicam
- Close confinement with limbs splinted in extension for number of weeks to allow healing and fibrosis
- Prognosis guarded, unlikely to fully recover, re-rupture may occur


List the NSAIDs licensed for use in cattle in the UK



What are the key risk factors for the development of foot lameness in cattle?

- Standing on hard ground
- Hoof overgrowth
- Periparturient increase in movement of pedal bone
- Loss of fat from digital cushion (weight loss)
- Poor underfoot conditions
- Poor hygiene of foot trimming equipment


How can the risk of foot disease resulting from long periods of standing be mitigated in cattle?

- Promote lying by improving cubicle comfort
- Cubicle training for heifers for post-calving period
- Limit standing time waiting for milking


How can the risk of foot disease resulting from the periparturient increase in pedal bone movement be mitigated in cattle?

Provide periparturient animals with best accommodation to minimise risk


How can the risk of foot disease resulting from weight loss be mitigated in cattle?

- Minimise BCS loss to peak yield
- Identify and treat animals early to limit impacts of disease


How long should cows ideal spend lying down?

12 hours


How many cubicles should be provided to cows?

5-10% more cubicles than cows


Discuss the bedding for cow cubicles

- If uncomfortable leads to hock and hip abrasions, ulcerations
- Should be absorbent, dry and comfortable
- Deep straw: very comfortable but increased risk of mastitis
- Sand: soft when lying, hardens when standing (easier), but abrasive
- Mattress and mats lots of variation, can be good but expensive, make sure cubicles good first


Describe the ideal cow cubicle design

- Must have sufficient lunge zone (~90cm)
- 2.2m long, 1.2m wide


Outline how heifers may be managed pre-calving in order to reduce the incidence of post-calving lameness

- Cubicle training during rearing (at least one month in cubicles before calving)
- Expose to concrete before calving to allow foot to adapt


Outline how a fresh cow group may be managed in order to reduce post-calving lameness

- Separate fresh cow group
- Provide best cubicles at low stocking rate, or v clean straw yard 4-6 weeks after calving


Discuss the importance of diet in the prevention of foot lameness

- Low fibre diet = more sole haemorrhage and sole ulceration
- Minimise BCS loss to peak yield
- Avoid SARA (although not related to claw horn lesions)


What should the ideal cow track allow?

- Rapid flow of cows without chasing
- Comfortable and easy travel
- Minimise damage and risk of lameness
- Keep cows clean
- Reduce loss of pasture due to poaching
- Support some vehicle use if absolutely necessary


What possible substrates should be used for cow tracks?

- Oolitic limestone
- Pine peelings, wood chip, rape straw
- Chalk or sand
- Shellet/soft stone
- Concrete/tarmac kept free of stones ok, ideally with softer covering e.g. quarry belting/cow carpet


What does the addition of biotin (B7) to the diet protect against and which cows are at particular risk?

- White line disease
- Esp. high yielding cows on high concentrate (SARA may reduce B vitamin production)


Discuss the use of footbaths for the prevention of foot lameness in cattle

- 2-7 days/week
- Must keep clean
- 1 litre of foot bath per cow passage


Compare the footbathing solutions that may be used in cattle

- Formalin 2-5% (carcinogenic, hardens feet)
- Copper/zinc sulphate 5%, safer vs formalin, toxic to cows, build up in environment
- 1%peracetic acid
- 1% hypochlorite


Discuss the importance of biosecurity in the prevention of foot lameness in cattle

- Digital dermatitis infectious
- Maintain closed herd where possible
- Care re. fomites e.g. boots, PPE, foot trimming equipment, machinery


Discuss the slurry management in the prevention of foot lameness in cattle-

- Scrape slowly, methodically, as often as possible
- Hand scrape areas not reached mechanically
- repair/improve concrete to prevent pooling of stale slurry
- Automatic scrapes are risk factor for digital dermatitis (waves cover feet)


Describe the clinical signs of scald/strip/interdigital dermatitis in sheep

- Inflammation of skin between claws
- Reddening, hair loss
- White/grey scum


Describe the clinical signs of footrot in sheep

- Smell
- Grey ooze
- Underrunning of horn hoof near to skin between claws
- Underrunning horn anywhere


What pathogens are associated with the development of footrot in sheep?

Dichelobacter nodosus and Fusobacterium necrophorum


Explain the pathogenesis of footrot in sheep

- D nodosus and F necrophorum found in all sheep
- D nododus is the main cause, causes the under-running
- F necrophorum is a commensal that then invades and worsens the condition


Compare interdigital dermatitis and virulent foot rot in sheep

- Same thing, different degrees of disease
- D nodosus higher load in ID than VFR
- F necrophorum is an opportunist that then causes progression to VFR


Discuss the treatment of foot rot in sheep

- Need to treat ID and VFR = lower lameness prevalence
- ID may be more infectious
- Need to treat and separate affected sheep from flock to prevent environmental accumulation


Describe the appearance of contagious ovine digital dermatitis

- Highly invasive, painful lesion starting at coronary band
- Rapid invasion and underrunning of hoof wall
- Horn missing


What pathogens are involves in contagious ovine digital dermatitis?

Spirochaetes/treponemes, also D nodosus


Outline the treatment and management of contagious ovine digital dermatitis

- Long acting injectable antibiotic e.g. Tilmicosin
- Topical oxytet
- Quarantine new sheep


Outline the aetiology of toe granulomas in sheep

- Non-infectious
- Either from chronic unresolved footrot
- Or overtrimming into sensitive part of foot


Outline the treatment of toe granulomas in sheep

- Very difficult, need to cut away granuloma
- Ring block using 2% lidocaine or IVRA into superficial leg vein of 2% lidocaine 10ml max
- Pare away loose and underrun horn , expose base of granuloma
- Must have tourniquet on leg before cutting away granuloma at base
- Cauterise site of granuloma with hot iron
- Ensure no bleeding


Outline the aftercare following treatment of a toe granuloma in sheep

- Do not bandage
- Dress with antibiotic aerosol spray e.g. oxytet
- If necessary use parenteral antibiotic (e.g. footrot) - pen+strep 2x normal dose, oyxtet normal dose


Outline the aetiology of white line disease in sheep

Unknown, may be similar to other species


What is shelly hoof in sheep?

- Presentation of white line disease where soil/debris accumulates laterally at white line
- Half moon appearance of separation of white line
- Often no lameness until abscess then acutely lame
- No underrunning of hoof


How is shelly hoof treated?

Trim back and expose pocket


Describe the typical presentation of toe abscesses in sheep

- Sudden onset extreme lameness with pain and heat, no obvious swelling
- Small localised black spot at white line
- Pus may track up and break out at coronary band


Outline the treatment of toe abscesses in sheep

- Do not trim acute cases
- Avoid parenteral antibiotics until pus has burst out - poultice foot to encourage this


Describe the variety of white line separation lesions that may occur in sheep

- Minor: usually no infection, not lame, short distance of separation, not detected unless pare foot along WL
- Moderate: no infection, not usually lame, half moon appearance once pared
- Major: shelly hoof, when detached wall is trimmed see half moon appearance, impaction of mud/debris, pus


Outline the treatment for white line disease with extensive separation

- Pare away detached horn, care not to go too deep
- Antibiotic spray if infected
- If pus burst out, no paring
- Leave to recover for at least a week, after which loosened horn pared away carefully


Outline the treatment of early acute cases of white line separation

- Careful paring along course of white line, may release pus
- Not too deep
- If pus found, poultice foot for 1/2 days to soften horn and encourage bursting


Discuss the use of parenteral antibiotics in the treatment of white line disease in sheep

- May delay resolution of separation
- Antibiotics used in expensive pedigree animals


How do foot abscesses develop in sheep?

- Often sequel to trauma or infection
- May follow excessively strong foot bathing


Give your differentials for the following clinical signs in a sheep:
- Extreme pain, swelling and heat in the foot
- Discharging sinus at the coronary band releasing pus

- Foot abscess
- Toe abscess
- White line disease
- Contagious ovine digital dermatitis (Coronary band involvement)


Discuss the use of foot trimming in sheep

- Routine foot trimming has no benefits, but can cause lameness
- Trimming horn may delay healing in foot rot
- Overgrown feet does not cause lameness, but may become overgrown if infected


Outline the five point plan for footrot in sheep

- Avoid spread of infection
- treat individuals quickly and effectively
- Quarantine brought in sheep
- Cull out persistent offenders
- Vaccinate to protect against foot rot


After how many incidences of lameness should a sheep be culled?

2-3 incidences of lameness


When would the vaccine against foot rot be most effective?

Best used if have a high level of lameness, in order to reduce to a level where other methods can then be used instead, but always use in conjunction with other methods


Discuss the use of footbathing for the prevention of footrot

- Footbath must be clean, clean feet before use, stand on hard surface after footbathing
- 10% zinc sulphate for at leas 2 mins, or 3% formalin as walk through
- Will not TREAT footrot


List the management factors that influence lameness in pigs

- Flooring
- Housing system
- Stocking density and group size
- Growth rate
- Nutrition


Outline the lesions may develop in pigs as a result of slatted floors

- Sole bruising in piglets, heel flaps in older pigs
- Bursitis and capped hock in older pigs
- If sharp edges, coronary band injuries in piglets


Outline the lesions that may develop in pigs as a result of solid concrete floors without bedding

- Hard: sole bruising in piglets, bursitis and capped hock in older pigs
- Rough: sole erosion in piglets, skin abrasion in piglets, calluses in older pigs


Outline the lesions that may develop in pigs as a result of solid floors with bedding

- Soft: hoof overgrowth in older pigs
- Damp: toe erosion in older pigs


Discuss how housing system influences lameness in pigs

- EU requirement to group house sows from 4 weeks after service until one week before farrowing
- Group is more natural, social interaction, increased exercise, less superficial joint damage
- But also increased aggression leading to lameness, claw lesions, body lesions
- Stable groups reduce this risk


Discuss how group size and stocking density influence lameness in pigs

- Pigs in larger groups tend to have higher limb lesions and lameness scores
- Increased lameness later in finisher stage especially due to increased body size


Discuss how growth rate influences lameness in pigs

- Leg weakness more evident in pigs with higher lean tissue growth rates
- Every 100g increase in daily gain results in an increase of 20% in the risk of exhibiting signs of OCD


Discuss how nutrition influences lameness in pigs

- Directly related to claw, bone and cartilage physiology, direct affects limb healthy via weight gain
- Vitamins and minerals important
- Feed specific diets to replacement gilts to support bone development and fat deposition


List the 5 most common infectious/congenital causes of lameness in pigs

- Bacterial arthritis
- Erysipelas
- Splayleg
- Mycoplasma
- OCD (leg weakness)


What is bacterial arthritis in pigs also known as?

Joint ill


List the pathogens commonly involved in bacterial arthritis in pigs, indicating which is the most important

- Strep suis (most important)
- Actinobacillus suis
- Haemophilus parasuis (Glassers disease)
- Trueperella pyogenes