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Karteikarten

Lameness in Cattle

Rebecca Hitchman 2 Clinical Veterinary Science Englisch 163 Karten

Lameness in Cattle

Karten in diesem Stapel (163)

  1. 1What are the top 3 problems facing UK diary industry?- Welfare
    - Health
    - Cost
  2. 2What is the Incidence of Lameness?cases/ 100 cows/ year
    However, cases on farms poorly recorded, typically 50 range 10-170
  3. 3What is the Prevalence of Lameness?(% affected at a point in time)
    ~ 36.8%
    Range: 0-79%
  4. 4What is the impact on the cow when lame?- Pain & discomfort
    - Behaviour changes: incr. lying times, reduced feed intake, suppression of oestrus expression, reduced visits to robot in automatic milking systems
  5. 5What Direct costs are Ass. with Lameness?- Treatment costs
    - Vet time
    - Farmer time
    - Milk discard
    - Decr. milk yield
  6. 6What indirect costs are Ass. with Lameness?- incr. risk of culling
    - effects on fertility (takes ~40 more days to get back into calf)
    - risk of further lameness cases
    - risk of secondary disease
  7. 7What are the most and least costly causes of lameness?most cost ass. w/ Sole ulcer
    mid-range ass. w/ Digital case
    least costly: inter-digital case
  8. 8What is the Average case of Lameness?Direct : £71.70
    Indirect: £99.86
    Total: £171.56
    Average 100 cow herd - £3860
    National herd (2.35 million) - £91 million
  9. 9What are components of the Cow Claw (Hoof)?The coronary band: junction between skin and horn, produces the wall horn
    The wall: formed at a rate of 5mm/month, migrates down hoof
    The Periople: junction between skin and horn at coronary band, forms waxy coat for hoof
  10. 10—
  11. 11What are components of the Cow Claw (Hoof) palmer/planter surface?The sole: formed from papillae on sole, wall and sole meet at white line
    The White Line: join between wall and sole, point of weakness
    The Heel: Soft sponge horn
  12. 12Where does the Distal Phalanx sit within the claw?AKA: pedal bone (P3)
    - located centrally within hoof, maily attached to dorsal wall, flexor tendon attached to palmar/plantar edge, navicular bone between tendon and P2
  13. 13What is the Corium and which structure is it associated with?Ass. w/ P3:
    The corium is composed of strum germinativum which produces the horn.
    - Fills space between sole and P3 therefore vulnerable to pinching
    - contains blood vessels, nerves and other support structures
    - VERY sensitive
  14. 14What is the role of the Digital Cushion and what structure is it ass. w/?- Pad of fat and elastic tissue that acts as a shock absorber. Is a thin layer and if cows are too thin, this layer will be even thinner
    - Pumps blood from foot
    - Sit underneath P3 and prevents it impinging on the corium
  15. 15What is the role of the Laminae and what structure is it Ass. W/ ?- Junction between the wall and P3
    - Sensitive and insensitive components: sensitive dermal laminae from P3
    insensitive epidermal laminae from hoof wall
    - Interdigitate like interfacing fingers
    - Suspends P3 within the hoof capsule
    - Affected by hormonal changes around calving
  16. 16What are the normal dimensions of the claw?Anterior wall: 75mm (60-90mm)
    Anterior wall to ground: 45-50 degree
    Heel height: 25-35mm (young), 30-45 (old)
  17. 17What affects Horn growth?- Slow: ~ 5mm/month
    Affected by:
    - Loading (incr. loading = incr. growth)
    - Claw (outside > inside on the hind feet)
    - Nutrition
    - Age/Breed
  18. 18Where does Horn growth start?Wall growth: starts from the coronary band and moves down towards the toe
    Sole growth: starts from the sole corium (quick) and moves down and forwards
  19. 19What Affects the Horn quality?- Lameness
    - Damage to the corium or coronary band
    - underfoot conditions
    - Foot bathing: poor quality may cause weakened horn
    - Systemic illness
    - Nurtition (e.g. Low Biotin or high concentrates)
    - Breed/ Age
  20. 20What Cow factors affect horn wear?- Horn quality
    - Hoof conformation
    - Limb conformation
    - Udder size and structure
  21. 21What External factors affect horn wear?- Underfoot conditions:
    Surface abrasiveness e.g. concrete vs gravel
    Slurry depth
  22. 22What Management factors affect horn wear?- Walking distance
    - foot trimming
    - housing programme
  23. 23On which structures of the claw does normal weight bearing occur?- On the WALL of the foot: that means the toe wall, axial wall, abaxial wall and heel
    - Soome weight is on sole but need to ensure do not trim these areas
  24. 24What is the normal weight bearing surface of the Forelimbs?Holds 60% of bodyweight
    - Carried more on the INSIDE claw therefore has larger inside claw
  25. 25What is the normal weight bearing surface of the HIndlimbs?- 40% of bodyweight
    - more carried on the outside claw, therefore larger outside claw
  26. 26How does Toe overgrowth occur?- in housed cattle the wall is worn more rapidly at the heel
    - heel undermined by slurry heel in winter
    this leads to further overgrowth at toe (non weight bearing) , and shifts weight further back (<45degree), the sole corium is pinched causing pain whilst walking, sole bruising/ haemorrhage leading inflammation/ sole ulceration
  27. 27How does sole overgrowth occur?- overgrowth at toe leads to thickening of the sole in this region
  28. 28When does disparity of claw size?Weight bearing on lateral hind claw,
    Irritation and sole overgrowth, incr. pressure & pain in lateral claw, abduction of the limb, incr. weight on medial claw, decr. wear on lateral claw, overgrowth at toe forces hocks together and decr. weight bearing on lateral claw
  29. 29What is the aim of the Dutch 5 step technique?- Aims to create a normal balanced foot: correction of overgrowth and even weight bearing
    - Allows diagnosis and treatment of lameness prevents new lameness
  30. 30What is Step 1A of Dutch 5 Step technique?Start w/ medial claw for hind-limbs and lateral claw for fore-limbs
    Make the first cut at the toe, to make the wall 75-85mm in length
    (start by smaller amount off first)
  31. 31What is Step 1B of Dutch 5 Step technique?- Level off the claw, but removing sole to leave 5-8mm step at the toe
    - This is done with a knife on the FRONT 2/3 of the Foot only (NOT HEEL)
    - Use both hands on knife
  32. 32—
  33. 33What is Step 2A +B of the Dutch 5 Step technique?- Move onto the other claw
    In Hindlimbs this will be the OUTER claw, in Forelimbs this will be INNER claw
    A: - Make the first cut to get wall length 75-85mm (to match the other claw)
    B: Level off the claw using a knife and removing front 2/3 of foot to make toe step matching other claw
  34. 34What is Step 3 of the Dutch 5 Step technique?Modelling stage:
    - Remove weight bearing from the sole at the middle 1/3 of the foot
    Hindlimbs: lateral claw make a wider and shallower cut, medial claw: deeper and narrower cut
    Forelimbs: the reverse of above
  35. 35What is Step 4 of the Dutch 5 Step technique?TREATMENT
    - identification of lesions: may use hoof testers
    - Corrective trimming to treat the lesion
    - Adjustment of weight bearing away from the painful claw
    - Is specific to different lesions
  36. 36What is Step 5 of the Dutch 5 Step technique?LOOSE HORN
    - remove loose horn and irregular ridges
    - particularly around heel
  37. 37What is the summary of the Dutch 5 Step Technique to Hoof care for HINDLIMBS?1. Inner claw: A- length, B- level
    2. Outer claw: A- length, B- level
    3. Modelling
    4. Treatment
    5. Loose horn
  38. 38What is the summary of the Dutch 5 Step Technique to Hoof care for FORELIMBS?1. Outer claw
    2. Inner claw
    3. Modelling
    4. Treatment
    5. Loose horn
  39. 39What is the benefit of preventative foot trimming?- Rebalance weight bearing
    - manage lesions
    - Improve grip and gait
  40. 40What is the recommended frequency of foot trimming?There isn't one! Depends on the farm management methods, most about twice a year. Maybe less if on abrasive ground, or more if on softer ground
  41. 41What is the recommended timing of foot trimming?- For optimal feet at calving?
    As calving effects ligaments which loosens the hold. P3 more likely to rotate
  42. 42What are causes of lameness in cattle?Claw horn lesions:
    - Sole ulcers (note poor foot trimming incr. risk of sole ulcers)
    - White line disease
    - Local sole bruising
    Soft tissue lesions:
    - digital dermatitis
    - foul in the foot
  43. 43What is the Aetiology of Sole Ulcers?- Disruption of claw horn formation:
    - pinching of corium between bone and hoof capsule
    - pressure on corium causes degeneration "coriosis"
    - Rotation of P3 can occur due to relaxation of support around calving time
  44. 44What increases the risk of Sole ulcers occuring/ make them worse?- standing on concrete
    - thin cows (thin digital cushion)
    - poor foot conformation/ insufficient routine foot trimming
    - Also dairy cows altered gait due to big udder.
  45. 45What are the clinical signs of Mild Sole ulcers?incorporation of blood into horn (sole haemorrhage). may not cause lameness but unsure if impact diet & milk yield etc.
    -Indicates there is problem that must be fixed within herd
  46. 46What are the clinical signs of Severe Sole ulcers?- Horn production is completely arrested = sole ulcer
    Remember need to look back at what happened couple months ago as would take that long to reach bottom of foot (growth is ~5 mm/month)
  47. 47What is the Presentation of Sole Ulcer?- Often present on both hind-feet (one worse than other)
    - lateral claw of hind feet, medial claw of fore-feet
    - Haemorrhagic discolouration leads to complete cessation of horn production at sole ulcer site
    - May get secondary infection: deep digital sepsis in extreme cases
  48. 48How can sole ulcers be diagnosed?- pathognomic once foot inspected and trimmed
  49. 49What is the Treatment for Sole Ulcers?- need to decr. pressure on pinched corium
    - corrective trimming (need to trim surrounding area to 1 cm higher to prevent weight bearing on lesions) and decr. height of affected claw & dish
    - remove underrun horn and granulomas if present
    - foot blocks
    - Astringets? e.g. CuSO4 (not used)
    - NSAIDs (YES! is painful!!)
  50. 50What is the Prognosis of Sole Ulcer?- simple horn overgrowth - good
    - chronic coriosis: may require regular corrective trimming, recurrent sole ulcers & may never walk properly again
    - Deep digital sepsis = poor prognosis
  51. 51How can Sole Ulcers be Prevented?- Impossible to prevent underlying changes
    - Must manage/minimise risk: regular foot trimming to prevent overgrowth
    - good underfoot conditions
  52. 52What is the Aetiology of White line disease?- Junction of sole & wall - area of weakness
    - Coriosis leading to softening and widening
    - dirt and stones impact leads to infection carried through to corium
    - White line seals over causing the infection to be trapped causing pus produced & expands within potential space leading to pain
    - Usually under sole
    - Occasionally up the wall
    - Eventually pus breaks out, usually at heel or coronary band (relieving some of the pain)
  53. 53On which claw does white line disease occur most commonly?- More common on Lateral claw but can be seen anywhere
  54. 54What are the Clinical Signs of White Line disease?- moderate to severe lameness (position & extent of abscess)
    - Lateral claw more commonly affected
    - Swelling - advanced +/- large abscess
    - Leg abducted to bear weight on medial claw
  55. 55How is White line disease diagnosed?- White line impaction & abscess if trimmed and explored
    - Small pin prick size holes to large areas of impaction (always black)
    - Pain if "tweak" claw
    - If unsure can use hoof testers
  56. 56How can White line disease be treated?- must trim until opened up to release pus
    - trim and balance both claws
    - explore impacted white line, drain abscess, remove under run sole (at least enough to prevent re-impaction)
    - if up wall remove entire section
    - AB dressing? for 48hrs max
    - Use of foot blocks
    - Parenteral ABs- necrotic corium
    - Give NSAIDs
  57. 57What is the Prognosis of White Line Disease?- Good: simple sole abscesses respond well, however tracks up wall are much more difficult to treat
    - Be careful to deep digital sepsis
  58. 58How can White line disease be prevented?- Control coriosis
    - Underfoot condition e.g. sharp stones, rough concrete
    - Avoid walking long distances on hard surfaces or rough tracks
    - biotin (given as supplement, generally in concentrates)
  59. 59What is the Aetiology of Digital Dermatitis?- Spirochete bacteria: Treponema medium, T. phagadenis and T. pedis
    - Likely deep tissue invasion
    - spreads in contaminated slurry/ water
    - fomite spread e.g. knives
    - subclinical carrier status
  60. 60What are the Clinical Signs of Digital Dermatitis?- Variable lameness caused
    - small circular (1-4cm), moist browny grey exudative areas of epidermal liquefaction and matting of the surrounding hair
    - interdigital area behind heel bulbs
    - Occasionally on skin above one heel bulb only, interdigital space between claws, coronet at front of the foot, accessory digits
    - Raw dermal granulation tissue if diphtheritic debris cleaned leading intensely painful
    - 'Papilliform' or 'hairy warts' form: long thick strands of keratin protrude from the underlying granulation bed.
  61. 61Which form of Digital Dermatitis is the worse prognosis?- 'Hairy wart' stage: most chronic
  62. 62What are the stages of Digital Dermatitis?M0 = normal healthy feet
    causing: M1= subclinical, lesions non painful <2cm grey
    leads to: M2 = active lesion, red, ulcerative >2cm
    either leads to M3 = healing stage, scab formation
    OR to M4.1= chronic lesions that has relapsed
    M4= chronic lesion
    The infection can move between any stage depending on if getting better or worse
  63. 63How is Digital Dermatitis Diagnosed?- Examine and clean: pathognomonic lesions
  64. 64What is the Treatment for individuals with Digital Dermatitis?- clean, remove matted hair and "scab"
    - dry, apply topical tx: antibiotic (oxytetracycline sprays, soluble powders e.g. lincospection, tylan)
    - Non-antibiotic: copper/zinc containing gels
    CLEANING IS MOST IMPORTANT
    - Second application when dry?
    - Repeat next few days?
    - Systemic ABs?
  65. 65How can Digitial Dermatitis be treated on a herd level?- use of footbaths:
    - ensure feet are clean first
    - tx bath: water, dilute hypochlorite (parlour washings)
    - 2 to 5% solutions of formalin or copper sulphate
    - 2-7 days/week, every week
    - Foot bath design must be 3m+
  66. 66Are Antibiotic Footbaths suggested in Treatment of Digital Dermatitis?- NO!
    - Is not a responsible use of AB
    - 7 days milk withdrawal and 28d meat withdrawal
    - Supervise?- toxic esp. lincospectin
    - would need measuring of foot bath volume and AB dilution carefully
    - Dispose in slurry lagoon? environmental impacts
  67. 67What is the Prognosis for Digital Dermatitis?- Good
    In front of foot: damages periople causing impaired production of wall which causing under running and vertical wall cracks
    - Herd immunity tends to develop with time
    - Herd eradication unlikely
  68. 68How can Digital Dermatitis be Prevented?- Improve winter hygiene (incr. scraping, incr. bedding
    - Hygiene of foot trimming equipment (preferably have own or make sure see disinfection)
    - Antibiotic (in outbreak, use in quarantine)
    - Disinfectant (formalin, CuSO4)
  69. 69What is Digital Dermatitis linked with?- Involvement in "non-healing" sole ulcers and white line lesions
    : no true evidence but anecdotal reports
  70. 70What are "Non-healing claw lesions"?- Acute onset, sever claw lesions
    - Has stippled appearance
    - Seen in herds with DD presence
    - DD pathogens have been found in these lesions
    - Difficult and unrewarding to treat
    - Can result in digit amputation (LAST RESORT)
  71. 71What is the "official" name for "Foul"?- Interdigital Necrobacillosis
    aka, Foul in the Foot, Claw Ill, Lewer
  72. 72What is the Aetiology of Foul?- Acute necrotitising inflammation of interdigital skin
    Can be caused by: Fusobacterium necrophorum +/- Secondaries (T.pyogenes, Streptococcus spp.)
    Damage to skin e.g. by FB, rough underfoot condition e.g. stubble or course straw predisposes
  73. 73What are the Clinical Signs of "Foul"?- Sudden onset moderate to severe lameness
    - Swelling of soft tissues above and around the coronary band and between the digits (digits get forced apart)
    - Swollen, hot, inflamed and painful to the touch
    - "Split" which discharges pus and lumps of necrotic tissue
    - Swelling may track higher up the leg as infection invades
    - Anorexia, drop in milk yield, weight loss and pyrexia
  74. 74How is "Foul" Diagnosed?- Signs are pathognomonic once foot examined
  75. 75How can "Foul" be treated?- Check interdigital space for FB's
    - Wash and flush with plenty of clean water
    - Debride necrotic tissue, topical AB
    - Parenteral AB - milking/ beef/ cost/ withdrawal ~3 days?
    - Oxytetracyline, penicillin and penicillin/ streptomycin combinations, tylosin (Tylan) and ceftiofur (excenel, zero milk withhold period/ 3rd gen Ceph)
  76. 76What is the Prognosis for "Foul"?- Good if treated early
    - Deep digital sepsis may occur in which case poorer prognosis?
  77. 77How can "Foul" be Prevented?- Improve underfoot conditions e.g. incr. mucking out
    - Formalin foot baths
  78. 78—White line diseaseWhite line disease
  79. 79—Sole UlcersSole Ulcers
  80. 80—"Foul""Foul"
  81. 81—Sole BruisingSole Bruising
  82. 82—Digital Dermatitis, less severe caseDigital Dermatitis, less severe case
  83. 83—Digital Dermatitis Sever CaseDigital Dermatitis Sever Case
  84. 84What are less common causes of lameness in Cattle?- Foreign bodies
    - heel ulcers, toe ulcers,
    - toe necrosis
    - Laminitis
    - Sole bruising
    - heel erosion
    - Vetrical and Horizontal fissures
    - interdigital growths
    - deep digital sepsis
  85. 85What is the Aetiology of FB penetration?- penetration of sole (NOT white line) w/ objects from the environment
    - E.g. nails, sharp stones, pieces of metal & glass, palm kernal and cast teeth
    Will carry infection leading to sub=sole abscesses
  86. 86What are the Clinical Signs of FB penetration?- Similar to White line disease although lameness is often acute in onset and severe if FB still present
  87. 87How is FB penetration Diagnosed?- Straight forward if FB still present
    - Otherwise explore track in sole
  88. 88How is Digital Dermatitis Treated?Same as WLD:
    - must trim until opened up to release pus
    - trim and balance both claws
    - explore impacted white line, drain abscess, remove under run sole (at least enough to prevent re-impaction)
    - if up wall remove entire section
    - AB dressing? for 48hrs max
    - Use of foot blocks
    - Parenteral ABs- necrotic corium
    - Give NSAIDs
  89. 89What is the Prognosis for FB penetration?- As for WLD: good as long as no deep digital sepsis has occurred
  90. 90How can FB penetration be Prevented?- Keep environment free of FB (DIFFICULT!)
  91. 91What is the Aetiology of Heel Ulcers and Toe Ulcers?- Penetration of sole
    - overgrowth of the toe and fissures
    - iatrogenic (improper foot trimming / thin soles)
  92. 92What is the Diagnosis for Heel and Toe Ulcers?- Ulcers at sites away from the classical "sole ulcer site"
  93. 93What is the Treatment for Heel and Toe Ulcers?As for Sole Ulcers:
    - need to decr. pressure on pinched corium
    - corrective trimming (need to trim surrounding area to 1 cm higher to prevent weight bearing on lesions) and decr. height of affected claw & dish
    - remove underrun horn and granulomas if present
    - foot blocks
    - Astringets? e.g. CuSO4 (not used)
    - NSAIDs (YES! is painful!!)
  94. 94What is Toe Necrosis?Aka: "Rotten toe"
    - likely secondary to toe ulcer or a split in the horn
    - Deep infection often involving soft tissue/ bone
    - Often require extensive remodelling to remove affected tissue
    - Guarded prognosis
  95. 95What is the Aetiology of Laminitis in Cattle?Ruminal acidosis causes bacterial death and leads to bacterial endotoxins
    - Acute toxic condition e.g. mastitis/ metritis causes bacterial death leading to bacterial endotoxins
    This leads to vasoactive mediators causing vasodilation and paralysis of blood vessels in corium
    - Arterio-venous shunts open bypassing the corium and the capillary walls suffer hypoxic damage resulting in the escape of serum and eventually rbc's
    - Oedema potentates situation causing pain, corium trapped between navicular bone and hoof capsule
  96. 96Why must the term Laminitis be used carefully when referring to cattle?- Laminitis is sometime used to refer to CORIOSIS, but true laminitis can occur
  97. 97What is Sole Bruising?- Is DIFFERENT from Sole Haemorrhage!
    - Part of spectrum of disease caused by coriosis: sole haemorrhage -> sole ulcer
    - laxity of ligaments around calving causing movement of P3 which compresses on the corium.
    - Can also occur due to incr. standing times and standing on concrete, overgrowth of hoof etc.
  98. 98What is the Aetiology of Sole bruising?- Turn sharply on hard surfaces (bullying)
    - Soft bedding to rough concrete
    - soft feet (standing in water of slurry)
    - Dismounting (bulls and cows)
    - Laminitis
  99. 99What are the Clinical signs of Sole bruising?- Low grade lameness
  100. 100How is Sole bruising diagnosed?- Bruising if examined and trimmed (NB may take weeks to appear)
    - Diffusely on sole (not SU site)
    - Pinch w/ hoof testers
  101. 101How can Sole Bruising be Treated?- Conservative - trim to decr. overloaded claws, soft bedding? blocks?
  102. 102How can Sole Bruising be Prevented?- routine foot trimming (but care not to over- trim)
    - Optimal underfoot conditions
  103. 103What is the Aetiology of Heel Erosion? And the Clinical Signs?AKA: "Slurry heel"
    - Standing in wet corrosive faeces and silage effluent
    - Erosion of soft heel horn causing pitting and fissures
    - if severe, heel almost completely disappears
    - usually asymptomatic but can lead to other diseases e.g SU
    - Cow will start rocking backwards leading to P3 rotation
  104. 104How can Heel erosion be diagnosed?- Often seen during trimming (routine & lame)
    - is usually an incidental finding
  105. 105How can Heel erosion be Treated?- Formalin foot baths to harden feet
    - Timming to restore foot balance, remove loose horn but DO NOT remove healthy heel horn
  106. 106What is the Prognosis of Heel erosion?- Good if treated early
    - if left, heel disappears causing backwards rotation of foot and leads to overgrowth of toe and sole ulceration
  107. 107How can Heel erosion be Prevented?- Optimal underfoot condition (do not allow to stand in faeces, water of silage effluent etc)
    - Regular formalin foot bathing
  108. 108What is the Aetiology of "Heel fissures"?- Periople produces waxy layer, prevent wall drying out
    - If damaged wall dries may crack vertically
    - Damage to corium leads to defective wall production
    - Hot dry sandy conditions in summer
    - Also damage to germinal tissue at coronary band e.g. DD
  109. 109What is the Clinical Signs of Vertical Fissures?Often asymptomatic
    lameness if corium pinched or infected
  110. 110What is the Diagnosis of Vertical Fissures?- Pathognomonic once foot examined (can often see the fissure when animal standing)
  111. 111What is the Treatment for Vertical Fissures?- Trim out crack
    - drain abscesses + expose any necrotic corium
    - Can lead to movement between two section of wall causing granulation tissue formation
    - Resect and block
  112. 112What is the Prognosis of Vertical fissures?- Moderate: can be difficult to treat unless defect in wall starts growing out from coronary band
    - May take a long time and multiple trims
    - If periople/ coronary band damaged long term prognosis is poor
  113. 113What is the Aetiology of Horizontal Fissures?- Complete circumferential horizontal
    - Severe toxic condition e.g. mastitis, metritis or acute acidosis causing temporary but complete absence of horn production
    - Often complete circumferential fissure round all 8 claws
    - Interruption of wall production may not be complete causing thinning of wall only (hardship lines)
  114. 114What are the Clinical signs of Horizontal fissures?- often asymptomatic unless:
    laminae become infected
    movement causes production of granulomas
    - Many are clinical when "thimbles of horn" grow out at toe causing incr. movement which in turn leads to infection and granulomas
    - Chronic to acute onset lameness, often multiple feet
  115. 115What is the Diagnosis for horizontal fissures?- Signs are pathognomonic
  116. 116What is the Treatment for Horizontal fissures?- Open and trim cracks, drain and expose abscess adn necrotic corium, remove granulomas if present
    - all claws, must establish which is causing lameness
    - Blocks: may be difficult as often all 8 affected
  117. 117What is the Prognosis for Horizontal Fissures?- Depends on severity, if severe on all claws the prognosis is poor and difficult to manage
  118. 118What is the Aetiology of Interdigital Skin Hyperplasia?AKA Interdigital Corns/ Fibromas/ Growths/ Granulomas
    - Normally two small flaps of skin (one either side)
    - Chronic irritation of the interdigital area
    - Infection or impaction of dirt/ small stones
    - Chronic lesions/ abnormal gait and poor foot conformation
  119. 119What are the Clinical signs of Interdigital Skin hyperplasia?- usually asymptomatic
    - lameness if infected or pinched during locomotion causes further incr. in size
    - Complicated by "foul" infections
  120. 120How can Interdigital Skin Hyperplasia be diagnosed?- Straightforward
    - Often asymptomatic so care in case it is not the cause of lameness
  121. 121What is the Treatment of Interdigital Skin Hyperplasia?- If infected/ evidence of foul, AB's will often resolve the lameness
    - In mild cases trimming (remove horn from interdigital space)
    - If no resolution, resection under IVRA or local anaesthesia. Remove and bandage + ABs
  122. 122What is the Prognosis of Interdigital Skin Hyperplasia?- Good
    - Recurrence common
  123. 123How can Interdigital Skin hyperplasia be prevented?- ensure optimal underfoot condition in winter
    - ensure optimal foot conformation
  124. 124If surgery of the digital is undertaken, which local anaesthetic is licensed to be used?Procaine
  125. 125How can Fracture of the distal Phalanx be Diagnosed?- Is difficult!
    - Acute onset lameness
    - Cross legged stance
    - No other lesions detected in foot
  126. 126How can Fracture of the distal Phalanx be Treated?- NSAID
    - Deep straw bed
    - Cull
  127. 127How does Deep digital sepsis occur?- Complication of other disease: e.g. sole ulcers, WLD, Foul, horizontal and vertical fissures
    - Infection gains entry to deeper structures of foot:
    + digital cushion, P3, P2, Distal interphalangeal joint, Flexor tendon, flexor tendon sheath, nevicular bone, navicular bursa
    + can not recover unless nectrotic tissue removed and allowed to drain (salvage)
  128. 128How can Deep digital sepsis be Treated?- Digit Amputation:
    + surgical removal of affected digit, is effective, relatively easy and cheap but Welfare implcations
    - Navicular bone resection
    - Drilling and flushing AB are not useful
  129. 129What is the key to a successful outcome?Therapeutic foot trimming:
    if detected early than treatment more effective, less relapses, less complications (e.g. deep digital sepsis), lower tx costs, less culling and lower costs ass. w/ losses
  130. 130What is the process of Therapeutic Foot Trimming?1. Identify the lame claw by watching the animal walking
    2. Safely restrain- use of foot crush
    3. Correctively trim the whole foot using Dutch 5 step technique- close attention to Step 4 explore lesions
    4. Check all soft tissue structures and dorsal wall of hoof!
  131. 131What are the basic principles of a lesions?- isolate lesion
    - remove under run and diseased horn
    - decr. weight bearing on disease claw
    - foot blocks
    - bandages?
  132. 132How is LA given when foot trimming lesions?- Local infiltration e.g. Field block, ring block
    - nerve blocks
    - I.v. regional anaesthesia (IVRA)
    Remember: Procaine is the one used!
  133. 133How is LA given when Therapeutically foot trimming?1. Apply tourniquet just below hock after giving area a quick scrub
    2. Identify vein
    3. 15-20ml Procaine, 5-10 mins onset of action but care not to leave on too long as forms necrotic & anaerobic environment
    4. Carefully remove tourniquet
  134. 134What is the aim of using Foot blocks?- decreases weight bearing on diseased claw allowing it to heal
    - must be glued on
    - need removal if still present after 4-6weeks
    - evidence supports use in treatment of claw horn lesions
  135. 135Are NSAID indicated when foot lesion present?YES!
    - Evidence to support benefit over trimming alone
    Ketoprofen - 0 day milk withdrawal
    Meloxicam - longer analgesic effect
    But barriers to use: cost, foot trimmer treating cows etc.
  136. 136How are Dressings used in Treatment of Foot lesions?- protect diseased area
    - apply topical treatment - astringents, antibiotics
    - now less popular
    - incr. weight bearing on diseased claw?
    - 48 hrs max.
    - except digit amputations & surgical removal of interdigital growths
  137. 137When is Digit Amputation Indicated?- deep digital sepsis
    - Toe necrosis
    - Non-healing WLD/ SU
    - Trauma, degloving or disarticulation (uncommon)
  138. 138What are Pre-operative considerations for Digit amputation?- must consider if culling is more appropriate
    - how good is post-op care?
    - analgesia and palliative care: is the cow likely to be less painful in the longer term?
    - environmental conditions
    - likely prognosis (will she be lame on another leg?)
  139. 139What are the contraindications to digit amputation?- imperfect contralateral claw.
    - Sever, ascending tenosynovitis
    - lameness affecting another limb
  140. 140What is the Surgical approach to digit amputation?1. Apply tourniquet and give IVRA
    2. Hemi-circumferential incision app. 1 cm proximal to the coronary band through the skin, subcutaneous tissues and tendons
    3. Make a second longitudinal incision in the interdigital space to meet the original incision at both ends
    4. Place clean embryotomy wire into the incision at the level of P2 (is best to got through as get better healing) and make a transverse cut
    5. Apply a pressure bandage
  141. 141What is the Post- operative care of Digit Amputations?- will have some strick-through when tourniquet removed
    - Change the pressure bandage every 48hrs until a complete, healthy layer of granulation tissue has formed
    - Systemic antibiotics for a minimum of 5 days
    - Repeat NSAIDs as required if the cow appears painful
  142. 142What are the complications that can occur with Digit Amputation?- haemorrhage
    - infection: dehiscence, osteomyelitis or ascending tenosynovitis
    - Ischaemia and sloughing
    - Premature culling
  143. 143What is the Prognosis following Digit amputation?- Generally guarded
    - Highly dependent on the quality of post-op care and the indication for amputation
    - should be viewed as a salvage procedure, should not be expected to calve in again
    PREVENTION IS BETTER THAN "CURE"
  144. 144—Horizontal FissuresHorizontal Fissures
  145. 145—Vertical FissureVertical Fissure
  146. 146—Laminitis aka coriosisLaminitis aka coriosis
  147. 147—Toe UlcerToe Ulcer
  148. 148—Heel UlcerHeel Ulcer
  149. 149—Toe NecrosisToe Necrosis
  150. 150What are the categories that must be considered when assessing risk factors for lameness in a herd?Environment
    Stockman
    Cattle
  151. 151What are Environmental factors that affect Lameness?- Cow flow
    - Concrete surfaces
    - cubicle comfort (lying and rising)
    - cow tracks
    - cow behaviour in standing areas
  152. 152What are Stockman factors that affect Lameness?- Nutrition
    - Trimming skills
    - Foot bathing
    - Time budgets
    - Cattle Handling
    - Policies
  153. 153What are Cattle factors that affect Lameness?- Mobility scores
    - Parlour lesion scoring
    - Health Record Review
  154. 154Environment What Affects Cow flow?Building design: blind ends (bullying), bottle necks, narrow doorways (crowding & pushing), tight corners, sharp protrusions, passageway width
    Stocking density
    Resources: location of feed/ water troughs, comfortable positioning to feed. Sufficient resources to prevent queueing - trough space (feed & water), brushes
  155. 155Environment What Affects Underfoot surfaces?- Flooring type: slipperiness/ grooving, rough concrete, rubber matting of key areas
    - Farm tracks
  156. 156Environment What Affects Cow comfort, standing and lying times?Cubicles: number/ stocking density (remember need 5% extra cubicles for herd), grouping to prevent bullying e.g. separate heifers
    Lying surface: test with "kneedrop test", look at "comfort quotient", hock lesions
    Cubicle hardware/ design: watch cows stand/ lie down, positioning in cubicles
    Length of milking: standing time and surface in parlour & collecting yard
  157. 157Environment What Affects Underfoot hygiene?Scraping frequency: min 2x daily
    Check where areas of slurry build up/ pooling occurs
    - use of automatic scrapers?
  158. 158Environment How does Footbathing Affect Environment of Cows and Lameness?Frequency: ideally every milking
    Product: need to consider aim, hardening feet v cleaning? control pathogens, formalin, copper sulphate, parlour washing/ hypochlorite circulation wash
    Use of prewash/ cleanliness of feet before entry into milking?
    Footbath design: each foot should enter twice, and product should reach coronary band (long and deep)
  159. 159Stockmanship How does Foot trimming/ "foot checks" affect cow lameness?Adequately trained herds person or use of lay foot trimmer
    Frequency; all cows at drying off and post calving v whole herd trimmed annually/ in batches/ selecting overgrown feet
  160. 160Stockmanship How does Nutrition affect lameness in cattle?- Trace elements: adequate zinc, sulpher in diet good quality horn
    Biotin (20mg/day): has been shown to sig. decr. the incidence of WLD (by 50%)
    Avoid acidosis
    Body condition score: thin cows go lame, BCS <2 ass. w/ incr. lameness
  161. 161Stockmanship What Other factors can affect lameness in cattle?- Policies on stocking rates, cattle handling, patience whilst walking/ moving cattle, use of dogs, time budgets, foot bathing
    Identification of lame cows
    Nursing care
    Genetic slection: breeding from families w/ foot problems/ lameness, sire selection
  162. 162What Issues occur with Heifers (issues in 1st lactation) that can cause lameness?- Bullying/ social changes
    - Cubicles, may not know how to use them therefore incr. time standing
    - Incomplete digital cushion development
    - Udder development
    - Concrete - reared on straw or grass
    - nutrition? (less important)
  163. 163What Prevention strategies can be used with heifers to reduce lameness?- Cubicle training
    - transition diets
    - Introduce concentrates slowly (~4 wks)
    - Calve in summer (cubicles and building to themselves)
    - Separate group for first lactation: straw yards, esp. high yielding herds
    - Focus on first 60 days in milk
    - Trimming before 1st calving

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2 Clinical Veterinary Science (Lameness ) Karteikarten am Lameness in Cattle, erstellt von Rebecca Hitchman am 29/01/2019.
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Rebecca Hitchman
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