Cattle Lameness 2 Flashcards
What is the medical term for sole ulceration?
Pododermatitis Circumscripta
What is the aetiology of a Sole Ulcer and Haemorrhage?
–Flexor tendon attached to caudal edge of pedal bone Þ a bony protrusion
–Movement of P3 downwards (see Lecture 1) and/or claw overgrowth and/or external pressure e.g. standing on concrete Þ Pinching of corium and the germinal epithelium between P3 and hoof capsule. Leaves a defect
–Changes in the structure and function of the digital cushion may lead to poor / inadequate cushioning and the formation of new bone on P3 may exacerbate the problem
Label this
A) Bony protuberance
B) Digital Cushion
C) Slackening of strong attachments
What are the mild consequences of havng a sole ulcer and haemorrhage?
–Incorporation of blood into horn as the sole is produced
What are the moderate consequences of having a Sole Ulcer and Haemorrhage?
–Partial / intermittent interruption of horn production at the sole ulcer site. Weakness in the horn.
What are the severe consequences of having a sole ulcer and haemorrhage?
–Horn production completely arrested at the sole ulcer site for a prolonged period. Stop growing due to the pressure.
What are the clinical signs and presentation of a sole ulcer and haemorrhage?
- Slight to severe lameness (duration and extent)
- Often both hind feet (one worse than other)
- Predominantly on the lateral claw of hind feet and medial claw of fore feet
- Haemorrhagic discolourisation Þ complete cessation of horn production as sole ulcer site
- Possible secondary infection
- Deep digital sepsis (extension of infection into deeper foot structures) in extreme cases
- A normal trim may not find it as it starts at the corium! So advice coming back in a few weeks if lame.
What is this?
Sole Haemorrhage / Ulcer
What is this?
Sole Haemorrhage / Ulcer
Milder
How do you diagnose Sole Ulcer and Haemorrhage?
- Pathognomonic once inspected & trimmed
- Not uncommon to find digital dermatitis, white line and a sole ulcer – hard to distinguish cause of lameness
How do you treat sole ulcer and haemorrhage?
- Target: ¯ pressure on pinched corium
- Corrective trimming + ¯ height of affected claw & “dish” the site
–Leave the unaffected foot a bit thicker to act a a natural foot block
–Dish the site – remove the pressure
•Remove underrun horn and granuloma if present (with a sharp knife)
–Remove edge of horn which isn’t sensitive – preventing pinching.
–If you think its underrun and need to trim more – need to put LA in
- Apply a foot block to the sound claw and administer NSAIDs
- Parenteral antibiotics if infected
- Place on deep straw deep if severe
- (NB Astringents e.g. CuSo4 or cauterisation are now considered counterproductive
–Copper sulfate just kills of the corium whch is probably painful and we need the corium to grow the horn!!! Will just make it look less inflamed
–DO NOT USE HOT IRON – NOT OK – damages tissue
What is the prognosis for Sole Ulcer and Haemorrhage?
–Good in simple cases
–Poorer if:
- Multiple claws affected
- Severe
- Deep digital is present
What risk factors do we have at a herd level for a sole ulcer and haemorrhage? (4)
•Walking and standing for long periods on hard surfaces (e.g. concrete), especially in the post calving period
–This is a pressure lesion
•Hoof overgrowth
–Rotates the foot backwards
–Regular foot trimming
•Periparturient increase in the movement of the pedal bone
–Interventions needed at this time
•Lose of fat from the digital cushion and new bone formation on P3
–Manage BCS
What control measures do we have at a herd level to control a sole ulcer and haemorrhage?(3)
•Reduce walking and standing time on concrete (esp. around calving)
–Cubicle train heifers
–“Fresh cow groups”
–e.g. collecting yards and milking time
–Rubber matting over concrete (in areas the cow will spend a lot of time)
•Improve cubicle comfort to increase lying time
–Cubicle design
•Regular foot trimming to prevent overgrowth
What do you suspect?
Deep Digital Sepsis
What can you see?
Infection around NB tracking up into flexor tendon
What is the background and aetiology of digital dermatits?
I am so sorry the answer for this is so long.. It can’t be that important right?
–First identified in Italy (1972)
–UK (1983), now endemic
–A multifactorial infectious bacterial disease
•3 groups of spirochetes (primary?) plus other opportunistic / secondary invaders
–Group 1 – Treponema medium / vincentii like
–Group 2 – Treponema phagedenis like
–Group 3 – Treponema pedis
- One, two or all three groups required?? Currently unknown
- Gain entry to deeper tissues through hair follicles?
–Cattle (dairy & beef), Sheep, (Elk), (Goats), (Pigs), other members of the Ruminantia suborder?*
–Lesions on infected animals (main and possibly only reservoir)
•Major site likely to be the lesions itself
–Thought to transmit in slurry, although has been difficult to demonstrate definitively
–Causal bacteria have been demonstrated to survive on hoof knives. Route of transmission?
–Disease predominantly manifests when group of cattle and housed together
–Direct or indirect transmission from infected animals?
- Direct: Would require ‘foot to foot’ contact
- Indirect: Via fomites in the environment e.g. cubicle architecture, foot trimming equipment
–A host genetic susceptibility is likely
–A common disease which is poorly understood
–Risk factor – people with braces. Survives well on metal (link to periodontal disease)
–Research being done to understand if it can survive on hoof knives
What are the clinical signs of digital dermatitis?
–Mild lameness = Severe if not treated
–Interdigital area behind heel bulbs
–Small circular (1-4 cm), moist browny grey exudative areas of epidermal liquefaction + matting of the surrounding hair
–Raw dermal granulation tissue if diphtheritic debris cleaned = Intensely painful
–Occasionally skin above one heal bulb only, interdigital space between claws, coronary band at front of the foot, around accessory digits
–“Papilliform” or “hairy warts” form - Long thick strands of keratin protrude from the underlying granulation bed
–Painful – hard when trimming
–Almost always in the interdigital space
What classification system is used for digitial dermatitis?
M classification system
According to the m classifcation what is this?
M0
Normal digital skin without any signs of DD
According to the m classifcation what is this?
M1
Early, small circumscribed red to grey epithelial defect of <2cm diameter that precedes the acute M2 stage
Cow is not that lame at this stage! Not that uncomfortable
According to the m classifcation what is this?
M2
Acute, active ulcerative (bright red) or granulomatous (red-grey) digital skin alteration >2cm diameter
Touch touching dance
Hold foot up
Painful!
According to the m classifcation what is this?
Healing stage within 1 or 2 days after topical treatment, where the acute lesion has covered itself with a firm scab like material
Healing lesion; thick scab
According to the M classification system, what is this lesion?
M4
They can either heal or become this. Late chronic lesions that may be dyskeratotic (mostly thickened epithelium or proliferative or both. The proliferation may be filamentous, scab-like or mass proliferations
Keep develop keratin strands and develop hairy warts
According to the M classification system what is this lesion?
M4. 1
Relapse to an infected animal: Transition from 4 to a 1
Chronic lesion with subacute component(s)
According to the M classification system what is this lesion?
M4.1
Chronic lesion with subacute component(s)
What are the 3 “types” of digitial dermatitis animals?
Animal Type 1 – Does not develop M2 lesion but can show M1 and M4
Animal Type 2 – Single episode of M2, followed by prolonged period (months to years) of absence of acute DD
Animal Type 3 – Repeat episodes of acute M2 lesions (interval between episodes can be as short as 10-14 days)
What can be seen here?
Dermatitis – Very extensive lesion extending onto a granuloma in the interdigital space
What can be seen here?
Dermatitis – Lesion above one heel bulb only (unusual as normally in middle)
What can be seen here?
Dermatitis – Lesion at the coronary band
Very hard to treat!! - RARE
What can be seen here?
Dermatitis – Lesion at the coronary band
What is this?
Dermatitis – “Hairy wart” form. Now rarely if ever seen
Keratin strands forming from proliferative lesions
What can be seen?
Dermatitis – “Hairy wart” form. Now rarely if ever seen
What is this?
Digital dermatitis
How do we diagnose digital dermatitis?
Clean and examine – Pathognomonic lesions
How do you treat digital dermatitis?
–Clean, remove matted hair and “scab”
–Dry, apply topical antibiotic (Oxytetracycline sprays). Repeat applications (e.g. 3 days) improve recovery
–Alternatively bandage with antibacterial products
–Parenteral antibiotics are effective but may not be cost effective or justifiable (NB appropriate use of ABs)
–CARE – spread of infection to other animals on foot trimming equipment
How do you do a herd level treatment for digital dermatitis?
- Whilst historically (and currently) widely practices, it is now considered an unacceptable use of antibiotics, (see http://veterinaryrecord.bmj.com/content/181/2/51.2)
- This approach should no longer be recommended and should be phased out as quickly as possible
- Alternatives include targeted topical treatment following identification of animals with lesions in the milking parlour
- Evidence to absorb systemically
- Research with AB resistance – we should not do this
What is the prognosis for digital dermatitis?
–Good
•Respond very well to AB spray
–Except lesions on the front of foot Þ Damages periople Þ Impairs production of wall Þ Under running
–Newer presentations may be more difficult to treat
What are the herd level risk factors for digital dermatitis? (6)
- Housing (vs pasture)
- Wet and dirty conditions / environment
- Automatic scrappers?
–Limited evidence- the way they slide; slurry tidal wave (slurry washes over the cows feet)
- Herd expansion / poor biosecurity
- Younger cows
- High production
How can we control digital dermatitis?
Maintain a clean environment
Routine / regular foot bathing with disinfectants
What is the aetiology of white line disease?
–Junction of sole & wall – Area of weakness
–Similar to sole ulcers / sole haemorrhage (movement of P3, environmental risks and problems with the digital cushion, see above) leading to initial haemorrhage in the white line which may subsequently separate
–Weakness = attachment separates
–Separation exacerbated by:
- Stand and turning on concrete may damage the white line
- Dirt and stones impact = infection carried through to the corium
–White line ‘seals’ over Þ infection trapped = pus produced expands within potential space, under the sole = pain
–Usually abscesses form under the sole, occasionally infection tracks up the wall
•See only small black lines on the foot – trim and bursts out.
–Eventually pus breaks out, usually at heel or less commonly at the coronary band
What 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
What is this?
White line disease
What is this?
White line disease
What are the frequencies of white line lesions?
How do you diagnose white line disease?
–Pain if “tweak” claw
–White line impaction and abscess if trimmed and explored
–Small pin prick size holes to large areas of impaction on the white line (always black)
What can you see?
Small lesion of white line disease with draining pus
What is this?
Moderate sized white line lesion on abaxial wall
What is seen here?
Large white line
Large white line lesion on abaxial wall
What can be seen?
Large white line lesion on abaxial wall
What is this?
Same lesion trimmed out. A small area of necrotic corium is visible
What can be seen here?
Sub sole abscess breaking out at the heel
What is this?
White line lesion breaking out at the coronary band after tracking up the wall. Expose the whole track – but hard for horn to grow back
Get lesion to drain to prevent growing back!
No known specific treatment
How do we treat white line disease? (6)
–Trim and balance both claw
–Explore impacted white line, drain abscess (if present), remove under run sole (at least enough to prevent re-impaction)
–If tracked up wall, remove entire section of wall
–Antibiotic dressing? – 48 hours max
•Little evidence
–Foot block other claw if the lesion is extensive and administer NSAIDs
–Parenteral antibiotics may be necessary if necrotic corium is found
What is this and how is it used?
Occasionally antibiotic dressing are necessary to protect and treat extensive lesions. They should be removed after 48 hours and the other claw should be blocked
What is the prognosis of white line disease?
–Good – Simple sole abscesses respond well, however tracks up wall are more difficult to treat
–Occasionally deep digital sepsis as the result of infection spreading into deeper structures
What are the herd level risk factors for white line disease? (5)
- Periparturient increase in the movement of the pedal bone
- Lose of fat from the digital cushion?
- Poor underfoot conditions
- Presence of small sharp foreign bodies in the environment e.g. flint stones
- Turning sharply on concrete surfaces
What control measures do we have at a herd level for white line disease? (4)
- Improve cow tracks
- Improve underfoot conditions
- Reduce bullying and improve cow flow
- Addition of 20mg/cow/day of Biotin to the diet
What is the correct name for foul?
Interdigital Necrobacillosis
What is the aetiology of interdigital necrobacillosis?
- Acute necrotitising inflammation of interdigital skin
- Fusobacterium necrophorum +/- Secondaries (T. pyogenes, Streptococcus spp.)
- Damage to skin – FB’s, rough underfoot condition e.g. stubble, course straw
What are the clinical signs of foul? (7)
–Sudden onset moderate to severe lameness
–Swelling of soft tissues above and around the coronary band and between the digits (Digits forced apart)
–Swollen, hot, enflamed and painful
–“Split” in interdigital space which discharges pus and necrotic tissue. Infection invades in – looks as if its been cut
–Characteristic foul smell?
–Swelling may track higher up the leg as infection invades
–Anorexia, drop in milk yield, weight loss and pyrexia?
What is this?
Normal interdigital skin
What is this?
Mild “Foul” lesion
Necrotic tissue and looks split
What is this?
Mild foul lesion
What is this?
Moderate foul lesion – necrosis invading gap
What is this?
Extensive foul lesion
How do you treat foul? (6)
–Check interdigital space for FB’s
–Wash and flush with plenty of clean water
–Débridement necrotic tissue if present
–Apply topical antibiotics
–Parenteral antibiotics for 3-5 days
–Sulphamethoxypyridazine (Midicel), oxytetracyline (including LA), penicillin and penicillin / streptomycin combinations, tylosin (Tylan) and ceftiofur (Excenel, Zero milk withhold period)
What is the prognosis of foul?
–Good if treated early
–Deep digital sepsis can result in aggressive cases or if left untreated
–Worse if penetrating deep
What are the herd level risk factors for foul?
- Poor underfoot conditions
- Unhygienic underfoot conditions
What are the control measures on a herd level for foul?
- Improve underfoot conditions
- Foot bathing
What is super foul and how do we treat?
- 1993
- More aggressive and severe – invades super quick
- Quickly invaded the deeper structures of foot
- Early and aggressive therapy
- Clean, débrid and flush (IVRA?)
- Pack with antibiotic and bandaged (Clindamycin (Antirobe) capsules?)
- Systemic antibiosis (until signs resolve)
What is this?
Super foul
