Lameness Flashcards
what causes a swinging leg lameness?
pain when bringing the leg forward
are most upper limb lamenesses swinging or weightbearing?
mainly swinging (shortened forward stride)
which leg has a shortened stride when an animal has a weight bearing lameness?
shortened is on the good leg
how does the head position change at the point of weight bearing on a lame leg?
if lame on front leg - head up
if lame on back leg - head down
what is the use of a flexion test?
exacerbate the lameness in the joint that is held in flexion
what can cause atrophy of muscle associated with lameness?
disuse - pain
neurological
what are some possible theories about the causes of tight tendons in calves?
position in utero
manganese deficiency
hereditary
what are some options for treating tight tendons in calves?
cast
metal splint
tendonectomy
what is the main differential for arthrogryposis?
schmallenburg
what can cause gastrocnemius ruptured?
rotational force (foot stuck)
sudden weight
trauma
weakening/compartment syndrome
hypophosphataemia
what causes a similar stance to gastrocnemius rupture in cattle?
tibial nerve paralysis
what is the most common cause of flexor tendon injury in cattle?
trauma (then infection) - usually an open contaminated wound
why is it useful to cast an open wound to the leg after infection in controlled?
highly mobile joints that will pull wound edges apart whenever they walk
how should cellulitis on the limb be treated?
aggressively with antibiotics and anti-inflammatory
how does a cow with patellar fixation present?
intermittent lameness and wear of dorsal horn
what is the treatment for patellar fixation?
cut medial patellar ligament near distal end on both legs (not on the same visit - other with usually develop it as well)
what is the main cause of peroneus tetras rupture?
pulling leg two high up (foot trimming)
what causes a flying scapula?
serrautus ventralis rupture
what are the osteodystrophies seen in cattle?
rickets - young growing cattle
osteoporosis and osteomalacia - adult
what causes osteodystrophies in cattle?
calcium, phosphorous, copper deficiency
rapid growth, gender, genetics, housing
why are oesteodystrophies more common in beef animals?
tend to be fed homegrown diet which doesn’t have the correct minerals and they grow rapidly
what are the clinical signs of osteodystrophies?
stiffness/recumbency
bone distortion
long bone fractures
swelling joints/epiphysis
what causes white muscle disease?
vitamin E and selenium deficiency
what breeds are predisposed to hip dysplasia?
herefords, angus, galloways, Limousin, charolais
what are the main points osteochondrosis occurs in cattle?
atlanto-occipital joint
femora-patellar joint
how does degenerative joint disease present?
progressively lame animal in young/growing cattle
how does the direction of hip dislocation effect how the animal presents?
cranio-dorsal displacement - walking
cause-ventral displacement - recumbent
what is a common cause of metacarpal/tarsal fractures?
calving ropes during assisted delivery
when should box rest only be considered in fracture cases?
no displacement or joint involvement
animal is ambulatory
why does care need to be taken using xylazine to sedate calves?
large drop in cardiac output
what are some possible complications of fractures?
osteomyelitis
dislocation/non-union
decreased bone development
ischaemic necrosis
nerve damage
disuse atrophy
what are the two ways haematogenous arthritis can occur?
haematogenous spread
traumatic
what is the most common pathogen that causes septic arthritis?
Truperella pyogenes
what is done to diagnose septic arthritis?
arthrocentesis - high protein and nucleated cell count
what are the main non-infectious causes of lameness in the foot?
sole haemorrhage/bruising
sole ulcers
white line lesions
what is sole haemorrhage?
contusion of the corium due to pressure from the pedal bone and external pressure
what causes double sole formation?
complication of sole haemorrhage/bruising
what is a sole ulcer?
more severe manifestation of sole haemorrhage/bruising leading to disrupted sole horn production and corium exposure
what are the key anatomical features of the foot that play a role in sole haemorrhage/ulcers formation?
pedal bone
digital cushion
corium/sole
what is the treatment for sole haemorrhage/ulcers?
functional trimming
block unaffected claw
NSAIDs
what is the white line?
area where hoof wall meets the sole (weak point_
what is white line disease?
separation at the white line due to external pressures and sideways forces
how is white line disease treated?
functional foot trimming and removal or detached horn
block unaffected claw
NSAIDs
(antibiotics? - abscess)
what structure defines the lying and lunging area of a cubicle?
the brisket board
what is the best choice of bedding for cubicles from a lameness aspect?
deep sand bedding with mats
what behaviour does overstocking lead to?
increased standing times
more aggressive interactions
how much resting area is needed per cow in a straw years?
at least 10 square metres
how much feed barrier space should a cow have?
at least 70cm
what factors effect cow comfort?
cubicle space/bedding
feed barrier space
milking frequency/duration
floor surfaces and tracks
cow flow - sharp turns, handling…
animal handling
what is a possible issue with having rubber flooring all over a shed?
cows don’t lie in cubicles and lie on rubber flooring instead - mastitis risk
what areas of the farm could rubber flooring be used for?
high cow flow areas - exit to parlour, collecting yard…
how do overgrown claws effect the pedal bone?
rotates the pedal bone and puta more pressure on the soft tissue
what is a major risk period for sole haemorrhage/ulcers and white line disease?
just after calving (foot trimming 50 days after calving)
how thick should you trim the sole to be?
5-8mm
why is calving a risk factor for lameness?
causes weakening of the connective tissue of the claw suspensory apparatus (lamellae)
what is the cause of increased laxity of the suspensory apparatus of the claw around calving?
hormonal changes around calving
other than hormonal changes, what else contributes to increase lameness risk after calving?
bullying, new housing, new diet…
what is the correlation between lameness and BCS?
lame cows are thinner (lameness a risk factor for low BCS and low BCS is a risk factor for lameness)
what is the role of the digital cushion?
to protect the corium and epithelium
how is the digital cushion effected around calving?
it is thinner post calving
(also thinner in first lactation animals)
what age of cow (lactation) has the thinnest digital cushion?
first lactation is significantly thinner - adding to lameness susceptibility
how does age effect the likelihood of becoming lame?
older cows more likely to be lame - once they have had a lesion they are more likely to get it again
how does nutrition effect lameness?
SARA
deficiencies (biotin…)
BCS
why are transition cows at risk of lameness?
reduced DMI and fat mobilisation
calving effects
diet changes
comfort changes - bullying, feed space…
how can heat stress effect lameness?
heat stress causes cows to stand up for longer in cooler places
what temperature do cows get heat stress?
> 25 degrees with high humidity
what factors of genetics effects lameness?
foot angle
milk yield
digital foot pad thickness
what causes interdigital hyperplasia?
chronic skin irritation
how is interdigital hyperplasia treated?
surgical removal if painful/infected (anaesthesia possibly needed)
what is the major risk factor for toe necrosis?
over wear/trimming of toe sole
how can toe necrosis be treated?
trim and block
partial/full digital amputation
what is another name for a vertical wall crack?
sand crack
how are vertical wall cracks treated?
trim and block
stabilise the hoof wall
complications of what can lead to deep digital sepsis?
untreated foul in the foot
complicated sole ulcers
untreated white line abscesses
what can be done to treat deep digital sepsis?
amputation, arthrodesis or euthanasia
what is corkscrew claw?
the dorsal edge of the claw wall deviates from a straight line (often hereditary)
what are the indications for digit amputation?
deep digital sepsis
retroarticular abscess
non-healing wall lesions
toe necrosis
what are the methods of digit amputation?
disarticulation of proximal interphalangeal joint
cut through P1
cut through P2
what method of digit amputation has the worst outcome?
cutting through P2 - leave a small portion of P2 which can cause complications
what type of nerve block is used for digit amputation by disarticulation?
IV regional block (tourniquet required)
how should a digit amputation be managed post surgery?
NSAIDs and antibiotics
bandage and block
put in clean environment
what is the main piece of equipment used for digit amputation when you cut through P1?
embryotomy wire
what is the aim of arthrodesis?
save both claws but address/treat the deep joint damage in the foot - destroy and fuse the joint
what type of anaesthetic is used for arthrodesis?
IV regional block (tourniquet required)
what are the steps of arthrodesis?
block and surgically prepare
remove navicular bone
flush/destroy joint
place drains
what is the major advantage of arthrodesis over digit amputation?
2 claws left so may last in herd longer
what are the main infectious foot disease of cattle?
digital dermatitis
interdigital phlegmon (foul in the foot)
interdigital dermatitis
heel horn erosion
what are some other names for digital dermatitis?
mortellaro disease
hairy heel warts
strawberry foot
what is the main bacteria involved in digital dermatitis?
Treponema spp. (spirochete)
what are the main Treponema spp. associated with digital dermatitis?
Treponema denticola
Treponema medium
Treponema phagedenis
how would the lesions of digital dermatitis be described?
painful reddened area just above the interdigital cleft between the heel bulbs (usually with erected hair around the lesions)
what are the stages of digital dermatitis?
M0
M1
M2
M3
M4
M4.1
what is a M0 digital dermatitis lesion?
normal digit with no signs of lesion
what is a M1 digital dermatitis lesion?
early small lesion less than 2cm that is circumscribed and red/grey in colour
what is a M2 digital dermatitis lesion?
acute active ulcerative or granulomatous lesion greater than 2cm in diameter
what is a M3 digital dermatitis lesion?
acute healing lesion covered by a firm scab
what is a M4 digital dermatitis lesion?
chronic lesion that can be dyskeratotic or proliferative
what is a M4.1 digital dermatitis lesion?
chronic lesion with subacute components (reactivated lesion)
what is found on top of the epidermis of cows feet?
microbiome (has a role to play in development of digital dermatitis)
what are potential entry points of Treponemes into the skin to lead to digital dermatitis?
skin damage/integrity
hair follicles
sebaceous glands
what are some risk factors for the development of digital dermatitis?
exposure to slurry and wet conditions
grooved flooring - skin integrity/cleanliness??
infected cows
poor hygiene
foot trimmers/biosecurity
buying in animals
stocking density
genetics
how long can treponemes causing bovine digital dermatitis survive on foot trimming equipment?
can be alive for over 2 hours
why is stocking density a risk factor for digital dermatitis?
overcrowding causes increased standing time so more time stood in slurry and damaging skin integrity
how does parity effect digital dermatitis risk?
young cows have increased risk and this often becomes chronic in infected cows
how can digital dermatitis be controlled?
improve conditions and risk factors
screening and early treatment
genetic selection
footbathing
what is the main source of digital dermatitis infection?
chronically infected cows
when is a good time to screen and detect early digital dermatitis lesions?
in the parlour
what are some possible footbath solutions for digital dermatitis control?
copper sulphate
formalin
zinc sulphate
what is the issue with using copper sulphate footbaths?
damaging to the environment when disposed of
what are some important aspects to consider when using footbaths?
feet should be as clean as possible
change solution at appropriate intervals
correct concentration
correct contact time for solution
how often should cows be footbathed for digital dermatitis control?
multiple times a week
how should early stage lesions of digital dermatitis be treated?
clean/dry lesion
apply topical antibiotics (oxytetracycline)
keep in a clean dry environment for a few days
should digital dermatitis lesions be wrapped?
no - no evidence to support this and gives a damp dirty environment for the lesions
are NSAIDs indicated for digital dermatitis?
yes - animal is painful (decreases severity of lameness) (NSAIDs indicated for any lameness)
what is the blitz approach digital dermatitis treatment and why is it useful?
screening entire herd and simultaneously treating all active/recurring lesions with improved hygiene and footbathing protocols this reduces infection pressure to control outbreaks
what is foul in the foot also known as?
foot rot (USA)
interdigital phlegmon
interdigital necrobacillosis
infectious pododermatitis
what is the main bacteria responsible for foul in the foot?
Fusobacterium necrophorum
what is the clinical presentation of foul in the foot?
diffuse swelling above the claw with characteristic necrotic odour that begins in the interdigital space
acute onset and very painful
what is done to treat foul in the foot?
early intervention is crucial
clean lesion and remove necrotic tissue
systemic antibiotics and NSAIDs
what systemic antibiotics can be used for foul in the foot?
oxytetracycline
pen and strep
tylosin
ceftiofur (avoid as is critically important)
what is interdigital dermatitis?
mild infection of the interdigital space that can spread across the heels causing horn erosions
what is the main bacteria associated with interdigital dermatitis?
Dichelobacter nodosus
how can foul in the foot be differentiated from interdigital dermatitis?
foul with have diffuse swelling and pain
what is heel horn erosion?
progressive destruction of the heel horn associated with poor hygiene (not very painful)
what is done to treat heel horn erosion?
foot trimming and topical antibiotics if needed
what is pain?
unpleasant sensory and emotional experience caused by actual/potential tissue damage
what are some indicators a cow is in pain?
reduced activity and increased lying
changing posture (less load on foot)
increased HR and RR
decreased food intake, body weight and rumen turnover
facial expression
what are some indicators a cow is in pain?
reduced activity and increased lying
changing posture (less load on foot)
increased HR and RR
decreased food intake, body weight and rumen turnover
facial expression
how may a cows posture indicate pain?
reduced weight bearing
spine arched
hanging/nodding head when walking
shuffling walk
shortened stride
what are the three levels of welfare protection for animals on farms?
legislation
welfare code
farm assurance schemes
