Cattle Lameness Flashcards
Why should we bother with lameness?
It is a SIGN (not disease) that is a huge welfare concern. Affects all 5 freedoms and is v prevalent.
Which cows are more likely to get lame?
what does this mean?
High yielding cows more susceptible to lameness
this means you may have a cow producing more than average however for her individually is a loss
A HPC lame could cost you 500-600 kg milk
Pressures on the farmer to tackle lameness
- public perception
- Costly - treatment, cull, reduced milk yield
- Impacts repro performance
How does cattle lameness affect repro? (6)
- Delayed cyclicity
- associated with Ovarian cysts
- Don’t show heat as well (pain) won’t want to mount!
- Longer to conceive = prolonged calving intervals
- Less likely to ovulate when manipulate with hormones as well
- lower oestrus intensity
- lower progesterones levels before oestrus
How does cattle lameness affect repro? (6)
- Delayed cyclicity
- associated with Ovarian cysts
- Don’t show heat as well (pain) won’t want to mount!
- Longer to conceive = prolonged calving intervals
- Less likely to ovulate when manipulate with hormones as well e..g doesn’t respond as well to progesterone synchronisation regime
- lower oestrus intensity
- lower progesterones levels before oestrus
What impact does lameness have on nutrition
- reduced time spent eating
- reduced dry matter intake
- Low BCS, low milk production
Cost of lameness
treatment - drugs, vet, milk withdrawal Labour Reduced milk yield Reduced repro performance involuntary culling Low carcass quality
Why do farmers often miss lame cows
Only really lame identified that are obvious/ staying at the back
How can we help farmers assess lameness?
- Regular mobility scoring
- lesion recording
- Hock Assessment Scoring 1-3
How can we help farmers assess/ measure lameness?
- Regular mobility scoring (0-3)
- lesion recording
- Hock Assessment Scoring 1-3
Good way to help farmers change
Give them numbers:
40% of your cows lame. Aim = 20% for e.g.
Mobility scoring numbers and aim
0, 1, 2, 3
Aim = deal with score 1 and 2 to PREVENT ever getting to score 3
Just dealing with 3 won’t get you anywhere
Signs of lameness cow
Head bob, shorten stride, arches back
What does hock assessment t indicate?
High score (3) indicates environment isn’t very comfortable = predisposing factor to lameness
What are lameness mostly due to?
Foot lesions
of which we have infectious and non infecitous
Infectious causing lesions include
- Digital dermatitis
- Foul in the foot
- Interdigital dermatitis
- heel horn erosion
Non infectious causing lesions include
- Sole haemorrhages/ bruising
- Sole ulcers
- white line lesions
biomechanics of foot growth
Continuous growth of horn and continuous wear
What causes problems wrt foot wear?
When do you get XS wear?
More growth than wear = claw overgrowth which leads to issues
XS wear if abrasive concrete, walking long distance = thin sole = diff problems
Most problem with housed herds on concrete = growth faster than wear
Problems more prominent in hind feet
More exposed to slurry
Forelimbs attached to body by more elastic components
More forgiving
Lateral claws of hind feet progressively outgrow medial ones = where cow distributes more weight and when more G than W, initial inc weight distribution on lateral gets exacerbated = produces more horn = more pressure in coreum between pedal bone and sole In lateral claw
The solar dermis is under pressure between the pedal bone and the sole
Heal lateral claw hits ground first = more weight, pressure = overgrows
Describe 5 stage Dutch method
Assume lateral hind overgrowth
Start with medial hind claw (lateral fore) (won’t need as much work.
Measure toe length: from where coronary bad goes hard to tip of toe
Trim dorsal wall length to 7.5-8 cm (9 for large Holsteins?)
Where do we measure?
Sticking to this cm can be problematic as not 1 size fits all. Adapt to cow. Huge cow = probs a bit more!
If over trim and go too short you will hit the soft tissue, bleed cow, pain
Means sole cut too short = predisposed to lesions
Leave a bit more than over trim!
Reduce sole depth at the toe to approximately 5 to 7 mm (don’t over trim)
Spare the heel
Heal depth is important- for lesions and dermatitis!
Correct wall length/ sole depth of the other claw
Model/ dish out
deeper and wider modelling of the lateral hind/medial fore claw (Dairyland, some supporting evidence)
Hock assessment: explain them so in exam can look at a pic and say what it is
1 = no swelling. no hair missing
2 = no swelling, bald area on hock
3. Swelling evident and lesion through hide
What anatomical structure is very important in development of lameness causing lesions?
Pedal bone, especially the tuberculum flexor process
Why?
Rotation of it can impinge on soft tissue
Aim of foot trimming
keeping pedal bone in correct anatomical position
Importance of Digital cushion
= bit of tissue like a pad, mostly fat and connective tissue, has some protective functions for foot. Mainly protecting the soft tissue that is just under the pedal cushion – part producing healthy keratinocytes, ending up forming ahrd aprt of sole that is protecting the softer tissues
What is the suspensory apparatus of the digit?
Collagen fibres keeping pedal bone attached to dermal lamellae
Extremely important in cattle lameness
