Musculoskeletal 1 Flashcards

1
Q

What are the two most common problems on a dairy farm?

A

Lameness

Mastitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Why is lameness important to the dairy industry?

A

Decreased milk production

Decreased reproduction
—15x more likely to have increased days open
— 8x more likely to be culled for repro failure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What clues should you look for when examining a cow for lameness?

A

Head bob

Limping or reluctance to bear weight

Hunched up back

Joints flexing unequally, or one more stiff than the other

Tracking up: rear feet should land almost in the foot prints left by the front feet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Where is lameness most commonly localized?

A

90% in the foot
Of that, 85% in the rear foot
Of that, 85% in lateral claw

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Where is hoof horn generated?

A

From dermis (corium)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the white line?

A

Dermal papillae of laminar corium that generates horn

=> softest horn, abaxial heel is softest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the rate of growth of the hoof wall?

A

5mm/month or 1/4 inch

About 1 year seen on a whole hoof

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the response of the corium to weight bearing?

A

Increased rate of horn production

Imbalance in weight bearing and overloading to the outside claw —> long toes and high heel —> increase risk to trauma to corium and higher risk for ulcer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Common conditions of the foot?

A

Interdigital phlegmon “foot rot”
Digital dermatitis
Heel horn erosion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Bacteria involved in foot rot?

A

Fusobacterium necrophorum

Porphyromonas levii

Prevotella intermedia

** anaerobic environment and tissue destruction with proteases and lukotoxins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the pathogenesis of foot rot?

A

Clot formation/local ischemia
— endotoxins and platelet aggregation

Protection from phagocytosis
Fusobacterium produces leukotoxin
P. Levii decreased optimizing antibodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How does foot rot impact the feeding period?

A

Decrease ADG of 0.05kg/day

14 additional days to finish

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the primary bacteria causing foot rot in small ruminants?

A

Dichelobacter nodosus (primary)

F necrophorum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the treatment for foot rot?

A

Debridement (bring air back to anaerobic bacteria)

Antibiotics

  • ceftiofur
  • oxytetracycline
  • florfenicol (nuflor)
  • gamithromycin
  • tilmucosin (mycotil)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

A market steer presents with foot rot 7 days before his last show. Which of the following treatment options is best?

A oxytet
B florfenicol
C Enrofloxacin
D ceftiofur

A

D ceftiofur

Withdraw time is less than 7 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Infectous foot rot in sheep is best treated by?

A enrofloxacin
B procaine pen G
C gamithromycin
D tilmucosin

A

C gamithromycin works the best against anaerobes

PPG also would work against anaerobies but not as good

17
Q

Digital dermatitis is AKA ?

A
Hairy heel warts 
Strawberry foot 
Verrucous dermatitis 
Digital warts 
Interdigital papillomatosis
18
Q

EDx of digital dermatitis?

A

Treponema spp (spirochetes)

19
Q

What environmental conditions predispose to digital dermatitis?

A

Confinement
Excess manure
Increased standing due to poor stalls or over crowding

20
Q

Treatment for digital dermatitis?

A

Oxytet (topical or systemic)

Footbaths

  • copper sulfate >5% solution
  • formalin
21
Q

What are common causes of heel horn erosion?

A

Poor environmental hygiene

Bacterial degradation of heel horn

22
Q

What causes loss of heel horn?

A

Claw instability

Weight sift

Ulcer develop

23
Q

What causes thin soles?

A

Rate of growth < rate of wear

Eg wet rough concrete or increased standing time

Excess trimming
During early lactation, hoof growth rate is decreased

24
Q

What is the sequelae to thin soles?

A

Damage to sole corium
- toe ulcers or sole ulcers

White line dz

  • less mature horn exposed
  • more susceptible to foreign material penetration
25
Q

Where are the most common locations for solar ulcers to occur in ruminants?

A

Lateral claw of hind foot

Medial claw of fore foot

26
Q

What is the most common indication of a sole ulcer, besides lameness

A

Hemorrhage

27
Q

What is white line disease?

A

Inflammation, ischemia of laminar corium

Often caused by shearing and compressive forces of P3

Increased rate and decrease quality horn growth —> fissure cracks

28
Q

What occurs in subclinical laminitis?

A

Claw horn integrity compromised

Suspensory apparatus compromised

  • collagen connecting P3 to lamellae
  • digital cushion —> cruciate ligaments affected at attachments
29
Q

Why does the toe tip up in laminitis ?

A pushed away from P3 by blood
B increased goth of dorsal hoof
C extensor tendon pull
D increased heel growth

A

D increased heel growth

30
Q

Common causes of laminitis in cattle?

A

Dairy

  • mastitis and metritis
  • lactation ration

Beef
-feedlot

Rumen acidosis

31
Q

Treatment of laminitis?

A

Acute — NSAIDS or euthanasia

Chronic — hoof trim and diet

32
Q

What is the pathogenesis of laminitis?

A

Vasoactive compounds result in decreased blood flow —> ischemia, edema, pressure, and epidermal damage

Laminar corium damaged — P3 sinks and compresses sole corium

Generalized damage — increased rate and decreased quality of horn production

33
Q

What role do cytokines play in laminitis?

A

Acute grain overload increases IL-1 in hoof laminae

MMP present in normal hoof for remodeling but may be out of control in laminitis (activated by cytokines, ROS, and NO)
—> can be increased at calving

34
Q

How much laying time should a cow have per day??

A

10-12 hours

35
Q

What is the ideal stall surface material?

A

Sand
Composite

Rubber filled mattresses?

DRY!

36
Q

T/F: cows prefer to walk and stand of soft surfaces

A

True

Rubber mats in walkways

37
Q

What type of foot baths are available to treat hoof disease?

A

Copper sulfate (5-10% solution)

Zinc sulfate

Formalin (2-5% solution) — formalin is cheap but less safe

38
Q

What is often the only sign of solar trauma?

A

Discolouration of solar horn overlying point of entry