Neurological Causes of Musculoskeletal Disease in Ruminants

Question 1

What is neurological lameness most closely associated with? How is it treated?

Answer 1

TRAUMA or estrus

quick administration of NSAIDs (> 12 hr can be too late)

Question 2

What is indicative of spinal abscesses?

Answer 2

dog-sitting + knuckling = losing function of rear end, lacking feeling and ability to pass manure; subtle lameness can look like rabies

• more common in calves

Question 3

What are 4 common causes of peripheral nerve disorders?

Answer 3

1. prolonged lateral recumbency
2. dystocia (calf AND cow)
3. injections of Tetracycline
4. fractures

Question 4

What is the brachial plexus? What is a common cause of trauma?

Answer 4

network of nerves controlling movement and sensation in the forelimb

forceful pulling or stretching of forelimb

Question 5

What are the 2 presentations of radial nerve paralysis based on injury?

Answer 5

1. higher up = whole limb unable to support weight
2. lower = can support weight, flops foot forward when walking

Question 6

What is indicative of obturator and sciatic nerve damage? How do they compare?

Answer 6

back legs splay out, forcing the cattle into recumbency

SCIATIC = more severe, likely unable to get up

Question 7

How can further damage to obturator/sciatic nerves be avoided?

Answer 7

proper footing + hobbles

• concrete can become slick, especially in dairies

Question 8

What nerve is likely damaged?

a. obturator
b. peroneal
c. radial
d. sciatic
e. tibial
f. whole spinal cord

Answer 8

A, D

Question 9

What nerves are commonly affected by dystocia?

Answer 9

• obturator
• sciatic
• tibial

consider cow AND calf

Question 10

What is indicative of tibial nerve injury?

Answer 10

dropped hock and knuckled fetlocks on hindlimb of adult cattle

Question 11

What is indicative of peroneal nerve injury?

Answer 11

knuckling causes calf to walk on pastern or fetlocks on hindlimbs

• NO dropped hock

Question 12

What nerve is likely damaged?

Answer 12

tibial - adult cow, flexed fetlock with dropped hock

Question 13

What cattle is most commonly affected by femoral nerve injury? How do they present?

Answer 13

calves with history of pulling (dystocia, trauma)

hunched/crouched appearance

Question 14

What nerve is likely injured?

Answer 14

femoral - calf, hunched

Question 15

What nerve is affected?

Answer 15

tibial

• dropped hock
• flexed fetlock

Question 16

What neve is likely affected?

Answer 16

radial

• likely lower, some weight bearing seen

Question 17

What commonly causes staggers in cattle? When is this most commonly seen?

Answer 17

Dallisgrass - invasive growth in pasture

not common in winter - plant dies —> late spring into fall allowing for time for the seed heads to grow

Question 18

How is Dallisgrass Staggers treated?

Answer 18

• remove dallisgrass from pasture
• move individuals into a different pasture with mized forage (dilutes toxin ingestion)

should recover in a few days

Question 19

A cow has a history of dystocia and has been noted to have splayed hindlimbs. Following lifting in a water rising system, she regained use of the limbs. What nerve was likely affected?

Answer 19

obturator —> splayed, able to get up and weight bear

• sciatic would be much more severe, unlikely to get up

Question 20

What breed of cattle is commonly affected by progressive ataxia? How long does this typically take to occur?

Answer 20

Charolais - recessive defect

between 6 months to 3 years old

Question 21

What are the 2 most common clinical signs associated with progressive ataxia of Charolais? What treatment is available?

Answer 21

1. progression from slight incoordination to downer status
2. abnormal urination, esp females

NONE (confirmed by histopath)

Question 22

What breed of cattle is most commonly affected by Weaver syndrome? What sign is most common?

Answer 22

(progressive degenerative myelencephalopathy)

Brown Swiss

hindlimb ataxia with a weaving gate, commonly appearing around 6-8 months and progressing to inability to rise

Question 23

How do cows with spinal LSA present?

Answer 23

crouched, knuckling, 3 legged lameness

(common during parturition)

Question 24

What parasite is associated with spinal lesions? Why must they be carefully treated?

Answer 24

Hypodermal bovis (H. lineatum migrates toward diaphragm and esophagus) —> sudden or acute downers

part of life is in the spinal cord and killing them can cause an inflammatory reaction

Question 25

In what species is spinal fracture and trauma common?

Answer 25

cria —> young llamas

Question 26

What nerve is likely affected?

a. obturator
b. peroneal
c. radial
d. sciatic
e. tibial

Answer 26

B

• knuckling without dropped hock