Neurologic Diseases of Ruminants

Question 1

which cranial nerves are involved in the menace response?

Answer 1

cranial nerves II and VII

Question 2

what causes cerebellar hypoplasia?

Answer 2

pestivirus
BVDV in cattle
border disease virus in small ruminants

Question 3

what is the incubation period of rabies?

Answer 3

3 weeks to 6 months

Question 4

what is polioencephalomalacia?

Answer 4

necrosis of the grey matter

Question 5

what are the signs of polioencephalomalacia?

Answer 5

cerebral signs:
star-gazing
altered mentation
blindness with intact PLR

Question 6

what are the risk factors for thiamine deficiency?

Answer 6

hypo/anorexia
poor roughage diet
ingestion of thiaminases

Question 7

what does excess sulfur inhibit?

Answer 7

mitochondrial electron transport chain

Question 8

what can be seen on a blood smear with lead toxicity?

Answer 8

anemia with RBC basophilic stippling

Question 9

what are the common causes of salt toxicity?

Answer 9

inappropriate milk replacer without free choice water
high salinity well water/softeners
inaccessible water sources

Question 10

what are the clinical signs of hypomagnesemia?

Answer 10

aggression
seizures
facial twitching

Question 11

what are the three important mechanisms of bacterial meningoencephalitis?

Answer 11

general sepsis associated
Histophilus somni associated thromboembolic meningoencephalitis
Chlamydophila pecorum biotype 2

Question 12

what is the pathophysiology of bacterial meningoencephalitis Histophilus somni?

Answer 12

part of bovine respiratory disease complex
thromboembolic vasculitis- polyserositis

Question 13

what is mad cow/transmissible spongiform encephalopathies/prion?

Answer 13

bovine spongiform encephalopathy

Question 14

is Listeriosis zoonotic?

Answer 14

yes

Question 15

how is vitamin A derived?

Answer 15

from fresh green grass and stored in liver

Question 16

how can you diagnose Parelaphostrongylus tenuis?

Answer 16

neurologic deficits localizing to spinal cord, can be anywhere
CSF show eosinophilic pleocytosis 50% of timee

Question 17

what is radial nerve paralysis commonly due to?

Answer 17

prolonged recumbency, falls, or restraint injury

Question 18

what is the most common peripheral nerve injury?

Answer 18

sciatic nerve

Question 19

what is the brainstem involved in?

Answer 19

arousal

Question 20

what is the thalamocortex involved in?

Answer 20

behavior: mental status, menace response, nasal septum tactile response

Question 21

what is involved in the menace response?

Answer 21

cranial nerve II
cortex
cerebellum
cranial nerve VII

Question 22

what is involved in the pupillary light reflex?

Answer 22

cranial nerve II
cranial nerve III

Question 23

what is involved in position of the eye in the orbit and eye movement?

Answer 23

cranial nerve III, IV, VI

Question 24

what is involved in physiologic nystagmus?

Answer 24

cranial nerves III, IV, VI, VIII

Question 25

what is involved in palpebral reflexes?

Answer 25

cranial nerve V, VII symmetry of the face: cranial nerve VII

Question 26

what is involved in food prehension?

Answer 26

cranial nerve XII masticatory movement: cranial nerve V

Question 27

what is involved in dysphagia and laryngeal problems?

Answer 27

cranial nerve IX and X

Question 28

how can you diagnose cerebellar hypoplasia?

Answer 28

cerebellar ataxia, nystagmus pre-colostral antibody titers for BVDV blood, skin, tissue antigen- false negatives possible necropsy

Question 29

how can you prevent cerebellar hypoplasia?

Answer 29

test and remove clinically affected neonates BVDV vaccination of dams biosecure management

Question 30

what is cerebellar abiotrophy?

Answer 30

born normal and cerebellum atrophies at <1 year of age

Question 31

what is cerebellar hypoplasia?

Answer 31

cerebellum incompletely developed from birth

Question 32

how can you diagnose rabies?

Answer 32

identification of negri bodies or IFAT on CNS tissue

Question 33

what are the four etiologies of polioencephalomalacia?

Answer 33

thiamine deficiency sulfur toxicity lead toxicity salt toxicity

Question 34

what supplies thiamine to ruminants?

Answer 34

rumen microbes

Question 35

what is the prognosis of thiamine deficiency?

Answer 35

good if treatment initiated early

Question 36

what are the sources of excess sulfur?

Answer 36

well contamination feeding sugar by-products

Question 37

how can you diagnose sulfur toxicity?

Answer 37

identify high sulfur source in feed rumen gas cap hydrogen sulfide often low post-mortem changes are identical to thiamine deficiency or polioencephalomalacia

Question 38

how can you treat sulfur toxicity?

Answer 38

thiamine supplementation supportive care

Question 39

what is the pathophysiology of lead toxicity?

Answer 39

lead interferes with calcium signaling and multiple enzymes requires for ATP production

Question 40

how can you diagnose lead toxicity?

Answer 40

whole blood levels reliable radiographic lead lines blood smear changes

Question 41

how can you treat lead toxicity?

Answer 41

thiamine supplementation supportive care EDTA administration to chelate lead

Question 42

how can you treat salt toxicity?

Answer 42

thiamine supplementation supportive care slow correction of hyponatremia dextrose and isotonic sodium bicarbonate

Question 43

what can cause metabolic cerebral disease?

Answer 43

nervous ketosis hypomagnesemia

Question 44

how can you prevent bacterial meningioencephilitis from Histophilus somni?

Answer 44

vaccine oxytetracycline metaphylaxis on feedlot

Question 45

how can you diagnose transmissible spongiform eencephalopathies- bovine?

Answer 45

histologic of immunohistochemical evaluation of the OBEX for abnormal protein aggregates and histologic changes

Question 46

is transmissible spongiform encephalopathies- scrapie- associated with feeding practices?

Answer 46

no

Question 47

is ante-mortem biopsy of peripheral lymphoid tissue diagnostic of scrapie?

Answer 47

yes- affected protein accumulates throughout lymphoid tissues of body

Question 48

what are the parasitic cerebral diseases?

Answer 48

nervous coccidiosis coenurus cerebralis Parelaphostrongylus tenuis

Question 49

what are the main brainstem/cranial nerve diseases?

Answer 49

listeriosis otitis interna vitamin A deficiency

Question 50

is Listeriosis zoonotic?

Answer 50

yes

Question 51

how can you diagnose Listeriosis?

Answer 51

CSF mononuclear pleocytosis and elevated protein post-mortem: micro-abscesses

Question 52

which antibiotics do not work on Listeriosis?

Answer 52

cephalosporins

Question 53

how can you prevent otitis media/interna from M. bovis?

Answer 53

minimize respiratory disease in calves milk/colostrum management: feed only commercial or pasteurized colostrum and milk

Question 54

what is vitamin A important for?

Answer 54

bone, retinal, epithelial metabolism

Question 55

why does blindness occur with vitamin A deficiency?

Answer 55

blindness due to retinal degeneration and compression of the optic chiasm due to boney hyperplasia

Question 56

what is spinal lymphosarcoma often from?

Answer 56

BLV-associated

Question 57

how can you treat Parelaphostrongylus tenuis?

Answer 57

high dose fenbendazole supportive care monthly ivermectin