Lecture 8 10/16/24

Question 1

What are enzootic nasal tumors?

Answer 1

tumors in sheep that expand from the turbinates and occlude the nasal passages

Question 2

What are the clinical signs of enzootic nasal tumors?

Answer 2

-copious serosangeunous nasal discharge
-facial deformity
-stertor/abnormal breath sounds

Question 3

What are the characteristics of enzootic nasal tumor transmission?

Answer 3

-associated with type D retroviruses
-retroviral genome inserts itself into host cell genome to alter the cell’s growth cycle

Question 4

How are enzootic nasal tumors diagnosed?

Answer 4

-imaging
-biopsy

Question 5

How are enzootic nasal tumors treated?

Answer 5

surgical debulking/resection

Question 6

How does Oestrus ovis cause damage?

Answer 6

larvae migrate through nasal passages and sinuses, inducing inflammation (rhinitis/sinusitis)

Question 7

How is Oestrus ovis diagnosed?

Answer 7

-sheep acting weird
-visualization of nasal bots

Question 8

What are the clinical signs of Oestrus ovis?

Answer 8

-mucopurulent nasal discharge
-abnormal breath sounds
-head shaking
-altered grazing behavior

Question 9

What are the characteristics of Oestrus ovis treatment?

Answer 9

-ivermectin twice a year
-treat once frost kills adults
-summer treatment prevents build up of excessive infestation
-treatment in winter prevents overwintering of larvae

Question 10

What is the most common type of retropharyngeal abscess?

Answer 10

caseous lymphadenitis

Question 11

Which bacteria causes caseous lymphadenitis?

Answer 11

Corynebacterium pseudotuberculosis

Question 12

What are the clinical signs of caseous lymphadenitis?

Answer 12

-inspiratory dyspnea
-dysphagia
-coughing
-ptyalism

Question 13

How is caseous lymphadenitis diagnosed?

Answer 13

-fine needle aspirate
-culture

Question 14

Why is it important to NOT drain caseous lymphadenitis abscesses?

Answer 14

increases risk of new infections

Question 15

What are the characteristics of caseous lymphadenitis treatment?

Answer 15

-no real treatment
-injection of formalin into abscess comes with a lifetime withdrawal
-euthanasia is common outcome

Question 16

Which viruses are associated with bacterial pneumonia in small ruminants?

Answer 16

-caprine/ovine herpesvirus
-caprine/ovine respiratory syncytial virus
-para-influenza 3 virus
-adenovirus

Question 17

What are the upper respiratory signs caused by viruses in small ruminants?

Answer 17

-nasal discharge
-cough
-pyrexia
-inspiratory dyspnea

Question 18

What is important to note regarding the diagnosis of resp. viruses in small ruminants?

Answer 18

there are very few specific diagnostic tests

Question 19

Which bacteria species cause bacterial bronchopneumonia in small ruminants?

Answer 19

-M. haemolytica
-P. multocida
-Bibersteinia trehelosi
-Mycoplasma spp.

Question 20

What are the clinical signs associated with bacterial resp. infections in small ruminants?

Answer 20

-fever
-depression
-dyspnea
-inc. lung sounds
-failure to thrive (chronic)

Question 21

What are the characteristics of Bibersteinia trehelosi?

Answer 21

-severe morbidity and mortality in big horn sheep
-typical bronchopneumonia in domestic livestock
-devastating, population limiting disease
-introduced to wild pop. through contact with domestic sheep and goats
-possible viral pathogen involvement

Question 22

What are the characteristics of Mycoplasma ovipneumoniae?

Answer 22

-only causes pneumonia, no systemic disease
-commensal organism of the nasal passages
-invasion of lower lungs causes consolidation and pinpoint abscesses
-high case attack rate, low case fatality rate

Question 23

What are the clinical signs of M. ovipneumoniae?

Answer 23

-mild disease
-mild chronic cough

Question 24

How is M. ovipneumoniae treated?

Answer 24

many of the antibiotics approved for M. bovis also work against M. ovipneumoniae

Question 25

Which Mycoplasma species are of importance in goats?

Answer 25

-M. mycoides ssp. mycoides
-M. capricolum ssp. capricolum

Question 26

What are the manifestations associated with Mycoplasma in goats?

Answer 26

-bronchopneumonia
-otitis media/interna
-septic arthritis
-mastitis
-septicemia
-pleuritis
-meningitis

Question 27

What are the characteristics of ovine progressive pneumonia and caprine arthritis encephalitis?

Answer 27

-retroviral, life long infections
-infect the macrophages/monocytes
-lentiviruses

Question 28

How are OPP and CAE transmitted?

Answer 28

-transfer of infected cells:
–colostrum/milk
–biting flies
–iatrogenic needles/shearing equipment
-respiratory secretions (OPP only)

Question 29

How do the clinical signs of OPP/CAE vary based on infected tissue?

Answer 29

lung: progressive loss of gas exchange
joints: synovial inflammation/loss of synovial fluid; arthritis
mammary gland: indurative mastitis
meninges: inflammation/damage to BBB leading to meningitis/encephalitis

Question 30

How does OPP manifest in adult sheep?

Answer 30

-2-5 years old
-chronic progressive weight loss
-interstitial pneumonia
-encephalitis
-mastitis
-arthritis

Question 31

How does CAE manifest in adult goats?

Answer 31

-2-5 years old
-progressive weight loss
-arthritis
-mastitis
-interstitial pneumonia

Question 32

How does CAE manifest in young goats?

Answer 32

-2-6 months old
-encephalitis

Question 33

How do the lungs appear on necropsy in OPP/CAE cases?

Answer 33

firm and unable to collapse

Question 34

What is important to note regarding OPP/CAE serology?

Answer 34

constantly changing virus induces a constant antibody response; infected animals are always positive on serology

Question 35

How often should antibody titers be tested for OPP/CAE?

Answer 35

twice a year

Question 36

What are the characteristics of test and cull for OPP/CAE?

Answer 36

-any positive animal is culled to prevent further transmission
-can be a large financial loss in herds with high prevalence

Question 37

What are the characteristics of test and segregate for OPP/CAE?

Answer 37

-positive animals are moved into a “dirty” herd
-infected and non-infected herds are maintained
-method breaks down easily due to difficulties in keeping herds separate

Question 38

What is the pathophysiology of ovine pulmonary adenocarcinoma?

Answer 38

infected cells have altered growth cycles due to retrovirus infection, resulting in transformation into neoplastic cells

Question 39

What are the clinical signs of ovine pulmonary adenocarcinoma in adult sheep?

Answer 39

-weight loss
-dyspnea
-cough
-copious nasal discharge when elevated by back feet