Respiratory conditions

Question 1

Signs of upper respiratory infection

Answer 1

Stridor
Sneezing
Nasal discharge
Increased resp rate
Coughing
Referred abnormal lung sounds

Question 2

Signs of lower respiratory infection

Answer 2

Extension of neck
Elbow abduction
Nasal discharge
Increased resp rate
Coughing
Abnormal lung sounds (CV)
Exercise intolerance
Dyspnoea

Question 3

Causes of URT disease (6)

Answer 3

• Nasal myiasis
• Laryngeal chondritis
• Nasal foreign bodies
• Nasal tumours:
  Adenopapillomas or polyps
  Squamous cell carcinomas - adenomas
  Adenocarcinomas

Question 4

Nasal myiasis

Answer 4

Larval form of the sheep bot fly (oestrus ovis)
Infects nasal passages and sinuses
Can last 1-10 months, leave by being sneezed out by dropping to ground
Reduction in grazing, loss of condition, may stamp their feet or shake their head, sheep congregate in a circle with heads in the centre. May be neurological signs
Movement induces profuse clear and mucoid nasal discharge
Treat with a single doing of Ivermectin (ML)

Question 5

Pharyngeal trauma

Answer 5

Commonly from overly aggressive use of bolusing guns
May result in abscesses or extensive and diffuse cellulitis of the soft tissues
Signs: impaired swallowing, inappetance, secondary loss of condition

Question 6

Laryngeal chondritis

Answer 6

Usually seen in meat breeds
Laryngeal cartilages become inflamed and oedematous
Marked respiratory effort, inspiratory dyspnoea and stridor
Neck extended, head held lowered with flared nostrils and mouth open
PM appearance is diagnostic - necrosis with purulent exudate
Treat with penicillin, corticosteroids and NSAIDs, maybe an emergency tracheotomy
Very guarded prognosis

Question 7

Ilex choke

Answer 7

Sudden death or acute choke
Reported in lambs that have holly or ilex leaves obstructing pharynx

Question 8

Common causes of viral pneumonia

Answer 8

Parainfluenza virus type 3
Ovine adenovirus

Question 9

Common causes of viral respiratory disease

Answer 9

Maedi-visna
Ovine pulmonary adenocarcinoma (Jaagsiekte)

Question 10

Common causes of bacterial pneumonia

Answer 10

Manheimia haemolytica
Bibersteinia trehalosi
Pasteurella multocida
Mycoplasma ovipneumoniae

Question 11

Most common cause of parasitic pneumonia

Answer 11

Dicyocaulus filaria

Question 12

Clinical signs of acute viral pneumonia

Answer 12

Mild respiratory signs
Not always pyrexic
Cough
Serous nasal discharge
Conjunctival discharge
Usually not lethal
Can lead to secondary bacterial infections

Question 13

Diagnosis of acute viral pneumonia

Answer 13

Often unnoticed until more chronic
PM
BAL/transtracheal washes
PCR

Question 14

Treatment of acute viral pneumonia

Answer 14

Antibiosis to prevent bacterial overgrowth
NSAIDs

Question 15

Pasteurellosis

Answer 15

Two main syndromes
- Pneumonic form: acute, exudative, necrotising pneumonia. Frequently fatal, often M. haemolytica is isolated
- Systemic form: acute, fatal disease- often Bibersteinia is isolated

Question 16

Clinical disease of pasteurellosis

Answer 16

Four different presentations
- Septicaemia and sudden death (birth to weaning)
- Pneumonia (older lambs)
- Mastitis
- Joint ill in lambs

Question 17

Clinical signs of pneumonic pasteurellosis

Answer 17

Acute pneumonia from about 2 months upwards
Often premonitory signs are absent, a sudden death is first sign
Tachypnoea/dyspnoea
Pyrexia (41-42)

Question 18

Pathological findings of pneumonic pasteurellosis

Answer 18

Acute fibrinous pneumonia
- Congestion
- Consolidation
- (Hepatinization)
- Pleurisy
Usually an anterior distribution, may be confined to one diaphragmatic lobe
Congestion with oedema fluid and fibrin in alveoli in the centre of the lesion

Question 19

Systemic pasteurellosis

Answer 19

Can be caused by both Bibersteinia trehalosi and Manheimia haemolytica

Question 20

Bibersteinia trehalosi

Answer 20

Commensal of RT and tonsil
Causes septicaemia/endotoxaemia
Commonest in autumn and winter
Acute severe disease
Common strains: T3, T4, T10, T15
Mortality up to 20%
Sheep rarely seen alive, but signs of septicaemia may be noticed
Enlarged LNs, cardiac petechiation, serosal surface petechiation, lungs are oedematous and congested

Question 21

Manheimia haemolytica

Answer 21

Young lambs up to 2 months
Septicaemia that results in sudden death
Severe depression, congestion of mucus membranes with cold extremities
Petechiae on liver, spleen, kidneys and myocardium
Treat with Macrolides/tetracyclines/fenicols

Question 22

Chronic lung abscessation

Answer 22

Trueperella pyogenes, Actinobacillus lignieresii, and Staphylococcus aureus
Very common in sheep
Can be secondary to Pasteurella pneumonia
Often have an overlying area of pleurisy
Poor BCS, nasal discharge, increased resp rate
Treatment has little effect

Question 23

Caseous lymphadenitis

Answer 23

Abscesses surrounded by a very thick capsule and containing the bacteria (Corynebacterium pseudotuberculosis)
Clinical signs: increased resp rate and effort, areas of reduced ventilation
Rupture can be a cause of sudden death
Purulent material is thick and non-odorous, onion ring shape
Treatment is difficult due to impenetrable abscesses so cull

Question 24

Mycoplasma pneumonia/atypical pneumonia/enzootic pneumonia

Answer 24

Chronic, non-suppurative interstitial pneumonia
Predominantly young sheep
Likely Mycoplasma ovipneumoniae
Coughing, pyrexia, tachypnoea, dyspnoea on exercise
CrV part of lungs, dark red or greyish pink areas of consolidation - cuffing pneumonia
Treat with oxytet

Question 25

Ovine pulmonary adenomatosis (OPA)

Answer 25

Contagious, viral, chronic, progressive, neoplastic disease of the lung Dyspnoea, exercise intolerance, death Oncovirus of retroviridae family Proliferation of neoplastic cells on type 2 pneumocytes 1-20% of flock may die of it Long incubation period (1-3yrs) Wheelbarrow test Ventral lung becomes consolidated No specific treatment - slaughter

Question 26

Maedi-visna

Answer 26

Chronic, progressive, invariably fatal Visna viruses Chronic pneumonia, poor body condition, maybe mastitis and arthritis Lymphoid infiltration of lung and smooth hyperplasia (2-4x heavier), do not collapse when removed from the thorax Control by slaughtering sero-positive cases or make maedi free flock by rearing lambs separately Visna is a chronic demyelinating leukoencephalomyelitis

Question 27

CAE

Answer 27

Lentivirus of Retroviridae family Only a small % of those affected show clinical signs Adults usually polysynovitis-arthritis, chronic interstitial pneumonia, and indurative mastitis Kids usually encephalitis Lymphoproliferative lesions with degenerative mononuclear infiltration

Question 28

Ovine parasitic bronchitis and pneumonia

Answer 28

Dicyocaulus filaria Adults reside in the large bronchi Eggs hatch in intestines Primarily in lambs Coughing, tachypnoea, reduced appetite, weight loss, discharge from eyes and nose Patent phase: bronchitis and bronchiolitis with frothy mucus Late stages: non-suppurative eosinophilic granulomatous pneumonia usually in the caudal lung lobes Treat with levamisole

Question 29

Mullerius capillaris

Answer 29

Lungworm Lesions on dorsal aspect of lungs Raised greenish nodules Do not get bad enough to cause death - incidental findings