Respiratory conditions Flashcards
Signs of upper respiratory infection
Stridor
Sneezing
Nasal discharge
Increased resp rate
Coughing
Referred abnormal lung sounds
Signs of lower respiratory infection
Extension of neck
Elbow abduction
Nasal discharge
Increased resp rate
Coughing
Abnormal lung sounds (CV)
Exercise intolerance
Dyspnoea
Causes of URT disease (6)
- Nasal myiasis
- Laryngeal chondritis
- Nasal foreign bodies
- Nasal tumours:
Adenopapillomas or polyps
Squamous cell carcinomas - adenomas
Adenocarcinomas
Nasal myiasis
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)
Pharyngeal trauma
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
Laryngeal chondritis
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
Ilex choke
Sudden death or acute choke
Reported in lambs that have holly or ilex leaves obstructing pharynx
Common causes of viral pneumonia
Parainfluenza virus type 3
Ovine adenovirus
Common causes of viral respiratory disease
Maedi-visna
Ovine pulmonary adenocarcinoma (Jaagsiekte)
Common causes of bacterial pneumonia
Manheimia haemolytica
Bibersteinia trehalosi
Pasteurella multocida
Mycoplasma ovipneumoniae
Most common cause of parasitic pneumonia
Dicyocaulus filaria
Clinical signs of acute viral pneumonia
Mild respiratory signs
Not always pyrexic
Cough
Serous nasal discharge
Conjunctival discharge
Usually not lethal
Can lead to secondary bacterial infections
Diagnosis of acute viral pneumonia
Often unnoticed until more chronic
PM
BAL/transtracheal washes
PCR
Treatment of acute viral pneumonia
Antibiosis to prevent bacterial overgrowth
NSAIDs
Pasteurellosis
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
Clinical disease of pasteurellosis
Four different presentations
- Septicaemia and sudden death (birth to weaning)
- Pneumonia (older lambs)
- Mastitis
- Joint ill in lambs
Clinical signs of pneumonic pasteurellosis
Acute pneumonia from about 2 months upwards
Often premonitory signs are absent, a sudden death is first sign
Tachypnoea/dyspnoea
Pyrexia (41-42)
Pathological findings of pneumonic pasteurellosis
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
Systemic pasteurellosis
Can be caused by both Bibersteinia trehalosi and Manheimia haemolytica
Bibersteinia trehalosi
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
Manheimia haemolytica
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
Chronic lung abscessation
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
Caseous lymphadenitis
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
Mycoplasma pneumonia/atypical pneumonia/enzootic pneumonia
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
Ovine pulmonary adenomatosis (OPA)
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
Maedi-visna
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
CAE
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
Ovine parasitic bronchitis and pneumonia
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
Mullerius capillaris
Lungworm
Lesions on dorsal aspect of lungs
Raised greenish nodules
Do not get bad enough to cause death - incidental findings
