Respiritary Disease

Question 1

Clinical evidence of a respiratory problem

Answer 1

• coughing
• thumping or dyspnoea
• fever
• nasal discharge

Question 2

Things to think about with housing and environment

Answer 2

• ventilation
• stocking rate
• all-in - all-out?
• mixing of age groups in a single airspace?
• temperature control
• humidity

Question 3

Diseases in the suckling period (4)

Answer 3

• Glasser’s
• PRRS
• Enzootic pneumonia
• Swine influenza

Question 4

Diseases in the weaners, growers and finishers (8)

Answer 4

• bordetella (3-4 weeks)
• *Glasser’s (3weeks- adult)
• *enzootic pneumonia (6-8 weeks - finisher)
• *PRRS (4-12 weeks -adult)
• mucoplasma hyorhinis (3-4weeks - adult)
• *pleuropneumonia (6-8 weeks +)
• *pasteurellosis (6 weeks +, mainly 12 weeks +)
• *influenza

Question 5

Diseases in Adults (6)

Answer 5

• influenza
• PRRS
• Glassers
• Enzootic pneumonia
• pleuropneumonia
• pasteurellosis

Question 6

Progressive atropic rhinitis

Facts (6)

Answer 6

• neonatal, non-immune piglets
• toxigenic P multiocida Type D
• colonises in nasal cavity after initial damage by bordetella
• osteoblasts killed by toxin or transform into fibroblasts
• osteoclastic activity is stimulated
• no remodelling of conchae and facial bones

Question 7

CS of Progressive atropic rhinitis (5)

Answer 7

• severe sneezing, blockage of lachrymal ducts
• epistaxis, purulent rhinitis
• distortion of the snout
• shortening of the upper jaw and malocclusion of the teeth
• depression of the growth rate by 30-40g/day

Question 8

PM Progressive atropic rhinitis

Answer 8

• shortening of the upper jaw
• absence of conchae at premolar 2
• distortion of nasal septum
• isolation of toxigenic P. multocida

Question 9

Progressive atropic rhinitis

• Epidemiology (5)
• Dx (4)
• Tx
• control (4)

Answer 9

• spread via respiratory route
• spread in carrier pigs
• spread by formites
• rapid killing by drying
• survives in water for 14 days

Dx;

• CS & PM
• isolation of toxigenic P multocida
• PCR
• serum antibody to toxin

Tx:
- penicillin/ampicillin/tylosin/trimethoprim sulphonamide (parenternally)

control:

• interrupted treatment of above at 2, 10 and 21 days
• vaccination
• colostrum
• al in, all out

Question 10

Glasser’s disease

Answer 10

• haemophilus parasuis
• infection by the upper respiratory tract –> bacteraemia –> septicaemia/localises to cayse polyserositis, meingitis or arthritis in 12-36 hours
• serotypes 4&5 are most pathogenic

Question 11

Glasser’s disease CS (8)

Answer 11

• 3-6 weeks or more (recently weaned are most common)
• fever
• anorexia and reduced water intake
• nasal discharge, tachypnoea and coughing
• lameness
• fluctuant, hot, swollen joints
• meningitis
• death within 2-5 days

Question 12

Glasser’s disease pathology (7)

Answer 12

• purulent rhinitis
• fibrinous pleurisy, peritonitis and pericarditis
• enlarged spleen
• petechial haemorrhage
• turbid joint fluid
• purulent meningitis
• bronchopneumonia

Question 13

Glasser’s disease

epidemiology (3)
Dx (3)

Answer 13

• direct transmission
• rapidly killed by drying
• maternal antibody protects for 2-4 weeks

Dx:

• CS : fever, lameness, swollen ears
• PM: fibrinous peritonitis, pleurisy and pericarditis
• H. Parasuis isolation from trachea

Question 14

Glasser’s disease

• Tx (3)
• Control (3)

Answer 14

Tx:

• parenternal medication of individuals
• water medication of groups (but remember they have a reduced water intake!)
• penicillin/ amoxycillin/ampicillin/tetracycline/ceftiofur/enrofloxacillin/treimethoprim sulphonamide

control:

• feed medication of above at risk period
• vaccination
• minimise stress

Question 15

Enzootic pneumonia (6)

Answer 15

• mycoplasma hyopneumoniae
• inactivated by drying within 48hours
• respiratory entry
• adhere to cilia of tracheal, bronchial and bronchiolar epithelium
• cause clumping and loss of cilia
• 2 week incubation

Question 16

Enzootic pneumonia CS (5)

Answer 16

• 3-10 weeks old
• barking cough
• lasts ± 50 days
• uneven size: depression of growth rate and feed conversion

Question 17

Enzootic pneumonia pathology

Answer 17

• classic pneumonia of cranial middle and cranial portion of caudal lobe and accessory lobe
• enlarged bronchial LNs
• fawn colour of early lesions
• ## well demarcared

Question 18

Enzootic pneumonia

epidemiology (3)
Dx (6)

Answer 18

epidemiology:

• carrier pigs
• aerosol for 3km
• formites for short distances

Dx:

• coughing pigs with uneven growth
• dry, non-productive cough
• characteristic lung lesions
• cuffing type pneumonia
• demonstration by PCT, IP or IF
• ELISA

Question 19

Enzootic pneumonia

Answer 19

Tx:

• water medication with tiamulin/tetracucline/doxycycline/tylosin/florfenicol
• feed medication
• perenternal treatment of severely affected with tiamulin, tetracyclines, florfenicol

Control:

• low heard level use of tetracyclines/tiamulin/tylosin (continuous, pulsed or strategic)
• vaccination
• isolation
• depopulation and restocking
• all in all out
• avoid mixing and moving

Question 20

PRRS

• CS (2)
• pathogenesis

Answer 20

CS:

• laboured breathing in piglets only with acute breakdown
• raised respiratory rate in weaners and growers accompanied by flushing of the skin

Pathogenesis:

• infection by respiratory rate, contact or at insemmination
• viraemia –> destruction of alveolar macrophages –> multlipication in endothelial cells leading to plasma leaks –> interstitial pneumonitits

Question 21

PRRS

pathology (7)

Answer 21

Pathology:

• anterior lobe rubbery pneumonia
• excess pleural and pericardial fluid
• enlarged LN
• blebbing of bronchiolar epithelium
• no alveolar macrophages
• proliferative interstitial pneumonia
• type 2 pneumocyte proliferation

Question 22

PRRS

• Dx (6)
• Control (5)

Answer 22

DX:

• CS
• PM
• absence of alveolar macrophages and interstitial pneumonia
• virus isolation
• serology (ELISA) 3 weeks later
• PCR

Control:

• isolation
• purchase sero-negative pigs
• use of filtration on air intakes
• three sites production
• vaccinate

Question 23

Influenza (7)

Answer 23

• aerosol or contact infection
• incubation of 1-2 days
• virus multiplies in epithelial cells of tracheobronchial tree infecting most cells by 24 hours
• infected neutrophil-rich exudate in bronchioles
• recovery by day 9
• more common in winter
• bird and man may introduce

Question 24

Influenza CS (9)

Answer 24

• whole herd involvement
• lethargic
• prostration
• anorexia
• fever
• productive cough, sneezing and dyspnoea
• conjunctival discharge
• loss of condition
• abortion/return to service in sows

Question 25

Influenza pathology (6)

Answer 25

- sharply demacated plum coloured lung lesions - mucus and exudate in bronchi - old lesions are depressed, pale and firm - thickened alveolar septae - bronchi filled with shed neutrophils etc. - proliferative lesion of bronchiolar epithelium

Question 26

Influenza - Dx (4) - Control (4)

Answer 26

Dx: - CS and PM - demonstration of virus in lesions - rise in serum antibody to virus strain only - virus isolation control: - vaccination is restriced to sows only - treat assymptomatically - isolate herd

Question 27

Pleuropneumonia Facts (5)

Answer 27

- pleurisy and pneumonia - actinobacillus pleuropneumoniae - gram negative coccobacillus - 3 main toxins: 1,2,3 --> each may be haemolytic or cytotoxic or both - sensitive to drying

Question 28

Pleuropneumonia pathogenesis (2)

Answer 28

infection by contact/aerosol --> bacreria adhere to tonsillar epithelium --> inhaled alveoli in non-immune pigs where they multiply (mainly in diaphragmatic lobes) --> adhere to alveolar epithelium - resist phagocytosis by capsules and complement resistence

Question 29

Pleuropneumonia CS (7)

Answer 29

- rapid onset (3-6 hours) from 6-8 weeks - fever - coughing can be severe enough to cause vomiting - raised RR and respiratory distress with froth on the lips - exercise intolerance, inappetence & dehydration - congested extremities - death can occur 4-6 hours after CS onset

Question 30

Pleuropneumonia pathology (5)

Answer 30

- carcase dehydrated. poor condition, froth on lips, cold extremities - excess pleural and pericardial fluid - pneumonia in diaphragmatic lobes - lesions red or black before pleurisy but rapidly become covered in fibrin - lesions become firm and whitish with necrotic centres

Question 31

Pleuropneumonia ``` economic impacts (4) transmission (5) ```

Answer 31

- reduced growth rate - reduced feed converstion - death - lesions at slaughter Transmission - aerosol/contact - continuous stocking - mixing pigs - carrier pigs - high humidity, low temps

Question 32

Pleuropneumonia - Dx (6) - Tx (4) - Control (3)

Answer 32

DX: - CS - lesions - isolation - demonstration of antigens in tissue - PCR - demonstration of serum antibody to cytotoxin Tx: - penicillin/tetracyclines/ampicillin/florfenicol/ceftiofur/tiamulin - parenternal treatment for sick pigs - feed medication for later stages and pervention - Tx does not cure lesions control: - isolation and purchase of free pigs - all in all out system - vaccinate

Question 33

Pneumonic pasteruellosis (9)

Answer 33

- pasteurella multocida type A - secondary to enzootic pneumonia or other diseases - causes acute pneumonia with fever and congestion of extremeities - fibrinous pleurisy common - die or become chronically infected - treat acute disease parenteranlly - water medicate group - penicillin/tetracycline/cetiofut/trimethoprimm sulphonimide/florfenicol - improve ventilation and reduce ammonia levels