Respiratory diseases of pigs Flashcards
(85 cards)
1
Q
What is an upper respiratory disease of pigs caused by toxigenic pasturella multocida?
A
progressive atrophic rhintis
2
Q
What is an upper respiratory disease of pigs caused by toxigenic pasturella multocida?
A
progressive atrophic rhintis
3
Q
What causes non-progressive rhinitis in pigs?
A
- bordetella bronchiseptica
2. procine cytomegalovirus (inclusion body rhinitis)
4
Q
What causes progressive rhintis?
A
- toxogenic pasturella multcida +/- 2. other agents which enhance colonization (bordetella, cytomegalovirus),
- environmental (high ammonia, dust)
5
Q
What is the epidemiology of progressive rhinitis?
A
- agents causing rhinitis wide-spread
- toxigenic PM limited to herds with progressive atrophic rhinitis
- horizontal transmission (sow piglet, piglet-piglet)
6
Q
What age of pig gets INFECTED with progressive atophic rhinitis?
A
7
Q
What is the pathogenesis of progressive atrophic rhintis?
A
- pre-existing damage to mucosa assists colonization of TPM (infections, environmental)
- infection with TPM
- dermonecrotic toxin production
- permanent turbinate destruction
8
Q
What does toxogenic pasturella multocida produce and what does it do?
A
Dermonecrotic toxin causes 1. decreased osteogenesis 2. increased osteolysis ==>turbinate damage
9
Q
What are the clinical signs of progressive atrophic rhinitis in an ENDEMICALLY INFECTED FARM
A
sneezing (SUCKING AND NURSERY PIGS)
little or no epistaxis
little or no snout deviations
SUBCLINICAL TURBINATE ATROPHY
10
Q
What are the clinical signs of progressive atrophic rhinitis in an ENDEMICALLY INFECTED FARM
A
sneezing
little or no epistaxis
little or no snout deviations
SUBCLINICAL TURBINATE ATROPHY
11
Q
What causes non-progressive rhinitis in pigs?
A
- bordetella bronchiseptica
2. procine cytomegalovirus (inclusion body rhinitis)
12
Q
What causes progressive rhintis?
A
- toxogenic pasturella multcida +/- 2. other agents which enhance colonization (bordetella, cytomegalovirus),
- environmental (high ammonia, dust)
13
Q
What is the epidemiology of progressive rhinitis?
A
- agents causing rhinitis wide-spread
- toxigenic PM limited to herds with progressive atrophic rhinitis
- horizontal transmission (sow piglet, piglet-piglet)
14
Q
What space is used to check for turbinate atrophy in progressive atrophic rhinitis?
A
the space between the nasal septum and the vental scroll (plus check septal deviation, dorsal space)
15
Q
What is the pathogenesis of progressive atrophic rhintis?
A
- pre-existing damage to mucosa assists colonization of TPM (infections, environmental)
- infection with TPM
- dermonecrotic toxin production
- permanent turbinate destruction
16
Q
What does toxogenic pasturella multocida produce and what does it do?
A
Dermonecrotic toxin causes 1. decreased osteogenesis 2. increased osteolysis ==>turbinate damage
17
Q
What are the clinical signs of rhintis?
A
sneezing nasal discharge (no blood)
18
Q
What are the clinical signs of progressive atrophic rhinitis in an ENDEMICALLY INFECTED FARM
A
sneezing
little or no epistaxis
little or no snout deviations
SUBCLINICAL TURBINATE ATROPHY
19
Q
What are the clinical signs of progressive atrophic rhinitis in a NAIVE FARM (epizootic)
A
- severe sneezing (ANY AGE)
- NASAL HEMORRHAGE (any age)
- lacrimation
- facial deformities (chronic)
- growth retardation (grow finish)
20
Q
How does toxigenic pasturella multocida cause growth retardation
A
- metabolic impact of toxin
2. reduced feed intake due to facial deformities
21
Q
How is progressive atrophic rhinitis diagnosed?
A
- facial deformities, epistaxis (herd basis)
- sneezing (NOT pathopneumonic)
- tubinate atrophy @slaughter
- deep nasal swab–culture, ID toxin–ELISA, PCR
22
Q
Where is the snout sectioned to look at progressive atrophic rhinitis?
A
at the level of the first/second premolar
23
Q
What is the epidemiology of mycoplasma hyopneumoniae?
A
- two to three weeks
- horizontal transmission (sow-piglet, pig-pig)
- expression in GROWER PIGS >10WEEKS
- REGIONAL spread via aerosol-water droplets (although poor environmetnal survival)
24
Q
What are two snout score thresholds that indicate PAR requiring intervention
A
multiple individual scores >3.5
average score >1
25
What are the principles of progressive atrophic rhinitis control
1. decrease concurrent colonization (improve air quallity, separate age groups, feed medication)
2. antimicrobials targeted at TPM (prior and after weaning)--oxytet parenteral and feed Ab
3. vaccination of sow herd--pre-farrowing (passive immunity)
26
What must a vaccine for progressive atrophic rhinitis contain?
TPM, Bb, toxoids
27
Why should you do a pre-farrowing vaccination of breeding herd for PAR
to enhance passive and mucosal immunity
28
What causes enzootic penumonia?
mycoplasma hyopneumoniae
29
What is a contributor to procine respiratory disease complex
mycoplasma hyopneumoniae
30
What is severity of enzootic penumoniae influenced by?
1. MH strain
2. pig flow
3. animals per air space
4. pen density
5. air quality
31
Should you use culture to diagnose mycoplasma hyopneumoniae?
NO!
32
What is the epidemiology of mycoplasma hyopneumoniae?
1. two to three weeks
2. horizontal transmission (sow-piglet, pig-pig)
3. expression in GROWER PIGS >10WEEKS
4. regional spread via aerosol
33
Is the epizootic herd presentation of mycoplasma hypneumoniae common or uncommon?
uncommon
34
What are the issues with using serology to diagnose mycoplasma hyopneumoniae at the herd level?
No correlation between vaccine titre and protection
seroconversion HIGHLY VARIABLE and may require 6wks in natural infection
LOW SENSITIVITY--not for individual pig (but specificity high)
35
Does toxogenic pasteurella multocida spread regionally?
no
36
What is the endemic herd presentation of mycoplasma hyopneumoniae?
1. chronically infected herds
2. exposed in GROWER BARN
3. coughing in early grower period
4. high morbidity, low mortality
37
What is the treatment and control for mycoplasma hyopneumoniae?
1. vaccination of sow, nursery, grower
2. strategic medication
3. environmental control
4. control other resp pathogens and ascarids (PRDC)
38
What are the clinical signs of Mycoplasma hyopneumoniae?
1. non-productive, dry raspy cough (uncomplicated)
2. productive coughing if concurrent infections
3. tacypnea, dyspnea
4. uneven growth rates
39
What is severity of enzootic penumoniae influenced by?
1. MH strain
2. pig flow
3. animals per air space
4. pen density
5. air quality
40
What environmental control can be done to prevent m. hyo pneumoniae infection?
improve indoor air quality
| segregate age groups
41
How is mycoplasma hyopneumoniae diagnosed on an individual basis?
FAT-antigen
| PCR-DNA
42
How is mycoplasma hyopneumoniae diagnosed on a population basis?
1. Serology
2. slaughter check scoring
3. confirmatory testing (PCR, FAT on slaughter lungs)
43
What are the issues with using serology to diagnose mycoplasma hyopneumoniae at the herd level?
No correlation between vaccine titre and protection
seroconversion HIGHLY VARIABLE and may require 6wks in natural infection
LOW SENSITIVITY--not for individual pig (but specificity high)
44
What are lungs score intervention levels for mycoplasma hyopneumoniae
individual lesions scores >5%
| prevalence of infected lung >15-20%
45
Why might confirmatory testing of lungs at slaughter for myccoplasma hyopneumoniae be unreliable?
1. comingling of positive and negative pigs at assembly yard
| 2. scalding tank
46
What is the treatment and control for mycoplasma hyopneumoniae?
1. vaccination of sow, nursery, grower
2. strategic medication
3. environmental control
4. control other resp pathogens and ascarids (PRDC)
47
What are different vaccination strategies that can be used to control mycoplasma hyopneumoniae?
1. vaccinate sows, then delay piglet vaccination until maternal antibodies dropped
2. vaccinate progeny (suckling or nursery)
48
Does antimicrobial medication eliminate m. hyo infection?
NO. reduce infection pressure and control bacteiral infections
49
What environmental control can be done to prevent m. hyo pneumoniae infection?
improve indoor air quality
| segregate age groups
50
What are three diseases that cause coughing and dyspnea?
1. mycoplasma hyopneumonia (enzootic pneumonia)
2. swine influenza virus
3. actinobacillus pleuropneumoniae
51
What type of virus is the swine influenza virus?
type A influenza virus (orthomyxoviridae)
52
What are the two ways swine influenza can evolve?
drift--point mutations
| shift--reassortment
53
What was the original source of swine influenza virus?
humans
54
What type of swine influenza was seen from 1930-1998?
classic swine H1N1
55
What type of swine influenza emerged in 1998?
H3N2
56
How did the H3N2 virus originate?
from triple reassortment from human, swine and avian
57
What is the epidemiology of swine influenza?
1. highly infectious
2. most often late fall and winter
3. direct contact (nasopharyngeal secretions)
4. airborne spread in hog dense regions
58
What is the pathogenesis of swine influenza?
1. short incubation 1-3d
2. rapid replication
3. tropism for bronchiolar epithelium
4. cytokine secretion
5. epithelial cell necrosis
6. exudate accumulation
7. rapid virus clearance
59
What are the signs of classic H1N1?
1. explosive coughing (sudden onset)
2. paroxysms "seal bark"
3. high morbidity, low mortality
4. rapid recovery 5-7d
60
What are the clinical signs of modern swine fever?
1. variable and potentially subtle resp signs
2. all ages
3. herd presentation varies
61
What is the gross pathology of swine influenza?
1. conjunctivitis and nasal discharge
2. consolidation of cranial and middle lobes
3. enlarged and edematous bronchial/mediastinal LN
4. blood tinged fibrinous exudate
5. interlobular edema
6. gross lesions similar to mycoplasma hyopneumoniae
62
What is the distribution of swine influenza in lung pathology?
anteroventral
consolidation
checkerboard appaerance
63
What is the histopathology of swine influenza?
necrotizing bronchitis/bronchiolitis
airways/alveoli filled with exudate
bronchointerstitial pneumonia
64
How is swine influenza diagnosed?
1. histopathology (necrotizing bronchiolitis and bronchitis)
| 2. confirmation via PCR, IHC
65
Why might a false negative occur with swine influenza?
lesions come and go very quickly
| may get false negative >8 days post infection
66
What kind of antibody is used with SIV IHC?
type A antibody
| works in all species
67
How is diagnosis of SIV done on a population level?
1. serology--serotypes specific or generic
2. PCR--nasal swabs
3. genomic analysis
68
When is the best time to collect a sample for SIV?
48 hr post exposure (24hr of showing signs)
69
What are 4 aspects of treatment and control of SIV?
1. anti-inflammatories
2. antimicrobials (2ndry infection)
3. improve indoor air quality
4. vaccination--commercial vs autogenous
70
What are the most virulent serotypes of actinobacillus pleuropneumoniae?
1
5
7
71
What is the epidemiology of actinobacillus pleuropneumoniae?
1. primarily horizontal transmission
2. not likely to transmit between herds
3. short incubation periods (6-12hrs)
72
Which resp disease is likely to transmit between herds in hog dense areas: SIV or actinobacillus pleuropneumoniae?
SIV
73
Severity of actinobacillus pleuropneumoniae depends on what?
1. serotype
2. exposure dose
3. immune status of herd
4. concurrent dz
74
Which resp disease has an incubation period of 6-12hrs?
actinobacillus pleuropneumoniae
75
What is the pathogenesis of actinobacillus pleuropneumoniae?
1. colonize tonsils, alveolar epithelium
2. phagocytosed by macrophages
3. produce 4RTX exotoxins
4. inflammatory cytokine production
5. septic shock
6. arteriolar thrombosis and alveolar necrosis
76
What exotoxins does actinobacillus pleurpneumoniae produce?
4 RTX exotoxins (Apo I, II, III, IV)
77
What do the exotoxins and the cytokines involved in actinobacillus pleuropneumoniae infection cause?
1. septic shock (peracute death)
| 2. arteriolar thrombosis and alveolar necrosis
78
What are the clinical signs of actinobacillus pleuropneumoniae?
1. peracute: cyanosis, foamy bloody nasal discharge, found dead
2. acute: dyspnea, coughing, agonal breathing
3. chronic: chronic pleuritis-->chronic cough; reduced appetite/growth
79
What is the pathology of peracute and acute actinobacillus pleuropneumoniae?
necrotizing and hemorrhagic pneumoniae
well demarcated, usually CAUDAL LOBES
focal pleuritis
80
What is the pathology of chronic actinobacillus pleuropneumoniae
1. chronic pleuritis and adhesions
2. consolidation and necrosis
3. pulmonary abscesses
81
Why is pleuritis an important feature to look for when looking for actinobacillus pleuropneumoniae
because carcasses going through a scalding tank can look like they have hemorrhagic pneumoniae but they wont have pleuritis
82
How is actinobacillus pleuropneumoniae diagnosed at the individual level?
1. necrotizing hemorrhagic pneumoniae with focal pleuritis
| 2. culture and serology
83
What types of serology is there for actinobacillus pleuropneumoniae?
1. generic ELISA
2. specific for individual serotype
(remember some cross react)
84
How is actinobacillus pleuropneumoniae controlled?
1. environmental control
2. strategic medication
3. vaccination (serotype specific, autogenous)
85
Does actinobacillus pleuropneumoniae vaccine protect against infection? are they used much in canada?
no and no
