pigs Flashcards
1
Q
A
2
Q
What are the five zoonotic porcine pathogens?
A
- Brachyspira pilosicoli - Clostridioides difficile - Erysipelothrix rhusiopathiae - Salmonella species - Streptococcus suis
3
Q
What are eight general predisposing stressors to infection?
A
- Drafts 2. Inappropriate temperature for age and temperature fluctuations 3. Inadequate ventilation parameters 4. Excessive humidity (NH3 and CO2) 5. Overcrowding and fighting 6. Diet inadequacies 7. Mixing of pig sources, ages, or sizes 8. Secondary to major pathogens (PPRSV, SIV, PCV2, etc.)
4
Q
Which bacteria causes “diamond skin disease”?
A
Erysipelothrix rhusiopathiae (zoonotic)
5
Q
What are the three “suisidal” bacteria in pigs?
A
- Streptococcus suis (zoonotic) 2. Glaesserella parasuis 3. Actinobacillus suis
6
Q
What are the six common clinical manifestations or pathological lesions of the “suisides”?
A
- Septicemia (all three) - Arthritis (all three) - Meningitis (all three) - Pericarditis (all three) - Polyserositis (effusion of several serous membranes in body at the same time, ex. the pleura, pericardium, peritoneum) - all three - Vegetative valvular endocarditis (only Streptococcus suis)
7
Q
Which presentation does Streptococcus equi zooepidemicus most commonly cause in pigs?
A
Septicemia
8
Q
Which presentation does Mycoplasma hyorhinis most commonly cause in pigs?
A
Polyserositis and arthritis
9
Q
Which bacterial agents commonly cause systemic disease in nursery piglets? What post-mortem signs would you see?
A
- Glaesserella parasuis - Streptococcus suis - Mycoplasma hyorhinis Necropsy Findings: Polyserositis and/or arthritis
10
Q
Which bacterial agents commonly cause systemic disease in grower-finisher pigs?
A
- Actinobacillus suis - Mycoplasma hyopneumoniae - Erysipelothrix rhusiopathiae Tend to be more pneumonic agents
11
Q
What is the most common necropsy finding in a pig that died from systemic disease?
A
Polyserositis and/or arthritis
12
Q
What are three characteristics of Erysipelothrix rhusiopathiae?
A
- Gram-positive rod - Worldwide - Pigs are an important reservoir
13
Q
Where does Erysipelothrix rhusiopathiae replicate in pigs?
A
In the tonsils and intestinal tract
14
Q
What are two virulence factors of Erysipelothrix rhusiopathiae?
A
- Neuraminidase (provides nutrients, aids in adhesion and tissue invasion) 2. Capsular polysaccharides (resistance to phagocytosis by leukocytes and intracellular killing by macrophages)
15
Q
How is Erysipelothrix rhusiopathiae transmitted?
A
- Direct contact with infected animals - Indirect contact with environmental fomites shed in excretions (urine, feces) and secretions (saliva, nasal mucus)
16
Q
What is the pathogenesis of Erysipelothrix rhusiopathiae?
A
- Oral exposure with initial infection of the tonsils or gastrointestinal mucosa (bacteria may also enter through skin abrasion or mechanical vectors) 2. Bacteria survive and replicate in macrophages 3. Bacteremia develops within 24 hours 4. Septicemia results in distribution of bacteria throughout the body 5. Bacteremia causes widespread vasculitis, fibrinous thrombosis, diapedesis, and necrosis
17
Q
What are the three clinical forms of Erysipelothrix rhusiopathiae?
A
Acute, subacute, and chronic
18
Q
What are the clinical signs of acute diamond skin disease?
A
Clinical signs: Septicemia, abortions, depression, lethargy, pyrexia, stiff gait (painful joints), inappetence, sudden death Characterized by pink/red/purple raised firm rhomboid/squared “diamond skin” lesions
19
Q
What are the clinical signs of sub-acute diamond skin disease?
A
Less severe than acute. Clinical signs: Temperature may or may not be high, animals may eat less Skin lesions may be few or absent
20
Q
What are the clinical signs of chronic diamond skin disease?
A
Follows acute, subacute or subclinical infections. Clinical signs: Chronic arthritis (3 weeks after initial outbreak), reduction in feed intake, respiratory distress , lethargy, cyanosis or sudden death Main lesion seen is vegetative valvular endocarditis
21
Q
What are “erysipelas”?
A
Classic diamond shaped lesions found in diamond skin disease (sometimes it looks like they also called the disease itself “erysipelas”)
22
Q
Which samples should you collect for testing for diamond skin disease?
A
- Joint tissue - Skin biopsy - Liver - Spleen - Kidney - Heart valves
23
Q
What laboratory tests should you use to diagnose diamond skin disease in pigs?
A
- Culture and susceptibility 2. Serotyping 3. Immunohistochemistry (IHC) 4. in situ Hybridization (ISH) 5. PCR testing
24
Q
What are three differential diagnosis for erysipelas?
A
- Acute septicemia and/or sudden death in grower-finishers (ex. Salmonella, Actinobacillus suis, Actinobacillus pleuropneumoniae, Glaesserella parasuis, Streptococcus suis) 2. Skin lesions caused by classical swine fever virus or porcine dermatitis and nephropathy syndrome (PDNS) 3. Vegetative valvular endocarditis caused by Streptococcus suis
25
Is Streptococcus suis Gram-positive or Gram-negative?
It is a Gram-positive cocci
26
What are two virulence factors of Streptococcus suis?
1. Capsular polysaccharides (anti-phagocytic) 2. Hemolysin suilysin (toxic to epithelial, endothelial and phagocytic cells)
27
How is Streptococcus suis transmitted?
- Direct contact and aerosolization - Vertical transmission (post-weaned piglets = most susceptible)
28
What is the pathogenesis of Streptococcus suis?
1. Colonization of the tonsils/upper respiratory tract 2. Invasion of respiratory mucosa (uptake or adherence to monocytes) 3. Capsule resists phagocytosis and causes a bacteremia 4. Release of inflammatory cytokines leads to septic shock 5. Invades endothelial cells and multiples in subarachnoid space 6. Induced inflammation increases permeability of BBB causing cerebral edema 7. Increased intracranial pressure causes impaired circulation 8. Finally, we see CNS clinical signs
29
What are the three forms of Streptococcus suis?
1. Per-acute (found dead due to septic shock) 2. Acute (septicemia, meningitis, polyserositis, polyarthritis) 3. Chronic (arthritis, vegetative valvular endocarditis)
30
What are the clinical signs of Streptococcus suis (non-specific, septicemic, and neurologic)?
Non-specific: Fever, inappetence, depression, weakness Septicemic: Sudden death, dyspnea, cyanosis, swollen joints, lameness Neurologic: Listlessness, incoordination, dog-sitting, paddling, opisthotonos, convulsions, nystagmus
31
What lesions do we see with Streptococcus suis?
Lymphadenopathy, meningitis, arthritis, vegetative valvular endocarditis, polyserositis, splenomegaly, petechial hemorrhages
32
What samples should you collect to test for Streptococcus suis in pigs?
- Fibrinous exudate - Brain - Synovium and joints - Heart valves - Lung - Liver - Spleen - Kidney
33
What laboratory tests should you use to diagnose Streptococcus suis in pigs?
1. Culture and susceptibility 2. Serotyping
34
What are some differential diagnosis for Streptococcus suis in pigs?
- Polyserositis (G. parasuis, M. hyorhinis) - Meningitis (G. parasuis) - Endocarditis (E. rhusiopathiae) - Septicemia (G. parasuis, A. suis. E. coli, E. rhusiopathiae, Salmonella) - Polyarthritis (M. hyorhinis, M. synoviae, E. coli, A. suis)
35
Which bacteria causes Glässer's disease?
Glaesserella parasuis
36
Is Glaesserella parasuis Gram-positive or Gram-negative?
It is a Gram-negative rod
37
How is Glaesserella parasuis transmitted?
Direct contact with carrier or diseased pigs
38
What are two virulence factors of Glaesserella parasuis?
1. Lipopolysaccharide (LPS) (induces disseminated intravascular coagulation producing microthrombi) 2. Capsular polysaccharide (helps to prevent macrophage phagocytosis)
39
What is the pathogenesis of Glaesserella parasuis?
1. Nasal cavity and trachea are the primary sites of colonization 2. Stress induced or secondary to viral infection 3. Epithelial invasion, replication, and dissemination (septicemia)
40
What are the clinical signs of Glässer's disease in pigs?
1. 4 to 8-week-old piglets: incubation period of 2. Peracute: short course ( 3. Acute: high fever (41.5°C), coughing, abdominal breathing, swollen joints with lameness, CNS signs (lateral recumbency, paddling, trembling) 4. Chronic: rough hair, reduced growth rate, lameness
41
What are the three types of lesions seen with Glässer's disease in pigs?
1. Peracute (no characteristic gross lesions, may show petechial hemorrhages in some organs 2. Acute (fibrinous to fibrinopurulent polyserositis (pleura, pericardium, peritoneum, synovia, meninges), polyarthritis and meningitis, serosanguinous fluid in the thoracic and abdominal cavities) 3. Chronic (severe fibrosis of the pericardium, pleura, and/or peritoneum, chronic arthritis)
42
What samples should you collect if you want to test for Glässer's disease in pigs?
- Lung - Heart - Liver - Spleen - Kidney - Brain - Synovium and joints
43
What laboratory tests should you use to diagnose Glässer's disease in pigs?
1. Culture and susceptibility 2. Serotyping 3. PCR testing 4. IHC / ISH
44
True or False: Clinical signs and lesions are not pathognomonic for Glässer's disease in pigs
True. Other bacterial agents should be on your list!
45
Glaesserella parasuis is said to be fastidious. What does this mean?
It means it is difficult to grow and it also dies quickly because it's easily overgrown by other bacteria!
46
What are some characteristics of Actinobacillus suis?
- Gram-negative rod - Opportunistic pathogen (normally colonizes tonsils and respiratory tract)
47
What are three virulence factors of Actinobacillus suis?
1. Capsular Polysaccharides (anti-phagocytic) 2. OmpA (adhesion to brain microvascular endothelial cells) 3. RTX toxins (haemolytic and cytotoxic, impairs phagocytic function of macrophages)
48
How is Actinobacillus suis transmitted?
Direct contact or aerosolization
49
When is the prevalence of Actinobacillus suis the highest?
It is greater in new herds before animals develop immunity
50
What are the clinical signs of Actinobacillus suis?
Sudden death, lameness, fever, neurological signs
51
What are the three forms of Actinobacillus suis and which specific clinical signs are seen in each?
1. Acute fulminant septicemia in suckling and recently weaned pigs (found dead) 2. Respiratory disease in grower and finisher pigs (cough, fever, anorexia) 3. Septicemia in adult pigs (lethargy, anorexia, fever, and rhomboid skin lesions resembling Erysipelas)
52
What lesions are seen in each of the three forms of Actinobacillus suis?
1. Acute fulminant septicemia - Petechial to ecchymotic hemorrhages in multiple organs - Serous to serofibrinous exudates in the thoracic and abdominal cavities - Pleuritis, pericarditis, arthritis 2. Respiratory disease - Multifocal or diffuse hemorrhagic and necrotizing pneumonia or pleuropneumonia - Petechial hemorrhages on serosa organs, +/- fibrinous peritoneal exudate 3. Septicemia - Multifocal petechial hemorrhages, serofibrinous exudate, +/- small foci of hepatic necrosis - Rhomboid skin lesions
53
What samples should you collect to test for Actinobacillus suis in pigs?
- Lung - Heart - Spleen - Liver - Kidney - Brain - Synovium and joints
54
What laboratory tests should you use to diagnose Actinobacillus suis in pigs?
Culture and susceptibility testing
55
What are the key differences between all the "suisides"?
Honestly these are all basically exactly the same so you have to rely on the culture results, not the gross lesions. The only difference appears to be that Streptococcus suis causes endocarditis and the other two don't. The other clue you might have is that Actinobacillus suis affects grower-finisher pigs and Glaesserella parasuis and Streptococcus suis affect nursery piglets more
56
What three virulence factors does Streptococcus equi zooepidemicus have?
1. Capsular polysaccharides (anti-phagocytic) 2. Hyaluronidase (promotes tissue dissemination) 3. Streptolysin S (beta-hemolysis)
57
How is Streptococcus equi zooepidemicus transmitted?
Direct contact and aerosolization
58
What lesions are seen with Streptococcus equi zooepidemicus?
- Splenomegaly - Fibrinous peritonitis - Petechial hemorrhages - Hemorrhagic lymphadenopathy
59
What samples should you collect to test for Streptococcus equi zooepidemicus?
- Liver - Kidney - Heart - Lung - Spleen - Brain
60
What laboratory tests should you use to diagnose Streptococcus equi zooepidemicus in pigs?
Culture and susceptibility testing
61
True or False: Streptococcus equi zooepidemicus lesions are pathognomonic
False, they are not not pathognomonic so other pathogens must be on your list too!
62
What is unique about Mycoplasma hyorhinis?
It lacks a cell wall and is enclosed in a plasma membrane
63
What age of pig does Mycoplasma hyorhinis mostly affect?
Young nursery pigs
64
What virulence factors does Mycoplasma hyorhinis have?
Lipoproteins (stimulates cytokine production by macrophages)
65
How is Mycoplasma hyorhinis transmitted?
Direct contact with nasal secretions
66
What is the pathogenesis of Mycoplasma hyorhinis?
1. Bacterium binds to ciliated respiratory epithelium of the nasal cavity and conducting airways 2. Lipoproteins embed themselves into the cell membrane 3. Systemic invasion occurs from sites of mucosal colonization (mechanism of invasion is unknown)
67
What are the clinical signs in nursery pigs with Mycoplasma hyorhinis (non-specific, respiratory, arthritis)?
Non-specific: Fever, lethargy, anorexia Respiratory: Dyspnea Arthritis: Swelling of one or more joints, lameness
68
What lesions do you see in nursery pigs with Mycoplasma hyorhinis?
- Fibrinous serositis (pleura, pericardium, and/orperitoneum) - Synovial membranes are edematous with fibrinosuppurative exudate
69
What samples should you collect to test for Mycoplasma hyorhinis?
1. Fibrin or swabs of serosal surfaces 2. Fibrin, swabs or fluid of joints 3. Fluid from pleura, pericardial, peritoneal cavities
70
What laboratory tests should you use to diagnose Mycoplasma hyorhinis in piglets?
PCR testing (remember, this dude doesn't have a cell wall so you can't Gram-stain him)
71
What are some differential diagnosis for Mycoplasma hyorhinis in piglets?
- Polyserositis/polyarthritis caused by G. parasuis, S. suis, A. suis - Arthritis cause by Mycoplasma synoviae
72
Which pathogens cause systemic lesions in pigs?
Erysipelothrix rhusiopathiae, all three "suisides”, Streptococcus zooepidemicus, and Mycoplasma hyorhinis
73
What are the general characteristics of Actinobaculum suis?
- Gram-positive rod - Anaerobic - Normal flora of boar prepuce **Do not get this confused with Actinobacillus suis**
74
Actinobaculum suis is classified as a ________________ pathogen
Urogenital (remember, most of the others are systemic!)
75
What are the three clinical manifestations of Actinobaculum suis most commonly seen in sows or gilts?
Cystitis, pyelonephritis, and metritis
76
What are the virulence factors of Actinobaculum suis?
Adhesion and production of urease
77
How is Actinobaculum suis transmitted?
Direct transmission via mating with an infected boar (females develop infection 1-3 weeks later)
78
What is the pathogenesis of Actinobaculum suis?
1. Increase in urine pH (estrus) enhances bacterial growth and migration 2. Inadequate water supply leads to crystalluria 3. Urease production 4. Damage to bladder defences 5. Infection by ascending route (bladder, ureters, kidneys) 6. Requires alkaline conditions for growth
79
What are the three phases of the clinical signs of Actinobaculum suis?
1. Acute: Hematuria 2. Later: Weight loss, uremic, bloodstained, purulent urine +/- vaginal discharge 3. Mild: Inappetence and vaginal discharge
80
What lesions do you see with infection by Actinobaculum suis?
Urinary mucosa: inflamed fibrinopurulent exudate Kidneys/ureters: dilated renal pelvis containing mucopurulent fluid, dilated ureters filled with reddish purulent urine
81
What samples should you collect to test for Actinobaculum suis?
- Urine - Bladder - Kidneys - Purulent fluid - Vaginal discharge - Semen
82
What laboratory tests should you use to diagnose Actinobaculum suis?
Bacterial culture - Anaerobic!
83
What are the two primary porcine respiratory pathogens?
- Actinobacillus pleuropneumoniae (pleuropneumonia) - Mycoplasma hyopneumoniae (pneumonia)
84
What are the five secondary porcine respiratory pathogens?
- Pasteurella multocida (atrophic rhinitis, pneumonia) - Bordetella bronchiseptica (atrophic rhinitis, pneumonia) - Actinobacillus suis (pneumonia) - Glaesserella parasuis (fibrinous pleuritis, pneumonia) - Streptococcus suis (pneumonia)
85
What are the main zoonotic porcine pathogens? (5)
Brachyspira pilosicoli, Clostridioides difficile, erysipelothrix rhusiopathiae, salmonella spp, and streptococcus suis.
86
What are the 7 general predisposing stressors of infections?
1. Drafts 2. Inappropriate temp 3. Poor ventilation 4. Excessive humidity 5. Overcrowding/fighting 6. Diet inadequacies 7. Mixing of pig groups
87
What is the causative agent of diamond skin disease?
Erysipelothrix Rhusiopathiae, a gram positive rod
88
Transmission of Erysipelas
Direct contact with infected animals, or indirect contact through fomites
89
What are the virulence factors of Erysipelas
Neuraminidase: aids in tissue invasion Capsular polysaccharides: resistance to phagocytosis
90
Acute Erysipelas
Presents as septicemic disease: sudden death, depression, lethargy, fever, characteristic pink/red/purple raised diamonds on skin
91
Subacute Erysipelas
Less severe, not as sick, temp not as high, lower mortality, may have few or absent skin lesions
92
Chronic Erysipelas
Follows acute, subacute or subclinical infection. Leads to chronic arthritis with enlargement of leg joints, resp distress, or sudden death due to vegetative valvular endocarditis
93
How do we diagnose Erysipelas?
Take liver, spleen, heart tissue, or joint tissue and send for culture & susceptibility
94
Streptococcus suis
Gram pos cocci, Has 35 serotypes, but only 1 & 2 associated with septicemia and other bad things.
95
What are the virulence factors of Strep. Suis?
Capsular polysaccharides (antiphagocytic) Hemolysin - toxic to cells
96
Transmission of Strep suis
Direct contact, aerosolization, vertical transmission
97
Clinical signs of peracute Strep suis
Found dead due to septic shock
98
Clinical signs of acute strep suis
Septicemia, meningitis, polyarthritis
99
Clinical signs of chronic strep suis
Arthritis, vegetative valvular endocarditis
100
Diagnosis of strep suis
Sample of heart, lung, or liver for culture & susceptibility
101
Glasser's disease
Glasserella parasuis; gram-negative rod
102
What are the virulence factors of Glasser's disease?
LPS endotoxin, and capsular polysaccharide
103
Transmission of Glasser's disease
Direct contact with carriers or diseased pigs
104
Clinical signs of peracute Glasser's disease
Short course <48 hours then sudden death without lesions
105
Clinical signs of Acute Glasser's disease
High fever, swollen joints, CNS signs. May find fibrinous polyserositis, polyarthritis, and meningitis on PM
106
Clinical signs of chronic Glasser's disease
Rough hair, reduced growth rate, lameness. May find severe fibrosis of the pleural tissues and chronic arthritis on PM
107
Glasser's disease Diagnosis
Lung, heart, liver tissues for culture & susceptibility
108
Actinobacillus Suis
Gram-negative rod, opportunistic pathogen
109
What are the virulence mechanisms of Actinobacillus suis?
Capsular polysaccharide, OmpA (adhesion to brain microvascular endothelial cells)
110
Actinobacillus suis transmission
Direct contact or aerosolization
111
What are the three forms of actinobacillus suis?
1. Acute fulminant septicemia 2. Respiratory disease 3. Septicemia
112
What does acute fulminant septicemia in actinobacillus suis look like?
Hemorrhages in organs, serous exudates in thoracic cavity, pleuritis, pericarditis, and arthritis.
113
What does the respiratory form of actinobacillus suis look like?
Hemorrhagic and necrotizing pneumonia
114
What does the septicemic form of actinobacillus suis look like?
Hemorrhages, serofibrinous exudate, and rhomboid skin lesions
115
Actinobacillus suis diagnosis
Lung, liver, heart samples to be sent for culture and susceptibility. Treat with abx
116
What are the similarities between the suis? (strep suis., G parasuis., A suis.,)
They are found in the nasopharynx, lesions are multisystemic, and they result in pneumonia, pericarditis, meningitis, arthritis, and peritonitis.
117
What are the differences between the suis? (strep suis., G parasuis., A suis.,)
A. suis doesn't have strain variation Strep suis is the only one that causes endocarditis
118
Strep. equi zooepidemicus
gram pos cocci in chains found on skin/mucous membranes of sows
119
Strep. equi zooepidemicus virulence factors
capsular polysaccharide, hyaluronidase (promotes tissue dissemination), and streptolysin S (causes beta hemolysis)
120
Strep. equi zooepidemicus clinical signs
fever, lethargy, abortions, sudden death
121
Strep. equi zooepidemicus lesions
splenomegaly, fibrinous peritonitis
122
Strep. equi zooepidemicus diagnostics
liver, kidney, heart samples for culture and susceptibility
123
Mycoplasma Hyorhinis
Lacks a cell wall, commensal of the nasohparynx
124
Mycoplasma Hyorhinis virulence factor
Lipoproteins - stimulate inflammatory reaction by macrophages
125
Mycoplasma hyorhinis clinical signs
pigs 3 to 10 weeks of age. non-specific fever, lethargy, and anorexia, a respiratory dyspnea, and arthritis. Will have a fibrinous serositis on PM
126
Mycoplasma Hyorhinis diagnosis **
Fibrin or swabs of the serosal surfaces, joints, for PCR
127
Actinobaculum suis causes what 3 diseases mainly?
Cystitis, Pyelonephritis, metritis
128
Actinobaculum suis
Gram positive, anaerobic rod, normal flora of boar prepuce
129
Actinobaculum suis virulence factors
Adhesion and production of urease
130
Actinobaculum suis - what are the three phases?
1. Acute: hematuria 2. Later: bloodstained, purulent urine 3. Mild: inappetence & vaginal discharge
131
Actinobaculum suis What are the lesions on PM?
The urinary mucosa is inflamed with fibropurulent exudate, and the kidneys have dilated renal pelvis with mucopurulent fluid
132
Actinobaculum suis diagnosis
Sample the urine, bladder, kidney, or vaginal discharge for an anaerobic bacterial culture
133
True or False: Clinical signs and lesions are not pathognomonic for Glässer's disease in pigs?
True. Other bacterial agents should be on your list!
