Lecture 14: Trueperella, Rhodococcus, Listeria and Erysipelothrix Flashcards
What is the shape of trueperella spp and is it gram positive or negative
Pleomorphic (coccobacillary, rod, club shaped), gram positive bacilli, non-spore forming
Trueperella spp are __anaerobes and aerobes
Facultative
T or F: Trueperella are capnophilic
True
Where are Trueperella spp found
Mucous membranes of mammals- commensals
What is the primary Trueperella spp. of veterinary importance
T. Pyogenes
What is the shape of T. Pyogenes
Coccobacillary to short rods
T. Pyogenes is a normal inhabitant of where
Upper respiratory, urogenital and GI tracts of ruminants, swine and other mammals
T. Pyogenes is a ___pathogen, most infections are endogenous
Opportunistic
What causes T. Pyogenes
Traumatic inoculation, secondary infection
T. Pyogenes can have host-to-host transmission in what scenario
Mastitis in cows
What does T. Pyogenes cause in tissues
Suppurative lesions, abscesses, emyemas, pyogrnaulomas
How does T. Pyogenes spread in body
Hematogenous
What are the virulence factors associated with T. Pyogenes and what do they do
- Pyolysin O: cytotoxic to macrophages, neutrophils and RBC’s
- Neuroamindases and other adhesins bind host cells and ECM
What is T. Pyogenes synergistic with
Fusobacterium necrophorum which causes bovine liver abscesses
What does T. Pyogenes cause in swine
Septic arthritis, occurs after farrowing
What does T. Pyogenes cause in cattle
Severe mastitis in heifers and dry cows, profuse, purulent secretions (contagious)
How is T. Pyogenes transmitted in cattle
Flies, teat contact with contaminated environment or milking equipment
How do you dx T. Pyogenes
- Clinical findings and gram positive short Pleomorphic rods
- Culture and ID- PCR of A.pyogenes, and MALDI-TOF
What is tx for T. Pyogenes
- Drainage of abscess
- Antibiotics- in vivo response poor because abscess encapsulation
How can you control T.pyogenes mastitis
Control flies, disinfection, tx heifers and dry cows with prophylactic long acting penicillin, isolate/ cull
What is the shape of Rhodococcus spp and are they gram positive or negative
Pleomorphic (cocci, rods, filaments), gram positive
Rhodococcus spp are __ so found in soil and water
Saprophytes
What is the important rhodococcus spp in vet med
R. Equi
What are the shapes of R. Equi
Cocci, coccobacilli, rods
What are the reservoirs for R. Equi
Soil and intestinal tracts and feces of healthy animals
R. Equi are __ pathogens primarily of __
Opportunistic, foals
What are the routes of infection for R. Equi
Inhalation or ingestion of virulent strains in soil
What does R. Equi cause to tissues
Granulomas, pyogranulomas, abscesses
How does R. Equi spread in body
Hematogenous
Pathogenic strains of R. Equi are __pathogens so they survive and grow inside ___
Facultative intracellular pathogens, grow inside macrophages
What protects R. Equi from phagocytic killing
Vap proteins
Foal presents with abscesses and histo shows pyogranulomas and the following image. What is likely cause
R. Equi (macrophages filled with R. Equi)
What does R. Equi cause in foals
Pyogranulomatous bronchopneumonia with abscessation. Lesions in pulmonary, mesenteric LN, intestines
What does R. Equi do to swine
Causes submandibular and cervical lymphadentitis
foal necropsy shows abscesses all over lungs, what is likely cause
R. Equi
How can you dx R. Equi
- Gram positive Pleomorphic cells within macrophages from tracheal wash, pus
- PCR for VapA gene
What is tx for R. Equi
Rifampin and macro life
What shape are listeria spp and are they gram negative or positive
Gram positive, coccobacilli
Listeria spp are __anaerobes
Facultative
Listeria are ___, so commonly found in soil and water
Saprophytes
What does L. Ivanovii cause in ruminants (especially sheep_
Abortion
What does L. Monocytogenes cause in mammals
Septicemia, abortion and CNS infections
Where is L. Monocytogenes found
Soil, silage, sewage, freshwater, GI tracts and feces
How is L. Monocytogenes transmitted
- Ingestion of contaminated food
- Vertical transmission in utero
What is the pathogens is of L. Monocytogenes
- Penetrates intestinal epithelium
- Spreads via lymph and blood to various tissues
- Alternative route ton CNS via breaks in oral or nasal mucosa—> cranial nerves—> brain
What lesions are associated with L. Monocytogenes
- Brain- microabscesses, primarily in brain stem
- Septicemia- diffuse necrosis in any organ, especially liver
- Aborted fetus
L. Monocytogenes is a ___pathogen so grows inside ___ and ___
Facultative intracellular pathogen, phagocytic and non-phagocytic cells
What are the virulence factors associated with L. Monocytogenes
- Adhesins
- Listeriolysin O
what does this show and what is likely cause
Infected neuron within a micro abscess
Likely cause: L. Monocytogenes
What does L. Monocytogenes cause in cattle
- Encephalitis (most common)
- Abortion in 3rd trimester
- Septicemia in neonates
What does L. Monocytogenes cause in pigs, dogs and cats
Septicemic form with focal hepatic necrosis
What does L. Monocytogenes cause in horses
Neonatal septicemia and abortion
What does L. Monocytogenes cause in poultry
Septicemic form with lesions in heart, liver, and other abdominal viscera, pericarditis, splenomegaly
necropsy of chicken shows necrotic lesion on heart. What is likely cause
Septicemic form of L. Monocytogenes
How can you dx L. Monocytogenes
- Gram positive rods in liver, other organs, placental or fetal tissue
- Culture and ID
How can you tx L. Monocytogenes
Antibiotics- penicillin, oxytetracycline
How can you control/ prevent L. Monocytogenes
- Avoid feeding poor quality silage
- Implement feeding methods that minimize ocular contact with silage
What is the shape of erysipelothrix spp and are they gram positive or negative
Gram positive, non-spore forming rods or non-branching filaments
Erysipelothrix are __anaerobes
Facultative
What is the most important erysipelothrix species in vetmed
E. Rhusiopathiae
What is the important reservoir for E. Rhusiopathie
Pigs
Where does E. Rhusiopathie live in pigs
Tonsils and GI tract- excreted in feces and pro nasal secretions
Healthy carrier pigs
How do infections with E. Rhusiopathie occur
Ingestion of contaminated food or water, also via skin wounds
What is the pathogens is of E. Rhusiopathie
- Invades bloodstream
- Vascular damage and hemorrhagic lesions in organs/tissues
- Damage to synovial joints
What virulence factors are associated with E. Rhusiopathie
- Neuroamindases- adherence to endothelial cells
- Hyaluronidase- invasion of tissue
- Capsule- survival and growth in phagocytic cells (facultative intracellular pathogen)
Pig necropsy shows synovitis and arthritis in hock joint. Black=hemorrhage, what bacteria is the likely cause
E. Rhusiopathie
How does E. Rhusiopathie effect swine
- Severe septicemia- skin lesions, high mortality, pregnant sows abort
- Mild septicemia- skin lesions and pregnant sows abort
- Chronic form- arthritis and endocarditis
What age group of pigs is most susceptible to E. Rhusiopathie
3-18 months
What does E. Rhusiopathie cause in lambs and how does infection occur
Polyarthritis, infection via umbilicus and skin wounds
What does E. Rhusiopathie cause in adult sheep
Post dipping lameness, pneumonia, endocarditis
15 month old Pig presents with the following lesions, just aborted fetus. What is likely cause
E. Rhusiopathie
What can E. Rhusiopathie cause in poultry, especially turkeys
Acute septicemia with sudden death
Dark colored, swollen snood
Chronic arthritis or endocarditis may occur
What caused this dark colored, swollen snood
E. Rhusiopathie
Which bacteria can be an occupational hazard to vets working with fish, poultry, swine and in agricultural industries
E. Rhusiopathie
How do you dx E. Rhusiopathie
- Gram positive short to filamentous rods
- Culture, PCR, MALDI-TOF
What is the treatment for E. Rhusiopathie
- Penicillin- DOC
- Tetracycline
What tx should be added to suckling piglets with E. Rhusiopathie
Antiserum with antibiotics
