Module 3 (Spiral And Curved Bacteria) Flashcards
• These organisms are major
causes of gastrointestinal
infections in human, dogs and
cats with diarrhea.
• These are short, curved rods.
• They are found in the
reproductive and alimentary
tracts of humans and animals.
Compylobacter
Species of Campylobacter associated with animal infections
• Campylobacter fetus subsp.
venerealis (Cattle)
• C. jejuni
• C. coli
• C. consicus
• C. helveticus
• C. hyointestinalis
• C. mucosalis
• C. lari
Species of Lawsonia associated with animal infections
L. intracellularis
• Gram-negative, slender
curved short rods.
• Two or more bacterial cells that
are placed together form S or a gull-
winged shapes.
• These organisms possess cell wall,
capsule and flagella.
Campylobacter and Lawsonia
• These organisms are microaerophilic and require
an atmosphere containing 3 to 15% oxygen.
• Their growth does not require fermentation or
oxidation of carbohydrates as their energy
requirement is reportedly obtained from oxidation
of amino acids.
Compylobacter
It has not reportedly been
grown in artificial media.
Lawsonia intercellularis
Reservoir of infection from Compylobacter
• Milk
• Poultry carcass and intestinal tracts
of infected animals
• Feces of infected pigs
(L. intracellularis) and preputial crypts of the bull (C. fetus sp. venerealis)
Transmission of Compylobacter
•Feco-oral route
•Artificial insemination and coitus
•Direct or indirect contact
Diseases associated with Campylobacter
- Campylobacter infection in Dogs and Cats
- Campylobacter infections in Cattle
- Campylobacter infections in Sheep and birds
- Campylobacter infections in Swine
• Etiologic agent: C. jejuni
• Infection is marked by diarrhea and gastroenteritis
• Pathogen invades the distal segments of the small intestines
• The mucosal epithelium is destroyed, destroy arachidonic acid pathway, produces prostaglandins and leukotrienes and elevation
of cAMP
• Diarrheic feces contain cell debris and mucus that irritates epithelium and renders feces
bloody
• L. intracellularis causes necrotic enteritis, regional ileitis and proliferative hemorrhagis enteropathy
Campylobacter infection in Dogs and Cats
• Etiologic agent: C. fetus subsp. venerealis
• The disease is marked by infertility and abortions and cattle are healthy shedders of
Campylobacter infections
Campylobacter infections in Cattle
• Etiologic agent: C. fetus subsp. fetus
• The disease is marked by abortion in sheep
and birds
Campylobacter infections in Sheep and birds
• Etiologic agents: C. hyointestinalis and C. mucosalis
• The disease is marked by proliferative enteritis
Campylobacter infections in Swine
Virulence factors of Campylobacter
(cellular product of Lawsonia spp. in
presently unknown)
• Toxin similar to cholera toxin
• Heat-labile toxin (LT, increases
intracellular levels of CAMP)
• Toxin with cytotonic and
cytotoxic activity
• Cyto-lethal distending toxin
• Hemolysin
• Hepatotoxin
• Mannose resistant adhesin
• Survival in mononuclear
phagocytes
Laboratory diagnosis of Compylobacter
SAMPLES: Feces and intestinal scrapings,
preputial samples and smegma and
stomach contents
PREFERRED CULTURE MEDIA: Blood and Thiol agar
Agent Identification for Compylobacter
• Microscopic examination of wet mounts
(Tumbling motility)
• Staining of bacterial smears in Romanovsky
stain (curved rods) and Warthin-Starry
(modified acid-fast stain)
• Bacterial cultivation and isolation (Campy-CVA
medium)
• Amplification of campylobacter DNA through
PCR
Treatment with antibiotics
for Compylobacter
• Tetracyclines
• Erythromycin
• Tylosin
• Quinolones
Control and prevention for Compylobacter
• Adherence to hygienic measures and
disinfection protocols
• Gram negative aerobes
• Microbes are rarely involved
with a primary disease
• Difficult to eliminate when they
contaminate a compromised site
• Produce grapelike and/or
ammoniacal odors
• Replace the normal flora after
antibiotic therapy (resistance
to some antibiotics
PSEUDOMONAS
Species associated with animal
infections for Pseudomonas
➢P. mallei
➢P. pseudomallei
➢P. aeruginosa
➢P. maltophilia
➢ Gram-negative aerobes
➢ Capsules may be produced
➢ Motile (polar flagella)
➢ Piliated in some forms
➢ Form many protein exotoxins (A, S), elastase, bacteriocins (Pyocins),
pigments (pyocyanins), siderophores, pyochelins and pyoverdin
Pseudomonas
Growth characteristics of Pseudomonas
➢ Growth is hastened by blood
agar
➢ Grow on all common media
that contain glycerol and
blood over a wide range of
temperature (4-41C)
➢ ferments glucose
Reservoir of infection Pseudomonas
• Soil
• Infected water
• Infected hosts
Transmission of Pseudomonas
➢ Environment
➢ Endogenous exposure
➢ Contaminated feeds, water
and fomites
➢ Ingestion of the pathogen
➢ Bacterial entry through
wound infections
Diseases associated with Pseudomonas
- Glanders in horses
- Melioidosis in Humans (mimic disease
- Green Wool Infection (Sheep)
4.Ear infections (Dogs and cats)
Etiologic agent: P. mallei
(Burkholderia mallei)
➢ Systemic pyo-granulomatous
infection of horses
➢ Entry through the pharynx
➢ Penetration of the nasopharyngeal (nasal form)
➢ Invades the regional lymphatics and spreads to various sites
➢ Bacteria produce nodular lesions on the way to lymph nodes and blood stream
➢ Marked by thick nodules and ulcers in the mucus membranes of upper respiratory tract
➢ Metastatic lesion form in the lungs and skin
Glanders in Horses
Clinical signs of glanders
➢ Nasal discharges
➢ Lymphadenitis of the head and neck
➢ Swellings along the upper respiratory tract (Pulmonary form)
➢ Pain in muscle
➢ Dermal abscesses (Cutaneous/Farcy)
➢ Nodular induration of cranial lymph nodes
3 forms of glanders
• Pulmonary
• Nasal
• Skin (farcy)
➢ (Pseudomonas pseudomallei or
Burkholderia pseudomallei)
➢ Suppurative foci or granulomas
systemically
Melioidosis in humans
(mimic disease)
Other Pathogenic Entities
(Pseudomonas aeruginosa)
➢Green Wool Infection (Sheep)
➢Ear infections (Dogs and cats)
Virulence factors of Pseudomonas
➢ Exotoxin A (inhibits protein synthesis)
➢ Extracellular slime (antiphagocytic action and facilitates penetration of pathogen in the tissue)
➢ Elastase (destroys the lung parenchyma, pneumonia cases)
➢ Bacteriocins and pigments
➢ Pyocyanin and siderophores
Laboratory diagnosis of Pseudomonas
Samples: Nodules from the nasal
passages, lymph nodes,
blood
Agent Identification
➢ Bacterial cultivation (glycerol-enriched or other selective media)
➢ Mallein Test (Subcutaneous, ophthalmic and intra-palpebral)
➢ Bacteriocin typing (pyocin kills other strains of the same species of bacteria)
➢ Phage typing (spotting of known phages on the overlay of test strains suggestive of lysis patterns, kills other Pseudomonas except P. aeruginosa)
Treatment for Pseudomonas
➢ Gentamycin
➢ Carbenicillin
➢ Tobramycin
➢ Ciprofloxacin
➢ Ticarcillin
➢ Cluvanilic acid
➢ Enrofloxacin
➢ Neomycin
Prevention and control for Pseudomonas
➢ Early diagnosis and elimination of
reacting animals
➢ Culling/ elimination of infected animals
➢Coccobacillary forms of bacteria
➢Invaders of ciliated respiratory epithelia
BORDETELLA
Species of associated with animal
infections
➢B. bronchiseptica
➢B. avium
➢B. pertussis
➢B. parapertussis
➢ Gram-negative coccobacilli
➢ Small, blue-gray colonies on the surface of blood agar
➢ Piliated and show bipolar staining
➢ Pleomorphic with capsulated envelope (B. bronchiseptica)
➢ Motile by means of peritrichous flagella
➢ Some forms possess surface covering of fibrils
➢ Heat-labile and heat-stable K antigens
BORDETELLA
Growth characteristics of Bordetella
➢ Aerobic
➢ Utilize citrate as source of carbon
➢ Derive energy from oxidation of
amino acids
➢ Facultative intracellular parasite
(living within phago-lysosomes of
phagocytic cells (B. bronchiseptica)
Reservoir of Infection of Bordetella
➢ Wild and domestic carnivores
➢ Nasopharynx of healthy animals
➢ Carrier sows
Transmission of Bordetella
➢ Airborne
➢ Water
Disease associated with Bordetella
- Swine atrophic rhinitis
- Kennel cough
- Rhinotracheitis in turkeys
- Acute coryza in turkeys
- Pneumonia in sheep
Etiologic agent : B. bronchiseptica
• Ciliated respiratory epithelium
• Cilial paralysis and inflammation
• Nasal irritation
• Turbinates irritated by dermonecrotic toxin
• Depressed respiratory clearance
and secondary bacterial infections
Swine atrophic rhinitis
Clinical Signs of Swine atrophic rhinitis
➢ Sneezing and coughing
➢ Atrophy of the turbinate bones
➢ Distortion of nasal septum
➢ Shortening and twisting of upper jaw
(Canine infectious tracheobronchitis
of dogs)
Etiologic agent : B. bronchiseptica
• Marked by hacking cough
Kennel cough
Etiologic agent : B. avium
• Marked by sinusitis and air sacculitis
• Nasal exudates, conjunctivitis, rales and dyspnea
Rhinotracheitis in turkeys
• Obstruction of ciliated respiratory epithelium
Acute coryza in turkeys
Etiologic agent: B. parapertussis
Pneumonia in sheep
Virulence Factors of Bordetella
➢ Siderophores
➢ Histamine-like scrutinizing factor
➢ Adhesins
➢ Oxidase
➢ Urease
➢ Catalase
➢ Adenylate cyclase
➢ Fibrillar material
➢ Dermonecrotic toxin
➢ Proteases
➢ Hemolysins
➢ Hemagglutinins
➢ Tracheal cytotoxins
Laboratory diagnosis of Bordetella
Samples: Tracheal aspirates, nasal swabs,tissues [taken after transverse section of the head at the level of pre-molar teeth]
Agent identification
➢ Bacterial cultivation (Bordet-Gengou agar, Blood agar, Brain Heart infusion broth)
➢ Serodiagnosis
Treatment for Bordetella
➢ Erythromycin
➢ Nitrofurantoin
➢ Tetracycline
Prevention and control for Bordetella
➢Disinfection and sanitation
➢Fumigation of kennels
➢Elimination of carrier animals
➢Isolation of infected dogs
➢ Obligate pathogens implicated
in infections of the reproductive organs and reticulo-endothelial tissues
➢ Infections lead to abortion in
females and epididymitis and
orchitis in males
➢ Infections are chronic and
debilitating
Brucella
Species associated with animal
disease Brucella
• B. abortus
• B. canis
• B. ovis
• B. melitensis
• B. suis
➢ Gram-negative short rods or coccobacilli
➢ Most colonies vary from smooth to rough with bluish color
➢ No capsules, flagella and spores
➢ Organisms are difficult to suspend in solution
➢ Positive to Koster staining,
Machiavello and modified Ziel- Nielsen stains
➢ The outer membrane possess
surface antigens (A and M)
Brucella
Growth characteristics of Brucella
➢ Aerobic at 37°C, 10 to 14 days
incubation (maximum 21 days)
➢ H2S producer
➢ Urease positive
➢ Requires an enriched medium
containing 5% serum or blood
➢ Vary in oxygen requirement
➢ Produce hydrogen sulfide, urease
and natural or mutagen-derived
bacteriophages
Reservoir of infection Brucella
• Cattle
• Swine
• Sheep
• Dogs
• Placenta and aborted fetuses
• Post-abortion uterine fluid
Transmission of Brucella
• Direct and indirect contact
(infected placentas and aborted fetuses
and post-abortion uterine fluids)
• Ingestion of an infected material
• Direct transfer in utero
• Venereal transmission
• Consumption of milk
Diseases associated with Brucella
A. Infectious abortions (any period
of gestation)
B. Poll evil (Equine brucellosis)
C. Infection in weanlings and suckling piglets (B. suis)
D. Infection in sheep, goats, pigs, cattle (B. ovis)
E. Infection in dogs (B. canis)
Etiologic agent: B. abortus
• Penetration of mucosal surfaces
• Attachment to specific organs
• Regional lymph nodes
• Proliferation in other cells [RES and
reproductive tract]
• Survival and multiplication inside
macrophages
• Inhibit phagolysosomal fusion
• Retained placenta in females
• Testicular infection in bulls
• Allantoic fluid factor (Erythritol)
stimulates growth of Brucella (gravid
uterus)
• Edematous fetus
A. Infectious abortions (any period
of gestation)
Fistulous withers
Poll evil (Equine brucellosis)
• Metritis, arthritis, spondylitis, lameness and paralysis and mastitis
Infection in weanlings and
suckling piglets (B. suis)
• Late abortion (50th day), lymphadenitis
• Splenitis, embryonic death, epididymitis
• Scrotal swelling, dermatitis and
testicular atrophy
Infection in dogs (B. canis)
Virulence factors of Brucella
• Superoxide dismutase
• A and M antigens
• Porin proteins and surface antigens
(outer membrane)
• L-form variants (persistence of
infection)
Samples:
Aborted fetus, placenta, uterine exudates, abscesses of the testes,
milk and blood, sputum, liver, spleen, mesenteric lymph node, abomasal fluid of aborted fetuses
Agent identification
➢ Bacterial culture and cultivation
(Albini/Brucella agar)
➢ Gram staining of fetal contents
➢ PCR and ELISA
➢ Brucella milk ring test
Laboratory diagnosis for Brucella
Treatment for Brucella
➢ Tetracycline
➢ Dihydrostreptomycin
➢ Minocyclin
Prevention and Control for Brucella
➢Culling of infected animals
➢Vaccination with B. abortus strain
19 or with McEwen killed 45/20 vaccine
➢Neutering affected animals