Bacteriology Flashcards
Mastitis- contagious pathogens
Staphylococcus aureus, Streptococcus agalactiae, Corynebacterium bovis, Trueperella pyogenes, Mycoplasma
Mastitis- environmental pathogens
Streptococcus dysgalactiae, Streptococcus uberis, Enterococcus, Escherichia coli, Klebsiella, Enterobacter, Pseudomonas
Coliform mastitis
E. coli, Klebsiella, Enterobacter
Most common cause of fatal mastitis
Mammary infarcts, thin, serosanguinous milk with fibrinous secretions
Staphylococcal mastitis
Second most common cause of fatal mastitis
Gangrenous teats (red/black), suppurative or granulomatous inflammation (firm, tan-white nodules), thick, tan milk
Listeriosis
Listeria monocytogenes
Bacteria found in poor-quality silage (high pH) and in dead/dying vegetation
Ingested bacteria travel up trigeminal nerve and form microabscesses in the brainstem
Characterized by unilateral cranial nerve signs, including vestibular signs
Tetanus
Clostridium tetani
Bovine footrot
Fusobacterium necrophorum
Ovine footrot
Dichelobacter nodosus
Bovine digital dermatitis (“hairy heel warts”)
Treponema
Bovine actinomycosis
“Lumpy jaw”
Actinomyces bovis
Woody tongue
Actinobacillus lignieresii
Bovine salmonellosis
S. typhimurium, S. newport, S. dublin
Most infections are subclinical, organisms are ubiquitous
Usually only causes disease if GI stasis or dysbiosis occur
Septicemia, acute or chronic enteritis, asymptomatic carrier state
Acute enteritis- fever, anorexia, foul-smelling diarrhea with casts/sheets of fibrin (sloughing mucosa), can be associated with dry gangrene of distal limbs
Ceftiofur is treatment of choice
Paratuberculosis (Johne’s disease)
Mycobacterium avium ssp. paratuberculosis
Persists in environment
Bovine enterotoxigenic Eschericia coli
Disease affects calves <3 days of age
Watery, yellow diarrhea, may have blood
Bovine clostridial enteritis
Clostridium perfringens type A- acute hemorrhagic abomasitis of calves (2-4 months of age)
C. perfringens type C- neurologic signs, sudden death
Fowl cholera
Pasteurella multocida
Severe pneumonia and/or septicemia
Chickens and turkeys >10 weeks of age
Carried by mammals and spread in the water
Sudden death, mucoid discharge from the mouth, ruffled feathers, diarrhea, and increased respiratory rate
Poultry salmonellosis
Many species of Salmonella, including Salmonella enteritidis which causes disease in humans
High mortality in birds <2 weeks of age
Omphalitis, peritonitis, cecal cores, hepatitis, myocarditis
Can cause paratyphoid in older birds - hepatomegaly, perihepatitis, airsacculitis
Porcine colibacillosis
Enterotoxigenic E. coli
Profuse yellow, watery diarrhea that can start as little as 12 hours as birth
Chyle in lacteals of small intestine mesentery
100% morbidity, high mortality
Vaccination and environmental control
Porcine edema disease
E. coli (may or may not be enterotoxigenic)
Shiga-like toxin damages vascular endothelium causing visible edema of stomach, colon, and eyelids
Neurologic signs result from edema and necrosis of the brain
Porcine salmonellosis
Salmonella typhimurium (enterocolitis) and S. choleraesuis (systemic disease)
Enteritis- yellowish diarrhea with or without blood, mesenteric lymphadenopathy, thickened intestines with fibrin, “button” ulcers in small intestine, rectal stricture*
Systemic- pneumonia, paratyphoid nodules; non-responsive to penicillin!
Swine dysentery
Brachyspira hyodysenteriae
Severe mucohemorrhagic diarrhea with high morbidity/moderate mortality
Large intestine only
Microscopic visualization of organism (spirochete)
Brachyspira pilisicoli (similar disease with less severe symptoms)
Porcine proliferative enteropathy
“Ileitis”
Lawsonia intracellularis
Dark, hemorrhagic diarrhea (acute) or intermittent diarrhea and wasting (chronic)
Hemorrhage and thickening of small intestine (“garden hose gut”)
PCR (culture NOT possible, intracellular organism)
Porcine mycoplasma pneumonia
Mycoplasma hyopneumoniae
Secondary infections are main concern (PRDC)
Chronic cough, especially induced by excitement/exercise
Other signs of illness mild or absent
Cranioventral lung consolidation
PCR (culture is difficult)
Vaccination recommended if exposure is likely
Porcine pleuropneumonia
Actinobacillus pleuropneumonia
Fever, labored breathing, hemorrhagic nasal discharge or saliva, sudden death
Minimal to no coughing
Pulmonary hemorrhage and infarction
Culture (requires NAD)
Porcine pasteurellosis
Pasteurella multocida
Chronic cough, decreased growth rate
Purulent bronchopneumonia
Culture
Porcine polyserositis (3 main causes)
Streptococcus suis - post-weaning; meningitis* (neurologic signs), pneumonia, polyserositis, neutrophilic
Haemophilus parasuis (Glasser’s disease) - post-weaning; meningitis, pneumonia, polyserositis*, neutrophilic
Mycoplasma hyorhinis- polyserositis, polyarthritis, lymphocytic
Culture
Porcine bordetellosis
Bordetella bronchiseptica
Hemorrhagic lobular consolidation in nursing/recently-weaned pigs
Can cause atrophic rhinitis n conjunction with Pasteurella multocida (sneezing, tearing, epistaxis, loss of nasal turbinates, distortion of snouts)
Porcine leptospirosis
Leptospira pomona* and L. bratislava
Most common sign is late-term abortion (3rd trimester)
Vaccination commonly recommened
Tetracycline antibiotics
Zoonotic
Porcine neonatal septicemia
Most commonly Streptococcus sp. and E. coli
“Navel ill”
Polyarthritis
Exudative dermatitis
Staphylococcus hyicus
Non-pruitic skin condition
Brown-to-black greasy exudate on skin
Eperythrozoonosis
Mycoplasma suis
Damages red blood cells
Fever, icterus, anemia
Erysipelas
Erysipelopthrix rhusiopathiae
“Diamond skin disease” - diamond skin lesions pathognomonic but uncommon
Arthritis/lameness, vegetative endocarditis, cutaneous erythema, sudden death
Penicillin
Vaccination recommended
Porcine cystitis/polynephritis
Actinobacterium suis
Fever, hematuria, PU/PD
Alkaline urine
Anthrax
Bacillus anthracis
Swine relatively resistant
Tuberculosis
Swine- Mycobacterium avium (of little concern)
Bovine- Mycobacterium bovis- firm, encapsulated nodules containing caseous material in lungs
Endocarditis
Bovine- Trueperella pyogenes, tricuspid valve (right-sided heart failure)
Ruminant sinusitis
Dehorning-associated - Trueperella pyogenes, frontal sinus, penicillin
Infected teeth - Pastueruella multocida, maxillary sinus, tetracyclines/macrolides
Nasal discharge, stridor, head tilt, exophthalmos, neurologic signs
Establish drainage!
Necrotic laryngitis
Calf diphtheria- infection of laryngeal mucosa and cartilage
Fusobacterium necrophorum
Inspiratory dyspnea, open-mouthed breathing, extended neck, halitosis, frequent swallowing
Arytenoid chondritis can result (fibrotic) - requires surgery
Mannheimia haemolytica (BRDC)
Necrotizing fibrinous broncho/pleuropneumonia (thoracic pain)
Leukotoxin - lysis of WBCs and platelets
LPS - endotoxemia
Cranioventral lung consolidation
Pasteurella multocida (BRDC)
Pneumonia
Less severe disease and shorter duration that M. haemolytica
Endotoxemia can occur
Cranioventral lung consolidation
Histophilus somni (BRDC + other)
Respiratory disease - pneumonia and fibrinous pleuritis
Neurologic disease - thromboembolic meningoencephalitis
Other disease - otitis polyarthritis, myocarditis (left ventricle)
Vasculitis and vascular thrombi + hypersensitivity-like reaction (produces histamine + IgE production)
Profound depression, tachypnea, stiffness, weakness/ataxia, lameness, sudden death
Vaccination available, chance of hypersensitivity reaction
Mycoplasma bovis (BRDC + other)
Contagious bovine pleuropneumonia, arthritis, tenosynovitis, otitis
Common complaint is animal is not responding to treatment (Mycoplasma)
Can be transmitted in milk to calves
Vaccination, must contain leukotoxin and be species-appropriate
Mycoplasma mycoides subsp. mycoides
Serious cause of mortality for kids and does
Peracute - high fever and rapid death
Neurologic syndrome - CNS signs and rapid death
Acute/subacute - high fever, swollen joints, pneumonia
Fibrinopurulent polyarthritis, ~50% have pneumonia
Culture milk
Trueperella pyogenes
Internal or subcutaneous abscesses in ruminants
Metastatic pneumonia - abscesses in lungs caused by septic thromboembolism often from liver abscesses secondary to ruminitis (other common organism is Fusobacterium necrophorum); epistaxis/hemoptysis, dyspnea, pallor (intrapulmonary hemorrhage), cor pulmonale (right-sided CHF)
Also associated with sinusitis following dehorning, contagious mastitis, and endocarditis
Caseous lymphadenitis
Corynebacterium pseudotuberculosis (also causes “pigeon fever” in horses and bovine ulcerative lymphangitis)
Disease of small ruminants
Internal form - pyogranulomatous abscesses mediastinal/mesenteric lymph nodes, lungs, and other internal organs
External form (most common) - abscessation of external lymph nodes
Culture of abscess contents
No antibiotics (uncurable), strict isolation while lesion is draining
Dermatophilosis
“Rain rot”
Dermatophilus congolensis
Infective zoospores activated by moisture
Non-pruritic lesions on dorsum and lower limbs
“Paint brush” tufts of fur overlying crusts - beneath crusts is pus and pink granulation tissue
Impression smear- 2-8 parallel rows (“railroad track” or “congo line”) of cocci bacteria
Infectious bovine keratoconjunctivitis
“Pinkeye”
Most common eye disease of cattle
Transmitted by flies
Moraxella bovis - cytotoxin that damages corneal epithelium resulting in a corneal ulcer
Synergism with bovine herpesvirus-1 and Mycoplasma infections (conjunctivitis)
Blepharospasm, epiphora, photophobia, corneal edema, ulcer
Topical antibiotics
Small ruminant keratoconjunctivitis
Mycoplasma conjunctivae
Epiphora, conjunctival hyperemia, usually unilateral
Recover spontaneously in ~10 days
Direct transmission, can be reinfected or become carrier
Chlamydophila pecorum
Epiphora, chemosis, conjunctival hyperemia
Bilaterally symmetric
Associated with polyarthritis
Usually self-limiting
Bovine anaplasmosis
Anaplasma marginale
Transmitted by Dermacenter tick species
Most cattle do not develop disease, become life-long carriers
Disease characterized by extravascular hemolysis - anemia, icterus, hemoglobinuria, weakness, high fever
Organisms on periphery of RBC on blood smear
Tetracyclines
Bacillary hemoglobinuria
Disease of cattle caused by Clostridium novyi type D
Bacteria gain entry into liver and remain quiescent - liver damage (often Fasciola hepatica) provides anaerobic environment for bacteria - toxins released into bloodstream - intravascular hemolysis
Hemoglobinuria, pigment nephropathy
Can give penicillin but prognosis is poor
Control liver flukes (Clostridium vaccine ineffective)
Bovine ulcerative lymphangitis
Bovine pyelonephritis
Corynebacterium renale
Bovine leptospirosis
Chlamydiosis
Campylobacteriosis
Brucellosis
Q-fever
Coxiella burnetti
mycoplasma hyosynoviae
Turkey coryza (bordetellosis)
Infectious coryza (chickens)
Avibacterium paragallinarum
Poultry Mycoplasmosis
Mycoplasma gallisepticum
Poultry chlamydiosis (psittacosis)
Clostridium botulinum
