-
histophilus somni
- gram negative facultative anaerobe bacillus
- commensal of respiratory tract
- transmission by inhalation
- thrombotic meningoencephalitis
- neuro signs in calves (Stress, fall/winter) - recumbent, ADR, ataxia, knucking, crossing over
- multifocal hemorrhagic necrosis in brain
- dx at necropsy (lesions, tissue, blood agar)
- IV abx (oxytetracycline)
- bacterin vaccine for partial protection
-
Listeria monocytogenes
- gram positive facultative anaerobic bacillus
- widespread in nature, transmitted by ingestion, likes cold temps
- "circling disease", encephalitis, unilateral. See ataxia, circling to one side, head tilt, unilateral facial paralysis, dropped ear, head pressing, delirium, fever, anorexia, depression
- ZOONOTIC
- Ingested bacteria cross mucosal epithelium, taken up by MACROPHAGES, membrane-damaging toxin, use actin as a rocket-ship to go through cytoplasm and infect another cell.
- Replication within the cell is what causes damage.
- dx on brain tissue in the fridge for 12 weeks, or beta-hemolytic on blood agar in 24h
- sensitive to abx but also remove poor-quality silage.
-
streptococcus suis
- gram positive coccus in short chains, encapsulated
- type 2 capsule associated with meningitis
- can't survive extended in environment
- transmission by inhalation direct contact, fomites
- septicemia, arthritis, pneumonia, meningitis
- STRESS (post-weaning piglets - fever, anorexia, depression. Can have incoordination, paddling, recumbency, spasms, convulsions)
- Zoonotic
- blood agar, alpha hemolytic or antiserum for serotype. Mass-medicate animals during outbreaks (resistance to penicillin unlike most strep), reduce stress, bacterin vaccine (that doesn't work).
-
clostridium tetani
- gram positive spore-forming bacillus, obligate anaerobe, terminal spores (incredibly resistent, tennis racket)
- commensal/environment, not usually an intestinal problem, enters through deep punctures (anaerobe). Stay localized.
- toxin causes disease, not bacteria. Spastic paralysis (prolapse of third eyelid, muscle stiffness and tremor, lockjaw, sawhorse posture, resp. arrest). Conscious throughout.
- spores in deep wounds germinate in anaerobic conditions. produce neurotoxin (tetanospasmin). Transported in motor neurons to CNS. Blocks release (SNARE) of inhibitory neurotransmitters from inhibitory neurons = spastic.
- vaccine for toxoid (hapten).
-
clostridium botulinum
- gram positive, SUB-terminal (not as resisitant) spore-forming, anaerobic bacillus
- natural inhabitant of soils
- acquired by ingestion of TOXIN not bacteria, so INTOXICATIONBotulism = flaccid paralysis (toxin goes to presynaptic neuromuscular junction, SNARE blocks ACh release), muscle incoordination leading to recumbency, limberneck, chewing/swallowing difficulties
- Shaker foal syndrome (INFECTION via ingestion of bacteria) - C.botulinum type B, toxin produced in intestines. Waves of muscle tremors, fall down, difficulty in rising.
- Would botulism (infection, spores in a wound, rare)
- purge to remove toxin from GI tract, antitoxins for type B, abx (only shaker foal), debride wounds
- toxoid vaccine, counter phosphorus or protein deficiency
-
shaker foal syndrome
- infection with clostridium botulinum type B bacteria (subterminal spores, gram positive, anaerobic bacillus), spores germinate in intestines and produce toxin that crosses intestinal wall
- muscle tremors, falling down, difficulty rising
- treat with abs (and antitoxin)
-
wound botulism
- rare
- clostridium botulinum (gram positive anaerobic bacillus with sub-terminal spores) spores into a wound.
-
cryptococcus
- yeast, divides by budding
- C. neoformans (bird droppings), C. gattii (decaying wood)
- inhalation, spores small so get to alveoli, spread to CNS. Systemic in host as facultative intracellular pathogen of macrophages (polysaccharide capsule inhibits iNOS, melanin and mannitol scavenge free radicals), multiplies in and out of cells. Fungal growth induces inflammatory, both cause damage. Dx with CSF, narrow based buds on encapsulated yeasts.
- Neuro and eye (blindness, depression, seizures, circling, head pressing, ataxia, loss of smell)
- ulcerative lesions of mucous membranes of nose, mouth, pharynx (skin of nose and head)
-
fusobacterium necrophorum
- gram negative obligate anaerobic bacilli (beaded filaments of varying lengths)
- commensal of mucuous membranes
- Calf diptheria: foul breath due to necrotic swelling in oral or laryngeal (necrobacillus), ADR, cough in laryngeal
- Bullnose: necrotic rhinitis in swine (injury to face/oral/nasal causing necrotic cellulitis, depression of food intake).
- anaerobic blood agar culture, abx effective. IMPROVE HYGIENE
-
actinobacillus lignieresii
- gram negative, coccobacillus, facultative anaerobe
- Commensal of upper GI
- endogenous infections
- common in cattle, rare in sheep, dogs, horses
- wooden tongue: excessive salivation, difficult mastication, decreased food intake, granulomas make tongue swollen and hard, nodules along lymphatics, enlargement of local LN, purulent discharge containing "sulfur bodies"
- avoid introduction, tx with abx and iodine
-
candida albicans
- oval budding yeast on mucous membranes, pseudohyphae or hyphae (dep. on temp, pH, nutrition etc)
- Commensal of MM, endogenous infections
- Thrush/avian candidiasis: white circular raised ulcers (thrush is anterior digestive tract), unsatisfactory growth, stunted appearance, listlessness, rough feathers
- enteritis: white circular raised lesions in GI, diarrhea
- birds get copper sulfate in H20, everyone nystatin in food
-
enterobacteriaceae
- family of gram negative bacillus, facultative anaerobes.
- Natural inhabitant of intestines, widely distributed in environment
-
escherichia coli
- family enteroacteriaceae: gram negative bacillus, facultative anaerobe, commensal of intestines, in environment
- fecal-oral transmission
- includes enterotoxigenic (ETEC), Shiga-toxin-producing (STEC and enterohemorhhagic (EHEC)), septicemic (SEPEC)
-
ETEC
- family enteroacteriaceae ENTEROTOXIGENIC escherichia coli: gram negative bacillus, facultative anaerobe, commensal of intestines, in environment, fecal-oral transmission
- diarrhea in young (neonate and weanling pigs, neonate calves, lambs and puppies)
- secretory diarrhea (watery, dehydration, fluid imbalance
- species-specific pili - adhere to intestinal epithelium then produce enterotoxins (heat labile, heat stable) that cause secretion of electrolytes and fluids into lumen.
- Supportive for D, susceptible to abx, hygiene/management
- subunit vax for late pregnancy (pili and inactivated LT), anti-pilus-serum for newborn calves
-
STEC and EHEC
- family enteroacteriaceae SHIGATOXIN-PRODUCING AND ENTEROHEMORRHAGIC escherichia coli: gram negative bacillus, facultative anaerobe, commensal of intestines, in environment, fecal-oral transmission.
- Pili, shigatoxin-producing.
- STEC: mucoid hemorrhagic diarrhea, often recurrent, dehydration, weakness, decreased growth, edema disease in pigs. Pili in SI produce toxin
- EHEC: hemorrhagic diarrhea and hemolytic uremic syndrome in HUMANS, rarely in calves. ZOONOTIC. Pili in colon
- look for toxin on cultured, ELISA for toxin, PCR for toxin gene
- sensitive to abx, don't treat EHEC b/c stress releases toxin, makes worse. Toxiod vaccine
-
edema disease
- shigatoxin-producing e coli (STEC) in recently weaned pigs (receptor not there previously)
- 90% mortality, found dead
- rarely diarrhea, usu ataxia, paddling, recumbency and SQ EDEMA OF HEAD AND NECK
- pili adere to SI, adherent produce protein synthesis-inhibiting toxin (Shiga toxin). Kills intestinal epi- and endothelial cells (hemorrhage)
- infection spreads to bloodstream, damages small arteries and arterioles causing edema of head and neck, presses on nerves to prevent bloodflow = neuro symptoms and death.
-
SEPEC
- family enteroacteriaceae SEPTICEMICescherichia coli: gram negative bacillus, facultative anaerobe, commensal of intestines, in environment, fecal-oral transmission
- bacteremia in calves/lambs/piglets/foal
- fever, depression, weakness, +/- diarrhea. Rarer, meningitis, pneumonia, arthritis (tachycardia, labored breathing).
- Zoonotic.
- culture from normally sterile sites (blood etc)
- supportive care, some abx
-
Salmonella enterica
- Newborns: septicemia with depression, dullness, prostration, high fever, rapid death
- weanlings: acute enteritis with fever, fluid diarrhea with mucus (+/- bloody, tenesmus), anorexia, dehydration
- important in cattle and swine, opportunistic in horses, outside of US (REPORTABLE) in chickens, turkeys. Prob in d/c, gets into human through food contaminated with feces
- induces own uptake into epithelial cells (pathogenicity island), facultative intracellular in macrophages (avoid lysozomes via path island), induces inflammation causing diarrhea and promoting salmonella environment over commensal flora. Inflamm causes diarrhea.
- antimicrobials only early.
- Bacterin, subunit, attenuated vax
-
yersinia enterocolitica, yersinia pseudotuberculosis
- zoonotic
- enteritis, mesenteric lymphadenitis
- grow at low temps (fridge)
- EATING CONTAMINATED PORK, raw milk
-
campylobacter jejuni, campylobacter coli
- gram negative microaerophilic curved bacillus
- commensal of GI
- fecal-oral transmission
- gastroenteritis (range of D)
- zoonotic
- lots of poultry, young c/d. VERY common cause of D
- usu self-limiting, supportive care and hygiene
-
lawsonia intracellularis
- obligate intracellular gram negative curved bacillus (misdiagnosed as campylobacter)
- fecal-oral from sub-clinical, often
- porcine proliferative enteritis, ileitis, equine proliferative enteropathy (garden hose gut) (different strains for different hosts)
- chronic (anorexia, dullness, apathy, loose stools, progressive weight loss) or acute (hemorrhagic anemia, rapid death, melena)
- can't be grown on regular media, need PCR or immunofluorescence. Sensitive to abx, live attenuated vax (pigs, maybe horses)
-
garden hose gut (equine proliferative enteropathy)
- lawsonia intracellularis
- obligate intracellular gram negative curved bacillus (misdiagnosed as campylobacter)
- also porcine proliferative enteritis, ileitis (different strain)
- fecal-oral from sub-clinical
- chronic (anorexia, dullness, apathy, loose stools, progressive weight loss) or acute (hemorrhagic anemia, rapid death, melena)
- can't be grown on regular media, need PCR or immunofluorescence.
- Sensitive to abx, live attenuated vax (pigs, maybe horses)
-
porcine proliferative enteritis, ileitis
- lawsonia intracellularis
- obligate intracellular gram negative curved bacillus (misdiagnosed as campylobacter)
- fecal-oral from sub-clinical
- also equine proliferative enteropathy (garden hose gut) (different strains for different hosts)
- chronic (anorexia, dullness, apathy, loose stools, progressive weight loss) or acute (hemorrhagic anemia, rapid death, melena)
- can't be grown on regular media, need PCR or immunofluorescence.
- Sensitive to abx, live attenuated vax (pigs, maybe horses)
-
bradyspira
- gram negative oxygen tolerant anaerobic loosely coiled spirochetes, motile via periplasmic flagella (so doesn't stimulate TLR-5)
- commensal of digestive
- fecal-oral transmission
- Bradyspira Hyodysenteriae is swine dystentery, causes mycohemorrhagic D
- bradyspira pilosicoli is mild persistent D, ZOONOTIC
- metro for dogs
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