Bacterial Enteritides Flashcards
Colibacillosis
E. coli, gram - rod shaped bacterium, found in intestine of animals
Enterotoxigenic (ETEC)
Releases enterotoxins → body to excrete fluids into the intestine
Adhere to/ colonize the absorptive epithelial cells → secretory diarrhea
Enteropathogenic (EPEC)
Don’t produce enterotoxins
Attachment and effacement of epithelial villi by bacteria
Alterations in ion/fluid transport →malabsorbtive and maldigestive diarrhea (bloody)
Other forms of colibacilosis
Enterohemorrhagic (EHEC): invade enterocytes → hemorrhage
Enteroinvasive (EIEC): invades lamina propria → septicemic colibacillosis
Predisposing factors of colibacillosis
Heavily contaminated environment
Failure to receive colostrum
Milk substitutes
Cold stress
Overcrowding
Concurrent infections
What are the different forms of colibacillosis?
ETEC (neonates/ pre weaning)
Post weaning colibacillosis (ETEC or EPEC)
Septicemic (fibrinous polyserotitis, meningitis, etc)
Edema disease (Shiga/ verotoxigenic E coli)
Lesions associated with EPEC
Vascular congestion
Fluid accumulation within the lumen
Hemorrhagic
Edema disease
Pig 6-14 wks old→ dietary changes
Fibrinoid necrosis of arteries/ arterioles
Neurologic signs and no diarrhea
CS with edema disease
Generalized edema (stomach, intestines, GB, skin, eyelids)
Cerebral edema with neuronal necrosis → swine cerebral angiopathy
Postweaning colibacillosis
Coliform enteritis of weaned pigs
In the first 1-2 weeks following weaning (change of food)
Loss of condition
Septicemic colibacillosis
Generalized systemic infection with E. coli (calves and piglets)
Peracute to chronic (bacterial localization in meninges, joints and body cavities)
Consequenses of septicemic colibacillosis
Hypogammaglobinemia
Fibrin thrombi
Hydropericardium
Fibrinous polyserositis
Salmonenllosis
Feco-oral transmission → invade enterocytes and macrophages → enteritis, septicemia and endotoxemia
“Second great pretender”
Peracute Salmonellosis
S. Cholerasuis
Petechial hemorrhage, DIC
Fibrinoid necrosis of BVs → thrombosis → ischemia, cyanosis and fibrinous polyserositis
Acute Salmonellosis
Fibroinonecrotic enterocolitis, necrosis of Peyer’s Patches and mesenteric lymphadenopathy
Multifocal hepatitis (paratyphoid nodules)
Chronic salmonellosis
Vasculitis → thrombosis → infarction → button ulcers
Ulcerative enterocolitis and proctitis
Rectal strictures and obstruction
Clostridial enteritis
C. perfringens: Enterotoxemia
Sudden death in healthy animals
Necrotizing/ hemorrhagic enterocolitis and toxemia
Gram+, rod shaped
C. piliforme
Tyzzer’s disease → necrotic hepatitis, enteritis, colitis and myocarditis
Affects horses and rabbits
C. difficile
Clostroides difficile
Horses: Abx- associated and nosocomial diarrhea
Other forms of clostridial infections
C. Chauvoei (blackleg)
C. septicum (braxy) → abomastitis in sheep and calves
Johne’s disease
Mycobacterium avium paratuberculosis (MAP)
Acid fast, Gram+
Zoonotic potential
Lesions of the advanced infection of Johne’s disease
Prominent mucosal folds (lepromatous form)- cattle
Caseating granulomas (tuberculoid form)- sheep goats and deer
Granulomatous lymphangitis and lymphadenitis
Lymphangiectasia
Distal ileum (ileocecal valve)
Lawsonia intracellularis
In pigs > 4 weeks
Hyperplasia of the crypt epithelium followed by crypt necrosis (ileum)
Synonyms for Lawsonia
Proliferative enteropathy (PE)
Proliferative hemorrhagic enteropathy
Swine dysentery
Brachyspira hyodysteneriae or B. hampsonii
Gram-, anaerobic spirochete
Affecting colon in pigs 8-14 wks old
Which anaerobic colonic flora does B. hyo (swine dysentery) interact with?
F. necrophorum
Bacterioides vulgatus
Swine dysentery findings
Fibronecrotic pseudomembranes
Hemorrhage
Necrosis of superfical mucosa
stain with Warthin-starry
Rhodoccus Equi enterocolitis
In foals 4-6 mon
Gram+
Suppurative/ pyogranulomatous pneumonia
Pyogranulomatous enterotyphlocolitis
