enterobacteriaceae lactose-fermenters

Klebsiella

• gram-negative rod

• Facultative anaerobes

• Non-hemolytic

• Mucoid colonies

• Usually non-motile (except K. aerogenes)

• Lactose fermenters

• Opportunistic pathogens

• klebsiella pneumoniae

• K. oxytoca

Klebsiealla most common pathogens in vet. med.

• klebsiella pneumoniae

• K. oxytoca

Klebsiealla most common pathogens in vet. med.

Coliform mastitis

Klebsiella pneumoniae

• _______ - cattle

Cervicitis and metritis

Klebsiella pneumoniae

• _________ - mares

Dogs

Klebsiella pneumoniae

• UTI -

Pneumonia and suppurative conditiojs

Klebsiella pneumoniae

• foals -

37˚C

Klebsiella

• Easily identified through routine diagnostic laboratory culture at _____

• non hemolytic

• Large

• Very mucoid

• Whitish gray

Klebsiella colonoies on blood agar are

Pink to red without red haze

Klebsiella colonoies on MacConkey agar are

Negative

Oxidase-

Indole-

capsular (K) antigens

Klebsiella species are serotyped by

77

____ capsular K antigens

• k1

• K2

• K5

_______ are venereally transmitted

• Predominant types in isolates from metritis in mares

Salmonella

The nomenclature of _____ is complicated and confusing

1980s

The taxonomical designation of species has undergone numerous changes since the late

serovars/serotypes

In addition to species and subspecies, Salmonella are grouped into ______ – currently over 2,600

Serovars

defined by the presence of surface antigens

O-antigens

based on the oligosaccharides associated with LPS

H-antigens

Based on flagellar proteins

Mono- or di- phasic

H- antigens

• strains may be

Two phases

H antigens

• can have

Intestinal tract

Salmonella natural habitat

• _________ of warm- and cold- blooded animals

• Many are subclinical excretors

• moist soils,

• water,

• fecal particles and

• animal feeds (bone, meat and fish meals

Salmonella can survive for 9 months or more in the

• state of colonization resistance of host

• infectious dose

• species or serotypes of Salmonella

Salmonella Transmission

• fecal- oral route

• Ingestion of contaminated food and water

  • Outcome of interaction of host and Salmonella depends on:

• disease may or may not occur after ingestion

Enteric Form

• Lesions in intestinal tract consist of fibrinosuppurative, necrotizing, and hemorrhagic inflammation of the distal small intestine and large bowel

• Necrosis of intestine is at first erosive → ulcerative → formation of diphtheritic membrane

  • Common in cattle and swine

Liver

_____ is affected with random, multifocal necrotizing inflammation that reflects bacterial spread and phagocytosis without effective bacterial killing

Septicemic Form

• Fibrinoid change in blood vessels in many different organs

• Vasculitis, thromboembolism, hemorrhages and infarcts

Swine with septicemic S. Choleraesuis infection

• Spleen is enlarged due to hyperemia

• Ears of white-skinned pigs may be dark blue from thrombosis and venous congestion

S. tymphimurium

Salmonella Dublin

• Host adapted to cattle

• Cause of severe disease in endemic herds

  • Septicemia in calves <1 week old

  • Acute enteritis in older calves and adults

  • Abortion in pregnant cows

  • Chronic enteritis in older cows (inappetence, ↓weight gain)

Terminal dry gangrene

Salmonella Dublin

• necrosis of feet

• cleaning calving areas, rodent control

• Vaccination possible

Salmonella dublin management

Salmonella dublina

Salmonella cholerasuis

• Host adapted to pigs, maintained by carriers

• Cause of:

  • Sepsis is most common manifestation

  • Enterocolitis

  • Secondary infections following bacteremia (pneumonia, hepatitis)

  • During acute disease large numbers shed in feces

• Reducing stress (housing density, nutrition, concurrent infectious diseases) can reduce shedding by carriers

• Autogenous bacterins may be helpful

Salmonella cholerasuis management

Salmonella cholerasuis

Salmonella pullorum

• Host adapted to birds

• Infects the ova and chicks are infected prior to hatching

• After hatching, environment is contaminated facilitating transmission

• Primarily affects young chicks and poults

  • Inappetence, depression, diarrhea, death

• Inappetence,

• arthritis,

• decreased production,

• diarrhea,

• pyrexia,

• increased mortality

Salmonella pullorum

• in older birds

Reservoir of flock

Birds which survive infection becomes

Salmonella pullorum

Salmonella Typhi

• Host adapted to humans

• Spread by contaminated food and water

• High fever, weakness, stomach pains, death

• Primarily travel associated

• Acquired by ingesting contaminated water or food

• Vaccination is possible and important

Slide Agglutination Test

The Salmonella is first tested against antisera to the O (somatic) antigens and then the H (flagellar) antigens.

• phase 1 (specific) flagellar antigens; or

• phase 2 (non-specific) flagellar antigens

Salmonella that are motile and diphasic will contain cells that

have either:

One phase

Majority have flagella in _______ but there will be a very few cells with the alternative flagellar antigen.

Craigie Tube Method and Ditch-Plate Method

These methods are used to select cells that have the alternative flagellar antigen

Nursing care

Enteric Form Treatment

• principal treatment

Controversial

Use of antibiotics is _______

• Studies show that antibiotics do not alter the course of the disease.

Salmonella Systemic Form treatment

Nursing care and antimicrobial therapy

• Ampicillin,

• enrofloxacin,

• trimethoprim-sulfonamides,

• chloramphenicol/florfenicol

• Since salmonellae survive in phagocytic cell, antimicrobial should be able to penetrate the cell.

4 or more drugs

Multiple resistance _____ is common

Salmonella typhimurium

Reported to have resistance to

• ampicillin,

• streptomycin,

• sulphonamides,

• tetracyclines and

• furazolidone

Salmonella genomic islands, integrons and plasmids.

Antimicrobial resistance is encoded by genes found as part of

Inter

transferable between Salmonella serotypes and can be responsible for combinations of multidrug resistance