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Flashcards in Test 2- Salmonella Deck (31)
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1
Q

Salmonella General

A
  • Obligate symbiotic
  • Virulence

————— Host specific serotypes (typhoid)

————————— Eg.S.Typhi;S.Gallinarum

————— Host adapted/restricted serotypes

—————————– S. Dublin: bovines

—————————-S. Typhimurium var. Copenhagen: Pigeon

• Non host specific serotypes

  • Most serotypes, eg. Typhimurium, Enteriditis, Virchow, Agona, Paratyphi B,…
  • Quite resistant in environment
  • Especially
  • when protected by organic material (feces)
  • In a dry environment (dust, feed) need Control programs
2
Q

Salmonella General, Zoonotic aspects

A

• zoonotic

  • Non host specific
  • Some host adapted/restricted

• Not zoonotic

  • Host specific
  • Some host adapted/restricted

• Antimicrobial resistance and the zoonotic aspect are a matter of concern

3
Q

Salmonella: Pathogenesis

A
  • Facultative intracellular- can avoid the immune system
  • Differences in pathogenesis between
  • Host adapted (typhoid) + host restricted
  • Non host adapted
4
Q

Salmonella and bovines Symptoms

A

• Different serotypes possible but mainly: S. Typhimurium and S. Dublin

  • S. Typhimurium
  • Diarrhea (Ileum and large intestine) + general symptoms • (Tissue localization )
  • Abortion
  • Udder

• S. Dublin

  • Calf
  • (Diarrhea)
  • General symptoms
  • Tissue localization: lung, liver, spleen,…

• S. Dublin, adult cattle

  • (diarrhea), general symptoms
  • Organ dependent symptoms
  • Abortion
  • Subclinical mastitis (persisting intracellular)
5
Q

Salmonella and bovines Diagnosis

A

• Live animals

  • Fecal material
  • Milk (in case of subclinical mastitis)
  • Respiratory: BAL
  • Arthritis: puncture
  • Abortion: fetus, placenta, vagina

• Dead animals

  • Ileum
  • Different organs
6
Q

Salmonella and bovines Treatment

A
  • Isolation of sick animals
  • Fluid therapy
  • Antimicrobials
  • NSAID
7
Q

Salmonella and pigs

A
  • S. Choleraesuis: Typhoid
  • Non host specific Salmonella
  • Clinical symptoms in animals >50kg, most freq subclinical
  • Diarrhea + general symptoms
  • Slowspread
  • Hyperacute form (>70-80 kg), acute mortality
  • Acute form freq + cyanosis
  • Chronicform:nonspecific,lessergrowth
  • Zoonotic
  • Mainly

• S.Typhimurium

  • S.Derby •…
  • Carriers
8
Q

Salmonella and pigs Dx and Tx

A
  • Diagnosis
  • Bacteriological culture
  • ELISA (Antigen)
  • ELISA (antibodies) but difficult interpretation
  • Used sometimes in control programs
  • Treatment
  • Antimicrobials
  • Eventually general support (NSAID,…)
9
Q

Salmonella and pigs Prevention

A
  • Prevention
  • Management: AI-AO, cleaning and disinfection,…
  • Organic acids in the FEED/ WATER

—————Short chain fatty acids

—————Medium and long chain fatty acids (more antibacterial)

—————In drinking water (pH 3.6-4.1)/feed

—————Coated: delivery in Ileum and large intestine

  • Feed composition (particle size large: protective by pH stomach due to slower transit)
  • (vaccination)
10
Q

Salmonella in horses Salmonella Abortus-equi

A

• Salmonella Abortus-equi:

—————Rare

• Pathogenesis depends on uptake

11
Q

Salmonella in horses Dx, and Tx

A

• Diagnosis

————— Bacteriology

• Treatment

—————Antimicrobials

————— Elimination from reproductive organs is difficult (bacteria is intracellular)

12
Q

Salmonella in horses Non host specific Salmonella Pathogenesis and Symptoms

A
  • Pathogenesis: cfr. general slide
  • Short incubation period(hours-6days) Symptoms
  • Clinical/subclinical
  • Clinical:
  • Mild
  • Acute
  • Hyperacute
  • Chronic
  • Localization
13
Q

Salmonella in horses Symptoms • Clinical salmonellosis MILD FORM

A
  • Mild form
  • General symptoms (fever, anorexia, depression)
  • Slight diarrhea
  • Diagnosis difficult (isolation from feces frequently unsuccessful)
  • Self-limiting
14
Q

Salmonella in horses Symptoms • Acute form (most frequent)

A

• Acute form (most frequent)

  • Fever, anorexia, mild colic
  • 24h: diarrhea
  • Severe symptoms + cyanosis
  • Shock possible- DUE TO LPS
  • Laminitis (hoof)
  • Slow recovery + relapses possible
  • Can evolve to chronic
  • Intermittent diarrhea
  • Intermittent anorexia
  • Weight
  • Intermittent fever
15
Q

Salmonella in horses

• Hyperacute and tissue localization

A
  • Hyperacute
  • Foal
  • Sever general symptoms
  • Eventually diarrhea
  • Endotoxic shock (24-72h) which leads to death

Tissue localization

  • Foal
  • Clinic depending on the organ affected
  • Freq arthritis
16
Q

Salmonella in horses Dx, therapy, treatment

A

• Diagnosis

  • Neutropenia
  • Culture

• Therapy

  • Hydration: IV
  • Shock: NSAID (no cortico’s  hoof laminitis)
  • Antimicrobials
  • Carriers!!!

• Prevention

• Hygiene

17
Q

Salmonella in cats and dogs

A
  • Non host specific serovars
  • Enteritis and septicaemiae
  • Carriers
  • Dogs: 0-36%
  • Cats: 0-20%

• Origin: mainly feed

  • Diagnosis
  • Culture
  • ELISA
  • PCR
18
Q

Salmonella in cats and dogs • Treatment

A
  • Treatment
  • Hydration
  • Antibiotics:
  • contraindicated in animals with a good general condition (creation of carriers!!!)
19
Q

Salmonella in pigeons: Paratyphus

A
  • S. Typhimurium var. Copenhagen
  • Specific clonal lineage
  • PT 2 and 99
  • Not zoonotic
  • Carriers are cause of spread
  • Systemic disease + diarrhea
  • Acute paratyphus
  • Mainly during breeding
  • Chronic
  • One wing is hanging down (tissue localization)
  • Intermittent excretion
20
Q

Salmonella in pigeons: Paratyphus • Symptoms (in a flock)

A
  • Symptoms (in a flock)
  • Anorexia
  • Weight
  • Diarrhea • Limping • Unable to fly • Breeding difficulties • Apathic • Polyuria - polydipsia • mortality
21
Q

Salmonella in pigeons: Paratyphus Dx, and tx

A
  • Diagnosis • Bacterial culture • Rapid slide agglutination for antibodies
  • Treatment • Antimicrobials (strains are very susceptible!) • Immune therapy: inactivated vaccine • Not prevention of infection • Reduction of severity of disease • Hygiene
22
Q

Salmonella in psittaciformes and passeriformes

A

• Psittaciformes • Very rare • Passerformes: S. Typhimurium (other clone than Columbiformes) • In birdhouses • Stress • Overcrowding • Cold & humid • Inappropriate feeding • Symptoms: DD. rodentiosis (Yersinia pseudotuberculosis) • Apathic, feed and water intake • Chronic • Diarrhea (most of the time)

23
Q

Salmonella in Poultry Typhoid/paratyphoid Non-typhoid

A

• Typhoid/paratyphoid Salmonella

  • S. Pullorum
  • S. Gallinarum

• Non-typhoid Salmonella

  • S. Enteriditis
  • Other: • Typhimurium • Virchow • Paratyphi B • Infantis • Agona,… • Newport(US) • Quite complex and variable epidemiology
24
Q

Typhoid Salmonella in poultry • S. Pullorum/Gallinarum

A
  • S. Pullorum/Gallinarum
  • Antigenically same (1, 9, 12:-: -)
  • Antigenically similar to S. Enteriditis (1, 9, 12:g,m:-)

—————Vaccination against SE gives false positives in serology

• Biochemical differentiation (evt. PCR)

• REPORTABLE disease- typhoid salmonella

  • Official elimination programs (now rare disease in Europe and North America)
  • Turkeys: S. enterica ssp. arizonae
25
Q

Typoid Salmonella in poultry • S. Pullorum

A
  • S. Pullorum
  • Pullorum disease
  • Chicken, turkey, pheasant
  • Younger animals
  • High mortality • Acute sepsis
  • General symptoms
  • Differences in virulence of the strains
  • Typical granulomatous lesions stomach, liver and myocardium • Adults: oophoritis with deformed yellow-greenish follicles

• Survival: carriers
• Horizontal and vertical transmission

• Vertical: mortality peak: 2-3 wks

26
Q

Typhoid Salmonella in poultry Dx and treatment

A

Diagnosis

  • Bacterial culture
  • Serology: slide agglutination
  • Care: cross reactivity with SE vaccination
  • False positives due to Streptococci Lancefield D,…, ? •

Treatment

• Only for hobby poultry: antibiotics, but no elimination (intracellular) • Reportable

27
Q

Typoid Salmonella in poultry • S. Gallinarum: fowl typhoid

A
  • S. Gallinarum: fowl typhoid
  • Chickens, ducks, pheasant, quail, partridges, turkeys
  • Serological cross reactive with S. Pullorum
  • Older animals

• REPORTABLE

• Symptoms • Hyperacute mortality + hemolytic anemia (endotoxins) • Acute and subacute; increasing mortality up to 30%, general symptoms

28
Q

Typoid Salmonella in poultry • Turkeys: S. enterica ssp. arizonae

A
  • Turkeys: S. enterica ssp. arizonae
  • Mainly in the USA
  • Different serotypes
  • Only younger animals
  • General symptoms with mortality up to 50%
  • Diagnosis: culture
  • Treatment- Best eradication
  • Control by serology (slide agglutination): difficult
  • Different serotypes
  • False negatives
29
Q

Paratyphoid Salmonella in poultry • S. Enteriditis

A
  • Zoonotic (egg contamination)
  • Consumption of undercooked, raw egg
  • Used to be the most frequent serotype causing zoonotic infection
  • Decreased enormously due to vaccination
  • Vaccination is imposed legally in Europe (not in the US)
  • Eggs from positive laying flocks can only be used after heating
30
Q

Paratyphoid Salmonella in poultry • Other serotypes

A

• Other serotypes

  • Geographical differences in prevalence of different serotypes
  • Differences in time (evolution)
  • Many are serotypes are zoonotic
  • EU: breeding animals must be free of Enteriditis, Typhimurium, Virchow, Hadar, Infantis, Paratyphi B var. Java
  • 30% broilers are positive
  • At slaughter, up to 80% positive (cross contamination)
  • In US, decontamination of carcasses with bleach (not allowed in EU)
31
Q

Paratyphoid Salmonella in poultry • Other serotypes

A
  • Other serotypes
  • No vertical transmission
  • No clinical symptoms, unless
  • Very young infected with high dose
  • Aflatoxins in feed
  • T0 too low for young animals (should be 320 for one day old)
  • Other enteric infections(eg.Eimeriatenella)
  • Stress (transport

) • Remediation in positive flocks (no elimination)

  • No vaccine
  • Pro-, prebiotics
  • Fatty acids