Dr. Stanley Kleven · Fowl Typhoid A septicemia, seen primarily in chickens, also in turkeys, and...

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Transcript of Dr. Stanley Kleven · Fowl Typhoid A septicemia, seen primarily in chickens, also in turkeys, and...

Fowl Typhoid

A septicemia, seen primarily in chickens, also in turkeys, and other avian species. It looks very similar to pullorum disease.

This is common internationally due to lack of eradication programs.

This disease can continue for months and can be seen in young adults or mature fowl, due to the stress of coming into production.

Dramatic drop in outbreaks since NPIP – (1954).

Reportable.

Causative Agent

Bacteria, Salmonella gallinarum

Closely related to S. pullorum but

biochemically different.

S. pullorum & S. gallinarum: Antigenically

identical (complete cross agglutination) (S.

enteritidis also cross-agglutinates).

Method of Spread

Lateral from carriers

Vertical from carriers

Transovarian

Rats and feral birds (buzzards)

Human traffic

Incubation Period 4 to 5 days

Course of Disease 5 days in acute cases.

Losses may extend over

2-3 weeks period.

May recover.

Mortality If acute may range up to 50%.

Variable.

Clinical Signs

Chicks and Poults – Similar to pullorum

Infected eggs yield moribund and dead chicks

Whitish pasty vents

Anorexia

Labored breathing

Clinical Signs

Growing and Mature Birds

Drop in feed consumption

Depressed and pale

High fever (up to 112ºF)

Normal body temperature – 104ºF

Greenish diarrhea – catarrhal enteritis

Death in 4 to 10 days after exposure

Paleness, depression

Emaciation

Postmortem Lesions

Same as pullorum with a tendency for

enlarged (2-3x) dark spleens in acute

cases and mahogany or greenish-bronze

livers in subacute and chronic cases.

Focal areas of necrosis in the heart and

grayish lungs are also apparent.

Comment

This disease is usually very acute, and

dead birds will be found on the nest and

on the floor.

These birds may not have lesions.

Mahogany Liver

Liver necrosis

Liver & spleen lesions

Bronze liver

Congested liver, atresia of ova

Congested spleen

Cecal cores

Differential Diagnosis

Abscesses in lungs and viscera in chicks

unique to typhoid and pullorum.

In adults similar to other septicemic

diseases.

Reaction to agglutination test helpful in

chronic cases.

Diagnosis

Suggestive Diagnosis – High mortality in

hens, showing described lesions.

Positive Diagnosis – Isolation and

identification of the causative agent from

liver and/or spleen.

A positive agglutination test to pullorum

antigen will aid in the diagnosis.

Whole blood agglutination

Control Program

Voluntary regulatory program reactors

must be disposed of under supervision of

state regulatory agency.

Flock usually destroyed.

Premises decontaminated as per the

NPIP.

Culture Methods

Similar to other Salmonellae except:

Slow to variable H2S production

Non-motile

S. pullorum and S. gallinarum and S.

enteritidis are Group D

Treatment

Same as S. pullorum treatment. I.

(destroy) & II. (treat to control mortality).

Prevention

An attenuated vaccine strain 9R of S.

gallinarum is being using with success in

some foreign countries that do not have

successful eradication programs.

This is not licensed in the U.S.