Topic 116 - Fowl paratyphoid. Reduction of Salmonella carriage of poultry, salmonella reduction programs, and their control (RED)

Question 1

Occurrence of fowl paratyphoid

Answer 1

Worldwide, quite a frequent problem

Question 2

Causative agent of fowl paratyphoid:

Answer 2

Many different serotypes

S. Enteritidis
S. Typhimurium

Question 3

Is fowl paratyphoid a obligate or facultative pathogen?

Answer 3

Facultative

Question 4

Type of infection in case of fowl paratyphoid:

Answer 4

Horizontal, vertical and germinative

Question 5

Susceptible age of fowl paratyphoid:

Answer 5

Decreases with the age

Question 6

Route of infection in case of fowl paratyphoid:

Answer 6

Per os
Aerosol
Germinative

Question 7

Pathogenesis of fowl paratyphoid:

Answer 7

1. there is an infection
2. Bacteria settles in the gut, causing damage to the gut epithelium and lymphoid organs
3. in some cases, in very young chickens, it can cause septicaemia
4. Bacteria reaches the parenchymal organs

Question 8

Clinical signs of fowl paratyphoid:

Answer 8

YOUNG CHICKENS
Septicaemia
in duck and geese: purulent conjunctivitis, weak legs and incordination
Chicken: Becomes part of the normal gut flora

ADULTS
There are no clinical signs, excpet for in pigeon: Diarrhoea, CNS signs, arthritis

Question 9

How to diagnose fowl paratyphoid:

Answer 9

Bacterium isolation
PCR
ELISA
Serotyping
Sometimes detection of antibodies are useful

Question 10

Treatment of fowl paratyphoid

Answer 10

AB is generally not good, due to the high carriage of bacterium. It is important to eliminate predisposing factors

In EU: salmonella reduction projects and AB treatment is exceptional

Question 11

Prevention methods in case of fowl paratyphoid:

Answer 11

1. Hygiene ⭢ Collection of eggs, hatching, settlement, keeping
2. Excluding convalescent herds from breeding
3. Insect and rodent control
4. Probiotics
5. Reduction
6. Vaccines

Question 12

Type of vaccines used against fowl paratyphoid

Answer 12

Serotype specific vaccine against S. Enteritidis and S. typhimurium

We use live and inactivated vaccines, and the animals are continuously vaccinated

Question 13

Causative agent of asymptomatic salmonella carriage in chickens:

Answer 13

salmonella infantis

Question 14

Pathogenesis of asymptomatic salmonella carriage in chickens:

Answer 14

Limited to the intestinal tract
Simultaneously and periodically shedding of the salmonella

Question 15

Duties of the farmer in case of control of salmonella carriers in a Breeding flock:

Answer 15

1. On day 0 = Hatching papers are sampled
2. On week 4 = faeces are sampled ⭢ 5 boot samples or 1 boot sample + dust
3. 2 weeks before laying = Faces are sampled ⭢ boot samples
4. Every 2 weeks during laying = faecal sampling and dead eggs

Question 16

Official sampling methods in case of control of salmonella carriers in a Breeding flock:

Answer 16

1. First 4 weeks of laying
2. Middle of laying
3. Last 8 weeks of laying

Question 17

Duties of the farmer in case of control of salmonella carriers in a Laying flock:

Answer 17

1. On day 0 = Hatching papers are sampled
2. 2 weeks before laying= faeces are sampled ⭢ 2 pairs of boot samples
3. Every 15 weeks

Question 18

Official sampling methods in case of control of salmonella carriers in a Laying flock:

Answer 18

If a farm size is bigger than 1000, we test one flock per farm with collection of 2 pair of boot samples and dust

Question 19

Duties of the farmer in case of control of salmonella carriers in a Broiler flock:

Answer 19

Send faecal boot sample within 3 weeks of slaughtering

Question 20

Official sampling methods in case of control of salmonella carriers in a Broiler flock:

Answer 20

If herd size is bigger than 5000, we test 10% of the farms per year, we collect 2 pairs of boot samples

Question 21

How do we evaluate the samples sent in from the farmers in case of salmonella carriers:

Answer 21

The whole process takes 5-6 days !!

1. Pre-enrichement = 18-24 hours to make them detectable
2. Selective enrichement = 24 hours
3. Plating and incubation = 24 hours
4. Biochemical tests = 48-73 hours