Bacterial respiratory diseases in poultry Flashcards
FC stands for
fowl cholera
fowl cholera is also known as
pasteurellosis
Pasteurellosis, fowl cholera (FC), is a highly contagious bacterial disease of wild and domesticated birds, characterized by
pneumonia, septicemia and sudden deaths.
causative agent of fowl cholera?
genus, family, details?
Gram– bacterium Pasteurella multocida
Genus Pasteurella, family Pasteurellaceae
nonmotile, relatively short rod-shaped bacterium
Present in the oral cavity of dogs and cats.
Can stay infectious for several weeks in the environment.
ZOONOSIS
Subspecies of pasteurellosis/fowl cholera
Three subspecies:
ssp. multocida,
ssp. septica ja
ssp. gallicida
Present in the oral cavity of dogs and cats.
Can stay infectious for several weeks in the environment.
How are the different pasteurella strains divided?
Different strains, divided into serogroups
(A, B, D, E, F) →
different pathogenicity
Host range and age for fowl cholera.
Diagnosed in wild and domesticated birds and in most animals too. More often in late summer, autumn and winter.
Chicks and young layers especially sensitive.
Source of infection: sick or latent carrier birds.
Carrier status is for life – excrete the pathogen intermittently.
Explain why fowl cholera is of economic importance. (5)
High mortality
Losses in weight gain, weight loss and drop in egg production.
Low quality carcasses
High cost of treatment
Prevention is difficult: many ZOONOSIS! serotypes.
Transmission of fowl cholera.
Excretion: feces, nasal secretions
Transmission: direct contact, fecal-oral, predatory attacks, alimentary, aerosols.
Course of disease in fowl cholera.
either acute pasteurellosis or chronic
Clinical signs of acute pasteurellosis in poultry.
Acute septicemia, sudden deaths.
highly morb. + high mort.
Clinical signs of chronic pasteurellosis in poultry.
presents as localized infection: joint swelling, or sternal bursa swollen, ears, sinuses or wattle
mucous from the beak, apathy, limping, torticollis, emaciation.
low mort.
Post mortem signs of acute pasteurellosis in poultry.
general hyperemia
hematomas, petechiae
organ swelling or enlargement
coagulative necrosis of liver
Post mortem signs of chronic pasteurellosis in poultry.
localized purulent inflammation in diff. organs
peritonitis
hepatitis
pneumonia
caseous exudate in middle ear or elsewhere
diagnosis of fowl cholera
Material: liver, spleen, lungs, wattles,
joints, feces, blood, nasal secretion.
Methods:
Bacteriological study → culture from the
carcass or nasal swab.
Gram staining, ELISA, PCR-based methods
Treatment of fowl cholera.
Treatment → based on antibiogram!
Sulfonamides, penicillins, aminoglycosides, tetracyclines, fluoroquinolones.
Multi-resistance can occur!
Prevention of fowl cholera.
Prevention: reducing stress, good hygiene, biosecurity.
Avoiding rodents, wild birds and other animals and their feces, avoiding visitors, „all in/all out“ system, buying infection-free
birds.
Vaccination: attenuated live vaccines, with drinking water. However, they do not give full protection.
AIC stands for
Avian infectious coryza
Avian infectious coryza is usually an acute infectious disease of chickens, sometimes
pheasants and guinea fowls, characterized by
the presence of nasal secretions, swelling of the face, and catarrhal inflammation of
the upper respiratory tract.
Causative agent of avian infectious coryza.
genus, family, +details
agent Avibacterium paragallinarum, Av. gallinarum
Genus Avibacterium
family Pasteurellaceae
Gram–, pleomorphic, nonmotile bacterium
Microaerophilic, V-factor is needed for growth.
Catalase negative (important in diagnosing!)
serovariants of AIC
Three serovariants: A, B, C (based on Page scheme)
Host range and age demo for AIC.
Prevalent all over the world, in chickens of any age.
In developed countries → young birds and layers.
In developing countries → in chicks from 3 weeks of age.
The risk of infection is higher in older birds.
Reservoirs: chronically ill and carrier birds.
Transmission of AIC.
Transmission: direct contact, contaminated drinking water, no vertical transmission.
Risk factors: poor biosecurity, poor environment and other diseases.
IP of AIC
Incubation period: 1-3 days,
the disease lasts 2-3 weeks.
Mortality of AIC.
Mortality 20-50%, usually not more than 20%.
Course of disease in AIC.
acute & chronic
Clinical signs of acute AIC.
Depend on the severity of the case.
depression, anorexia, epiphora, conjunctivitis, sinus edema, decrease in production, dyspnea, nasal secretions, sneezing, diarrhea
specific to acute: infraorbital sinus swelling/inflammation, gray nasal secretions
Clinical signs of chronic AIC.
Depend on the severity of the case.
depression, anorexia, epiphora, conjunctivitis, sinus edema, decrease in production, dyspnea, nasal secretions, sneezing, diarrhea
specific to chronic: thick yellow nasal discharge, rotten smell, secondary infections
Post mortem signs of acute AIC.
infraorbital sinus pathology and nothing else, catarrhal inflammation in this site.
gray semifluid nasal exudate
swelling of face and eyes