Poultry Pathogens Flashcards
List the risk factors for bacterial infection in poultry
Risk Factors (FLAWLESS: feed/light/air/water/litter/energy/sanitation/security)
* Breeder hen health
* Hatchery sanitation
* Barn sanitation
* Waterline sanitation
* Poor ventilation
* Stress
List 3 main environmental problems in intensive poultry production.
- Poor ventilation = high ammonia/dust/bio-aerosols/CO2/humidity
- Crowing = injury/stress (reduce immune) /spread disease/poor access too food and water
- Poor litter quality = wet/release sulfur compounds/grow bacteria
List 3 ways the environmental problems can allow pathogen entry and what systems are affected
- Skin = cellulitis/dermatophytes/bumblefoot
- Resp = airsacculitis/pneumonia/tracheitis/conjunctivitis
o Irritate resp due to poor air quality = inflammation - GI = necrotic enteritis/enteritis/diarrhea
o High carb diet alter microflora
o Inflammation allows pathogen entry
List 5 ways bacterial pathogens are transmitted to poultry
- Humans
- Fomites
- Wind wild bird droppings
- Backyard bird feeders
- Direct contact
List 3 types of fungi that affect poultry
- Aspergillus spp
- Microsporum gallinae (dermatophyte)
- Candida albicans
What type of birds do ringworm affect mainly? What is the main causative agent? How is it treated/
- Microsporum gallinae (dermatophyte)
o Not zoonotic
o Show poultry/pet birds
o Tx with topical antifungals
What are 3 main diseases caused by aspergillus
- Aspergillus spp
o Brooder pneumonia
o Fungal air sacculitis
o Aspergillosis
What are 2 main diseases caused by candida albicans
- Candida albicans
o Crop mycosis
o Thrush
What are the main causative agents of systemic/GI/and resp poultry bacteria
Systemic
* E. coli
o Agent: avian pathogenic E. coli
* Salmonella
* Staph aureus
* Enterrococcus cecorum
* Mycoplasma synoviae
GI
* Salmonella
* Clostridium perfringens - Necrotic enteritis
Resp
* Bordatella avium
* Mycoplasma gallisepticum
* Ornithobacterium rhinotracheale
* P. multocida
* Avibacterium paragallinarium
* Chlamydia psittici
What type of E. coli affects poultry? What are the 2 main clinical signs or syndrome
o Agent: avian pathogenic E. coli
o Clinically: systemic
Colibacillosis
Hallmark: fibrinopurulent air sacculitis
What is colibacillosis? What causes it?
o Colibacillosis: localized and systemic infection
Most common disease of all poultry
Caused by stress or immune compromised birds
* Peak production/brooding period/heavy growth period/hygiene
What are the lesions of colibacillosis
Lesions
* Green discoloured liver - hepatitis
* Air sacculitis
* Cellulitis = swollen head syndrome
* Arthritis
* Polyserositis
* Pericarditis
* Peritonitis
* Salpingitis
* Osteomyelitis
How is colibacillosis diagnosed and what samples do you take
- Sample:
o Swab – exudate of yolk sac/air sac/pericardium/joint
o Tissue – heart/spleen/liver/lung/bone marrow - Test: C/S and virotying PCR
List 4 differentials for colibacillosis
- Salmonellosis
- Fowl cholera
- Erysipelas
- Staph
What is the causative agent for Yolk sacculitis/omphalitis and what are the risk factors
E coli
Risk factors
* Vertical trransmision
* Hatchery/truck/barn/water sanitation
What are the lesions associated with yolk sacculitis/omphalitis
Mortality in first week of life
Lesions
* Hyperemic yolk sacs and inflamed navels
What does salmonella cause systemically in poultry
- Salmonella
o Septicemia
What poultry are targeted by S. aureus? Where is it found? What is its impact?
- Staph aureus
o Target: chicken/turkey
Low morbidity and 15% mortality
o Commensal on skin
How is S. aureus transmitted
o Transmit:
Hatchery/farm environment and fomites
Enter via damaged skin and wounds (beak/toe trimming) then spread in blood
What are the risk factors associated with S. aureus
o Risks
Viral infection (reovirus)
Stress
Trauma
Nutritional deficiency
Immunosuppression
What are the clinical signs associated with S. aureus in poultry
o Clinically
Bumblefoot
Dermatitis
Folliculitis
Septic arthritis
Osteomyelitis
Tenosynovitis
Chondronecrosis
What are the clinical manifestations and lesions associated with S. aureus
Swollen hocks = lame/reluctant to walk
Retracted/splayed legs
Lesions: femoral head necrosis
How to diagnose S. aureus and what samples are needed
Sample
* Exudate from swollen joints
* Liver/spleen/kidney
Test; C/S
What are 5 differentials for S. aureus
Collibacillosis
Mycoplasma synoviae
Viral arthritis
Fowl cholera
Fowl typhoid
What is the gram type and shape of Enterrococcus cecorum? Where is it found?
- Enterrococcus cecorum
o Gram (+) cocci
o Ubiquitous
How is Enterrococcus cecorum transmitted
o Transmit: fecal oral
vertical or stress induced
What are the clinical manifestations of Enterrococcus cecorum
vertebral osteomyelitis
Septicemia
What are the clinical signs of Enterrococcus cecorum
o Signs
Posturing
Lameness
Reluctant to move
How is Enterrococcus cecorum diagnosed and what samples are taken
o Diagnose
Sample: bone/joint
Test: C/S
What are some considerations when treating Enterrococcus cecorum
o Tx: enterococci have intrinsic resistance to many drugs (ex. cephalosporins)
What are 3 differentials for Enterrococcus cecorum
S. aureus
E. coli
Mycoplasma synoviae
What is the main clinical manifestation of Mycoplasma synoviae
o arthritis
What is the gram type and shape of salmonella? How are the sub-species and serotypes distinguished
- Salmonella
o Gram (-) rod
o Many serotypes – 20 important for poultry
Sub-species divided into serogroups based off of somatic (O) antigens
Serogroups divided into serotypes based off of flagellar (H) antigens
Give 2 examples of host adapted salmonella. What is one important consideration
o Host adapted salmonella
S. pullorum = pullorum disease
S. gallinarum = fowl typhoid
Provincially and federally reportable (will cull whole flock)
What are the 3 causative agents of paratyphoid salmonella
o Paratyphoid salmonella
Agents; S. enteritidis/typhimurium/Heidelberg
What poultry types are associated with Salmonella pullorum
- Target: all birds (mainly chicken)
o 10-80% morbidity and high mortality in stressed/immunocompromised birds (if <3 weeks) - Rare in commercial production
How is Salmonella pullorum transmitted
- Transmit: transovarian/fecal oral
o Also yolk sac/cannibalism/wound/skin/food/water
o Persist in environment
What are the clinical signs of Salmonella pullorum
- Clinically
o Dead in shell chicks/death after hatch
o Non-specific signs: white diarrhea/dyspnea
Ruffled feather/depressed/anorexia
o Subacute = lame/swollen hocks
What are the lesions associated with Salmonella pullorum
o Peritonitis in chicks that die after hatching
Unabsorbed yolk sac/congested lungs/dark swollen liver
o Typhlitis with cecal casts and necrotic foci in chicks that die after showing disease
What type of poultry does Salmonella gallinarum target
- Target: all birds (clinical disease in growers/adults)
- Rare in commercial production
How is Salmonella gallinarum transmitted
- Transmit: fecal oral (also eggs)
o Food/water
o Caan persist in environment
What are the clinical signs associated with Salmonella gallinarum
- Clinically
o Non specific signs: depression/ruffled feathers/anorexia
What are the lesions associated with Salmonella gallinarum
o Bronzed enlarged liver with necrotic foci
o Kidney and spleen enlargement
o Anemia/enteritis
What is one main consideration for Salmonella gallinarum
Provincially and federally reportable (will cull whole flock)
How is paratyphoid salmonella transmitted
Transmit: transovarian
* Horizontal transmission (in feces – contamaiinate eggshell/enviro)
o Flies/darkling beetle/rodent
Transmit: transovarian
* Horizontal transmission (in feces – contamaiinate eggshell/enviro)
o Flies/darkling beetle/rodent
What is the clinical manifestation of paratyphoid salmonella
Clinically: enteritis
What are 2 main considerations for paratyphoid salmonella
Zoonotic – food poisoning
Provincially reportable
What poultry type is mainly affected by paratyphoid salmonella
Young birds (<2 weeks)
How is salmonella transmitted at different stages of production
Import of contaminated material (bird/fomite)
Within breeding flock = transovarian transmission and horizontal spread between layers
Hatchery: fomites/transovarian/horizontal spread
Processing: carcass contamination/wild bird contamination
How is salmonella diagnosed and what samples are taken
o Diagnose
Sample:
* Tissue: spleen/liver/heart/yolk sac/synovial fluid/brain
* Fluff/litter/dust/feed
Test: C/S and serotyping
List 3 differentials for salmonella
Colibacillosis = septicemia
Newcastle disease = neuro signs
Mycoplasma synoviae = joint
How is salmonella prevented
Live vaccine = S. typhimurium (cross protect to enteritidis)
Killed vaccine = S. enteritidis/Heidelberg/typhimurium
Reduce shedding and transmission
All salmonella serovars are at minimum notifiable
What causes necrotic enteritis? What is the gram type and shape? What are other notable features of the bacteria
- Clostridium perfringens - Necrotic enteritis
o Gram (+) bacilli, form spores and exotoxins (alpha/beta) – anaerobic
o Acute/chronic enterotoxemia
o Economically important
How is C. perfingens transmitted and what are the risk factors
o Transmit: fecal-oral
o Risk
Stress
High energy/protein diets (fish meal/wheat/rye/barley)
Contaminated feed/water mucosal damage (coccidiosis/salmonellosis)
What are the clinical signs of necrotic enteritis
o Clinically
Non specific: depression/ruffled feathers/anorexia/d+
Sudden death in good condition due to enterotoxemia
What are the lesions associated with necrotic enteritis
o Lesions
Fibrinonecrotic enteritis with diphtheritic membranes
Rapid autolysis of dead birds
Turkish towel appearance of small intestinal mucosa
How is necrotic enteritis diagnosed and what samples are taken
Sample:
* Intestinal contents/mucosal scraping/hemorrhagic lymphoid nodules
* Swab of pseudomembranous
Test: anaerobic culture and PCR for toxin typing
What are the differentials for necrotic enteritis
Ulcerative enteritis/Clostridium colinum
Coccidiosis
What are the causative agents of gangrenous dermatitis
- Gangrenous dermatitis
o Agent:
C. perfringens type A
C. septicum
S. aureus
What type of poultry are commonly affected by gangrenous dermatitis? What are the risk factors
o Target: chicken (4-5 wk) and turkey (13-16wk)
Economic impact (condemnation) and sudden increase in mortality
o Risk
Skin lesions
Immunosuppression (density/management)
Contamination (vaccine)
What is the pathogenesis of gangrenous dermatitis
o Pathogenesis (2 ways)
Skin trauma to seed bacteria
intestinal overgrowth resulting in loss of integrity = systemic distribution
toxin production leads to tissue necrosis
What are the clinical signs of gangrenous dermatitis
Depression/anorexia/weak/ataxic/lateral recumbent
What are the lesions associated with gangrenous dermatitis
Skin: areas of no feathers/edema/emphysema/multifocal to coalescing hemorrhage
SC: serosanguinous fluid +/- emphysema
Dead birds autolyze fast
How is gangrenous dermatitis diagnosed? What samples to take?
o Diagnose
Sample
* Swab – exudate
* Tissue – skin with SC/underlying muscle
Test: C/S andd aerobic and anaerobic culture
What are 3 differentials for gangrenous dermatitis
o DDX:
Mycotic dermatitis
Noon-clostridial bacterial cellulitis
Ulcerative dermatitis
What is the disease caused by Bordatella avium? What are the gram types and shape?
- Bordatella avium
o Turkey coryza aka bordatellosis aka turkey rhinotracheitis
o Gram (-) rod – obligate aerobe
What is the main poultry types affected by Bordatella avium? What is its impact?
o Contagious in young poultry with high morbidity (less mortality if not complicated by secondary infection)
If secondary to colibacillosis = devastating
o Opportunistic in broilers
What are the clinical signs of Bordatella avium
Acute sneezing
Catarrhal serous nasal discharge
Watery eyes
Submaxillary edema
Dyspnea
Mortality due to suffocation
What is the pathogenesis of Bordatella avium
o Pathogenesis
colonize ciliated resp epithelium
Proliferation
Osteotoxin/tracheal toxin = damage epithelium and underlying cartilage
How is Bordatella avium diagnosed and what samples are used
o Diagnose
Swab anterior trachea
Test: C/S and serology
List 6 differentials of Bordatella avium
Mycoplasmosis
Chlamydiosis
Ornithobacterium rhinotrracheale
Newcasle disease
AI
Turkey rhinotracheitis/pneumovirus
What disease is caused by Mycoplasma gallisepticum?
- Mycoplasma gallisepticum
o Infectious siniusitis
o Slow onset resp infection – cause severe sinusitis in turkeys
o Rare in commercial production
How is Mycoplasma gallisepticum transmitted
o Transmit: transovarian/direct contact
Recovered birds stay infected and stress can cause recurrraance
Concurrrant infection can worsen disease
Low morbidity and mortality
What are the clinical signs of Mycoplasma gallisepticum
o Cliinically
Nasal/ocular discharge
Cough/rales/poor growth
Swollen sinuses
What are the lesions of Mycoplasma gallisepticum
Swollen sinuses with caseus exudate
Air sacculitis
Pericarditis/hepatitis
How is Mycoplasma gallisepticum diagnosed and what samples
o Diagnose
Sample: swab of trachea/choanal cleft (with special mycoplasma transport media)
Tissue – air sacs/lung/heart/liver
Test: PCR/serology
What are 5 differentials for Mycoplasma gallisepticum
Newcastle disease
Infectious bronchitis virus
Fowl cholera
Infectious coryza
Chlamydiosis
What type of poultry is Mycoplasma more common in? List 3 types and their clinical consequencee
o Mycoplasmosis – more common in small flocks
M. synoviae = joint inflame and resp disease
M. meleagridis = turkey air sacculitis
M. iowae = turkey low hatchability
What is the gram type and shape of Ornithobacterium rhinotracheale? What type of disease does it cause
- Ornithobacterium rhinotracheale
o Gram (-) rod
o Respiratory disease commonly secondary to other agents
Compare the clinical outcomes of Ornithobacterium rhinotracheale in young vs older birds
Young: mild resp signs and nasal discharge
* Facial edema and swelling of infraorbital sinuses
Older: sudden increase in mortality
* Dyspnea/expectoration of blood stained mucous before death
What are the lesions associated with Ornithobacterium rhinotracheale
o Lesions
Sinusitis with caseous exudate
Lung consolidation with fibrinous exudate
Fibrinoheterophiliic air sacculitis
How is Ornithobacterium rhinotracheale diagnosed and what samples do you take
o Diagnose
Sample – tracheal swab in live bird
* Dead bird = trachea/infraorbital sinuses/lung/air sac
Test: C/S and PCR
What are the 4 differentials forr Ornithobacterium rhinotracheale
o DDX:
Fowl cholera
Colibacillosis
Mycoplasmosis
Chlamydiosis
What disease does P. multocida cause in poultry
- P. multocida
o Fowl cholera
What disease does Avibacterium paragallinarium cause in poultry
- Avibacterium paragallinarium
o Infectious coryza
What disease does Chlamydia psittici cause in poultry
- Chlamydia psittici
o Sinusitis
o Conjunctivitis
How does treatment for bacterial disease differ between broilers and layers
o Antibiotics in meat/broiler
o Layer birds not treated due to withdrawl times
