Avian diseases

Things that are difficult or might be tested on for the exam

Which gram negative, non-spore forming bacillus bacteria has zoonotic potential?

Escherichia coli

• Shiga toxin producing EC

• E.coli O157: H7

What media culture is used for E.coli

MAC-bright pink

EMB- metallic green

State the types of transmission for E.coli

• Horizontal: fecal-oral (present in intestine) via contaminated feed, water, rodent droppings, wild birds, mechanical vectors (darkling beetles, flies)

• Vertical: transmitted via the infected ovary, oviduct, or eggshell contamination.

State the predisposing factors for E.coli infection

• Breeder level: fecal contamination on eggs in nest box, hens with salpingitis

• Hatchery level: poor air quality, poor sanitation (setters, trays), in-ovo vaccination contamination

• Farm level: poor sanitation, poor ventilation, overcrowding, poor litter management

Predisposing viruses for E.coli

• CAV, NDV, Metapneumovirus, IBV

Predisposing bacteria for E.coli

• MG, MS, Pasteurella multocida, Coryza

What bacteria cause swollen head?

• E. coli

• Avian metapneumovirus

• Infectious Bronchitis

State the clinical signs of E.coli

• Snicking, swollen heads, labored breathing, recumbent birds

State the condition and the disease that causes it.

Omphalitis caused by E.coli , Salmonella, Enterococcus, Pseudomonas

State the condition and etiological disease

• Polyserositis caused by E.coli

• Pericarditis- E.coli, Chlamydophila, Pasteurella, Streptococcus, Enterococcus

• Perihepatitis

• Airsacculitis- Mycoplasmas, Chlamydophila, Pasteurella, IBV, Infectious Coryza, NH3

State the condition and etiological disease

Salpingitis and peritonitis caused by E.coli

State the condition and the etiological disease

Synovitis and Osteoarthritis caused by E.coli, Reovirus, Staphylococcus, Enterococcus, Mycoplasma

What bacteria is bacillus, negative, non spore forming, non motile and facultative aerobic?

Pasteurella multocida- Fowl Cholera

Source of infection for Fowl Cholera?

Rodents, swine, cats, humans, wild birds, insects

State the transmission for Pasteurella multocida

• Horizontal: water contaminated by oral fluids, cannibalism of dead birds, respiratory route, fomites.

Three forms of clinical signs for pasteurella multocida

• Peracute: sudden mortality

• Acute: ruffled feathers, anorexia, mucous discharge, diarrhea, increase respiratory rate

• Chronic: weight loss, death, swollen (wattles, sinuses, footpad, tendon sheaths)

• Cardiac tamponade in turkey

What disease causes swollen wattles?

• Fowl cholera

What is the pathogenesis for Chicken Infectious Anemia?

• Loss of haematopoietic cells and replaced with adipose tissue in bone marrow

• Impaired cellular immunity by infecting T lymphocyte precursors

• Virus attack on mature antigen specific T cells dividing

The main target cells for CAV?

• Hemocytoblasts in the bone marrow

• T cell progenitors in the cortex of the thymus

Types of transmission for CAV?

• Horizontal: fecal-oral route

• Vertical: from infected hens

What disease cause this condition?

Blue wing syndrome caused by CAV in chicks 1-4wks old

State the disease causing these lesions, and state the lesions as well.

• Thymus atrophy, adipose tissue in bone marrow, haemorrhages in muscle and proventricular mucosa, enlarged mottled liver caused by CAV

What are the two serotypes of Gumboro disease and which is prevalent in what species?

Infectious Bursal disease virus 

• S1: pathogenic in chickens

• S2: nonpathogenic in chickens but has Ab in turkeys, ducks, chickens

Why are birds affected 3-6 weeks by IBDV and state the transmission.

• Wane off of maternal Ab

• Horizontal via fecal-oral, direct contact, inhalation, feed and water

IBDV attacks what?

B lymphocytes of the Bursa of Fabricius 

What disease causes whitish watery diarrhea?

• IBDV

State the gross lesions associated with Gumboro

• Vent picking leading to anus prolapse, bursal edema, bursal atrophy, lymphocytic necrosis, hemorrhages on muscle, necrotic exudate on lumen

What is being assessed here?

Bursal scoring for IBDV

What does Marek disease cause?

Neoplastia, nerve damage, B-cell lysis, and T-cell transformation in chickens, turkey, and quail

Three serotypes of Marek

• S1: oncogenic to chickens

• S2 and 3: non-oncogenic

Transmission for Marek disease

• Horizontal: inhalation of feather follicular dander

• Asymptomatic carriers

• Environmental contamination

How long does it take for vaccination immunity to be effective in birds?

7-10 days

State the four phases of infection for Mareks

• Early productive-restrictive phase: inhale dander cause resp and macrophage infection, viremia, cytolytic infection of B & T cells → immunosuppression

• Latent phase: development in T cell clashing with CMI response

• Feather follicle shedding: Infected lymphocytes transfer FFE 

• Proliferative/lymphoproliferative disease: viremia 2 weeks pi

What disease causes torticollis and paralysis of wings and legs?

Marek disease

What disease causes blindness?

Mareks

What disease causes the nerve enlargement (sciatic, vagus, brachial), feather follicle enlargement, and tumors on visceral organs?

Marek

What can be done to prevent Marek?

• Rispen (S1) vaccine

Peracute, acute and chronic forms of Fowl Cholera

• Peracute: death no lesions

• Acute: Pneumonia, splenohepatomegaly, yolk peritonitis

• Chronic: Arthritis, tendonitis, osteoarthritis, conjunctivitis, sinusitis 

What disease causes mottled (speckled) liver and spleen

• Fowl Cholera

State the species for each Mycoplasma disease

• M. gallisepticum: Chicken and turkey pathogenic

• M. synoviae: Chickens and turkey (resp form > synovial form)

• M. meleagridis: Turkeys (Resp, repro, skeletal form)

• M. iowae: Turkeys

What conditions does each disease of Mycoplasma cause?

MG: CRD (chicken) and Infectious sinusitis (turkey)

MS: Infectious synovitis (chicken and turkey)

MM,MS, MG in NPIP

Which disease causes a 'fried egg' appearance in which medium?

Mycoplasma in eaton agar, frey medium, mycoplasma specific serum

Can M. gallisepticum survive in the environment?

No, it needs a carrier that doesn’t cause disease unless they are stressed or immunosuppressed.

State the transmission for MG.

• Vertical: transovarial

• Horizontal: humans, feathers, exudate, fomites, mechanical vectors

What diseases, environmental stressors and social stressors can cause MG?

• Disease: IBDV, NDV, E.coli

• Environment: poor ventilation, sanitation, ammonia, temperature, humidity

• Social: toms fighting

What diseases cause swelling of the infraorbital sinuses, nasal discharge, and conjunctivitis in turkeys?

Mycoplasma

Bordetella avium

Clinical signs associated with Mycoplasma in chickens

Snicking, labored breathing, ocular and nasal discharge (watery-mucoid)

State the lesions associated with Mycoplasma infections

• Exudate in air sac resembling soap and suds

• Mucoid to catarrhal exudate in nasal passage, trachea, bronchi, and thoracic. 

State some DDx for Mycoplasma in chickens and turkey

• Chicken: NDV, AI, E.coli, Fowl Cholera

• Turkey: E. coli, NDV, ORT, Fowl Cholera

What disease causes joint swelling and eggshell apex abnormality?

M. synoviae 

Apart from joint issues caused by M. synoviae, what conditions above does it also cause?

Respiratory form: Tracheitis, sinusitis, airsacculitis

Avian leukosis cause

Neoplasia of Bursa and metastasis on nearby tissues

Transmission for Avian Leukosis

• Vertical: Transovarially

• Horizontal: fecal-oral, equipment, sexing

Which form of Avian leukosis virus cause issues in broilers?

ALV-J

Which disease causes big liver disease (tumors) and tumors on the bursa, spleen, bones, and haemangiomas?

Avian Leukosis

State the treatment and prevention for ALV

• No treatment, only eradicate

State the type of bursal tumor in mareks, ALV, and Reticuloendotheliosis.

• Marek: interfollicular

• ALV and Reticulo: Intrafollicular 

Tumors in the brain and eye is associated with which viral disease?

Mareks

Viral arthritis involves?

• Rupture of digital flexor and gastrocnemius tendon

• Tenosinovitis (tarsus and metatarsus)

Host and syndromes for Reovirus

• Chickens: Malabsorption Syndrome, Runting/Stunting Syndrome, Enteric disease, Immunosuppression, Respiratory & Neurological issues

• Turkeys: Enteritis (PEMS)

Transmission for Reovirus

• Vertical: eggs of breeder flock

• Horizontal: fecal-oral, aerosol, infected chicks at hatchery

What disease causes discolouration, swelling of the tendon sheath, and a lack of symmetrical size in birds and lameness?

Reovirus/ Viral arthritis

Another name for fowl plague and is it zoonotic?

Avian influenza is zoonotic

Which type of influenza affects birds?

Avian influenza A

Source of infection for Avian influenza

Waterfowl and shorebirds are asymptomatic and excrete virus, swine, water sources

Transmission for Avian influenza

Horizontal only; fomites, direct contact, droppings

Clinical signs in LPAI and HPAI

• LPAI: Airsacculitis, rhinitis, tracheitis, sinusitis 

• HPAI: death, torticollis, necrosis, cyanosis of comb and wattles

What disease causes this cyanosis/hemorrhages of wattles, comb anad feet?

HPAI

DDx for HPAI and LPAI

• HPAI: NDV, Fowl cholera, heat, water deprivation

• LPAI: Metapneumovirus, mycoplasma, chlamydia 

Name for Avibacterium paragallinarum and is it zoonotic?

Infectious Coryza is not zoonotic

What does Coryza require for culture on which agar?

Nicotinamide adenine dinucleotide (V factor) with Staph. on chocolate or blood agar 

Transmission for A. paragallinarum

• Horizontal: direct contact, aerosol, water, feed

What diseases cause facial edema with nasal and ocular discharge?

Infectious coryza, E.coli, Pasteurella, IBV

What disease causes acute catarrhal inflammation of the sinuses and nasal passages?

Infectious coryza

Ddx of infectious coryza

fowl cholera, fowl pox, IBV, E.coli

Which genotype of avian chlamydiosis is prevalent in psittacines and state if it is zoonotic.

Genotype A and all genotypes are zoonotic

Transmission for chlamydia 

• Horizontal only; inhalation and ingestion of feces

Clinical signs of Chlamydia

• Ruffled feathers, nasal discharge, yellow green diarrhea, neurological issues, conjunctivitis

Diagnosis of Chlamydia

Giemsa and PVK stain

PCR of liver and spleen

DDx of chlamydia

MG, Influenza, E.coli, fowl cholera

How to treat pet birds with chlamydia psittaci?

Doxycycline in water for 45 days, no vaccines available

Name each Clostridium spp in avian

• C. botulinum (limber neck)- duck

• C. septicum (gangrenous dermatitis)- chickens

• C. perfringens (necrotic enteritis)- chickens, ratites, psittacines

• C. colinum (ulcerative enteritis)- quail

Which toxin is associated with C. perfringens?

Toxinotype G: alpha, Net B toxin

Predisposing factors for C. perfringens

high protein, high cereal grain, animal fat, intestinal parasites, litter moisture

What disease cause distended and friable intestines?

C. perfringens (necrotic enteritis)

What disease causes the Turkish towel appearance on the intestines?

Clostridium perfringens

Diagnosis for Clostridium perfringens

anaerobic culture, PCR, immunohistochemistry

What disease causes wing rot, dermatomyositis, gas edema, bubbly tail, and blue wing?

C. septicum (gangrenous dermatitis)

Predisposing factors for C. septicum

scratches, wounds, overcrowding, inadequate Na cause fighting and pecking, lysine and methionine deficiency cause cannibalism 

What disease causes green-black patches on skin, feather loss, and muscle hemorrhage?

Clostridium septicum

DDx of C. septicum

Breast burn from ammonia, HPAI, NDV

Toxin associated with C. botulinum

Type C

What disease causes neck, wing, leg, and eyelid paralysis in waterfowl?

C. botulinum 

Transmission of C. botulinum

• Horizontal: ingestion of preformed neurotoxin of C. botulinum in lakes with dead carcasses, vegetation, larvae, feed

Diagnosis of C. botulism

Mouse bioassay test

What disease causes ulcerations, hemorrhages on the duodenum, and yellow liver mottling?

C. colinum

Newcastle disease causes

APMV-1 causes an acute and contagious virus in all avian species with respiratory, enteritis, and neuro issues

Is Newcastle zoonotic and if so, what is the treatment?

Yes but self limiting conjunctivitis with flu symptoms

Pathotypes of Newcastle

• Asymptomatic

• Lentogenic

• Mesogenic

• Velogenic

  • Viscerotropic: hemorrhage intestinal lesions

  • Neurotropic: respiratory and neurological signs

Transmission of Newcastle disease

• Horizontal: secretions and excretions from wild birds/waterfowl

• Vertical: eggs laid by infected hens