avian infections - cairo university viral infections of respiratory tract newcastel disease virus...
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Avian infections
Viral infections of respiratory tract
Newcastel disease virus
Avian influenza
Avian infectious bronchitis virus
Avian laryngotracheitis disease virus
Adenoviruses
Avian infectious bronchitis virus
Many strains (differ in antigenic properties and
virulence) - mutations and recombination
Affects young animals from 3 weeks
Maternal antibodies control infection for 3 weeks
Suffocation, cough, sternutation, urate plug, drop
of lay, clinical signs last for 10 – 14 days
Avian infectious bronchitis virus
Horizontal spread
Rapid spread – high concentration of animals
Vertical transmission – not demonstrated
Virus replicates in epithelial a subepithelial cells
of repiratory tract and kidney (nefropathogenic
strains)
Virus persistence and long term shedding
Avian infectious bronchitis virus -
diagnostics
Tracheal swabs – till 14 days in chicken, 7-10 days in older, 2-3 weeks in nefropat. strains
Virus isolation in acute phase of the disease
– CAM (2-3 passages)
– tracheal explantates (ciliostasis in 2-3 days
Variant strains and Ag mutants – sentinel SPF animals
Avian infectious
laryngotracheitis virus
Acute disease of chicken, pheasants (3-9 month)
Respiration problems, bloody mucous secretion
Conjunctivitis - panophtalmitis
Mild - peracute disease
Antigenic uniformity, strains differ in virulence
Impact of environment (iritation of resp.tract, low
temperature, concurrent infections)
Avian infectious
laryngotracheitis virus
Virus latency – in infected and vaccinatedanimals
Rezidual pathogenicity of vaccine strains
Cell immunity – non-transmissible to thenewborns
Avian infectious
laryngotracheitis virus
Samples: 4-6 living animals
trachea, larynx - chilled, not frozen
Diagnostics
I.N. inklusions - trachea
IF test – trachea
Izolation on EE (CAM), IFA identification
Differentiation of vaccine and field strains by REA
Newcastel disease virus
Different pathotypes of the virus
– Velogenic (viscerotropic and neurotropic)
– Mezogenic
– Lentogenic
Serologically unique
Respiratory signs in velogenic and mezogenic
strains
Newcastel disease virus
Velogenic strains – respiratory signs (edema of
the neck, head), diarhea, neurological signs,
bleeding, almost 100% mortality
Newcastel disease virus
Diagnostics
Izolation: embryonated eggs
Detection: hemagglutination, PCR
Samples: lungs, spleen, brain, trachea.
Indirect detection: hemagglutination inhibitiontest (HIT) a virus neutralizing test (VNT)
THE RESPIRATORY TRACT
Rhinitis, sinusitis, tracheitis
Mycoplasma gallisepticum
(CHRD) enrofloxacin p.o. Live vac..-aerosol.
lincomycin p.o.
tilmicosin p.o.
H. paragallinarum amoxicilin p.o.
(hemofilová rýma)
pneumonia
Mycoplasma synoviae linkomycin p.o.
tilmikosin p.o.
Pasteurella multocida amoxicilin p.o. inakt. vak. s.c.
(fowl cholera)
Bordetella avium amoxicilin p.o.
(rhinotracheitis, bordetelosis)
THE RESPIRATORY TRACT
rhinotracheitis ,pneumonia, pleuritis, airsaculitis
O. rhinotracheale amoxicillin p.o. inakt. vak. s.c.
(ornithobacteriosis) doxycyclin p.o.
airsacculitis
E. coli flumequin p.o.
M. synoviae
Mycoplasma meleagridis* lincomycin p.o.
(aerosacculitis in turkey) tilmicosin p.o.
Mycotic infections
A. flavus, A. fumigatus
(aspergilosis)
THE RESPIRATORY TRACTMycotic infections (aspergilosis)
Brooder pneumonia in newly-hatches chickens in incubators
Neumonia and airsacculitis – up to 6 weeks of age
A. flavus, A. fumigatus
Infection of GIT
Newcastel disease virus choroba
Avian influenza
Avian influenza
Different clinical course – inaparentní … drop of
lay… …high mortality
Virulence doesn´t depend on H and N antigens
Edema of the crest, visceral hemorhagies, green
diarhea, urate deposits in kidney, yolk peritonitis
Avian influenza - diagnostics
Izolatio on EE
HA test
Antibody detection by HIT
Differentiation of Newcastel disease virus
THE ALIMENTARY TRACTEnteritis
Clostridium perfringens typ A, C
Clostridium colinum amoxicillin p.o.
(necrotic enteritis)
Salmonella Pullorum flumequin p.o.
(fowl typhoid) enrofloxacin p.o.
Salmonella Gallinarum flumequin p.o. live vac.. i.m.
(fowl typhoid) enrofloxacin p.o.
THE ALIMENTARY TRACTSalmonella. spp.-S. Enteritidis, S. Typhimurium
(paratyphoid infection) enrofloxacin p.o. live-/inact.vac. s.c.
flumechin p.o.
Salmonella Arizonae enrofloxacin p.o.
(arizonosis in turkey) flumequin p.o.
Campylobacter jejuni ´ erythromycin p.o.
(kampylobacteriosis)
E.coli encofloxacin
(coligranulomatosis)
Y. eneterocolitica
THE ALIMENTARY TRACT
peritonitis
E. coli flumequin p.o.
Pasteurella multocida amoxicillin p.o. inact. vac. s.c.,i.m.
enro/difloxacin p.o.
flumequin p.o.
Mycobacterium avium/subsp. avium NO TREATMENT
LIVER
hepatitis
E.coli flumechin p.o. subunit. vac. s.c.
Salmonella spp. enrofloxacin p.o.
(S.Gallinarum, S.Pullorum)
P. multocida amoxicillin p.o.
Campylobacter jejuni
Erysipelothrix rhusiopathiae amoxicillin p.o.
Y. pseudotuberculosis
Perihepatitis
M. gallisepticum
Infection of CNS
Avian encephalomyelitis
Newcastel disease virus
Avian encephalomyelitis virus
Primary replication in the gut
Serologic uniformity, strains differ in virulence
Clinical signs up to 6 weeks after birth
Ataxy, paralysis and tremor
Zákal čočky, iridocyklitis
Drop of lay, transovaral spread
Changes in CNS only, not in meninges orperipheral nerves
Avian encephalomyelitis virus
Clinical signs
Anamnesis – no vaccination
Limited pathologic changes
IFA detection in the brain
Isolation in yolk sac of EE (IFA confirmation)
Serology– VN test non EE – monitoring of vaccination
– ELISA
– ID test
THE REPRODUCTIVE SYSTEM
Mycoplasma spp. tilmicosin p.o.
M.gallisepcticum
M.meleagridis (turkey)
salpingitis
E. coli, flumequin p.o.
Salmonella spp.
egg yolk saculitis and sepsis
E. coli flumecquin p.o.
Pseudomonas aeruginosa enro/difloxacin p.o.
Staphylococcus aureus amoxicillin p.o.
Clostridium perfringens amoxicillin p.o.
Enterococcus spp., amoxicilin p.o.
Enterococcus faecalis
THE MUSCULOSKELETAL SYSTEM
Artritis, sinovitis, tendosynovitis
Staphylococcus aureus amoxicillin p.o.
E. coli flumequin p.o.
Mycoplasma synoviae tilmicosin p.o.
(infekční synovitida kuřatrůt) lincomycin p.o.
Pasteurella multocida potenc.sulfonamides p.o.
(cholera drůbeže) flumequin p.o.
Erysipelothrix rhusiopathiae amoxicillin p.o.
benzylpenicillin i.m.
osteomyelitis
E.coli enrofloxacin p.o.
Staphylococcus aureus lincomycin p.o.
tylosin p.o.
Infection of the lymphatic tissue
Infectious bursitis virus
Avian leukosis
Marek´s disease virus
Chicken anemia virus
Infectious bursitis virus
2 serotypes (chicken -1, duck-typ 2)
6 antigenic subtypes in the type 1, variant strains
Virus is very stable (up to 4 month)
Highly contagious disease
Incubation period 1-3 days
Clinical signs during 24 h. in 100% of animals
Susceptible animals 3 – 12 weeks
Infectious bursitis virus
Virus replication in lymphocytes
Longlasting immunosupression (humoral,
cell-mediated)
100% morbidity, up to 20% mortality
Edema of bursa Fabricii, hemorrhagies in
muscles,
Atrophy of bursa
Infectious bursitis virus
Diagnostics
Isolation on CAM (death of embryo in 3-5 days)
Virus isolation on TC (confirmation by IF)
Antigen capture ELISA
Infectious bursitis virus
Serology – ELISA
Monitoring of antibodies in the flock
Serological profile – estimation of maternalimmunity, vaccine schedulind
Infectious bursitis virus
VN test
Detection of antigennic variants (ELISA is type specific)
Avian leukosis virus
ALV – neoplastic disease of chicken
Groups ABCD (E endogenous), FG pheasants
Reticuloendotheliosis (REV) in turkey, quails, ducks,
in chicken serological detection only
Avian leukosis
Ubiquitous spread
Low clinical incidence
Vertical spread
Horizontal spread
Incubation period –more than 14 weeks
Lymphoma of B cells in bursa Fabricii, metastasis
in liver and spleen
Clinical signs – nonspecific
Avian leukosis
Diagnostics
Detection of LL nodules in BF (from 16 weeks) is
pathognomic
IF detection of IgM Ag and B-cell markers
Avian leukosis
Dg. tests
COFAL test
ELISA-ALV
Biological assay
gs antigens
Marek´s disease virus
Lymphoproliferative disease in chickens
Serotype 1 patogenic and oncogenic strains
Serotype 2 avirulent and nononcogenic strains
Serotype 3 avirulent, in turkey only (vaccinestrains)
Marek´s disease virus
Clinical signs from 6 – 16 weeks
Majority of neoplastic changes in broilers
Mononuclear (lymphoblasts) infiltration in peripheral nerves and other organs
Lymphomas in gonads, hearth, lungs, seldom in BF, skin, muscles
Ataxy, paralysis, macroscopic thickening ofperipheral nerves
Marek´s disease virus
Neurolymphomatosis – klasical MD, loss ofcoordination, asymetric paresis and paralysis
Acute MD – expanzive burst in the flock, depression, ataxy, paralysis in some animals. Significant mortality without neurolog. changes
Lymphomatosis of the eye – lymphoblastoidinfiltration of pupil, blindness
Skin form – round, nodular lesions in featherfolicles
Marek´s disease virus
K inf. dochází respiratorní cestou, brzy následuje lytická infekce B buněk ve slezině a thymu
Následující zánětlivé změny vedou k infiltraci monocyty, makrofágy, granulocyty a lymfocyty
Klidové T buňky jsou rezistentní k infekci, u aktivovaných dochází k lytické infekci –imunosuprese nebo transformaci – tumory
K produktivní infekci dochází pouze v buňkách péřových folikulů!
Místem latence jsou T lymfocyty
Marek´s disease virus
Diagnostics
The detection of the virus or antibodies isnot significant
MATSA antigens
Chicken anemia virus
Disease of chickens in 2-3 weeks
– Transovarial infection
– Horizontal spread after birth
Aplazia of bone marrow (erys., tromb., granulocyty)
Thymus atrophy (patognomic)
Anorexia, fever, pallor
Chicken anemia virus
Clinical signs
Biological assay (i.p. aplication)
Cell line MDCC-MSB1 (then IFA)
PCR
Colisepsis
– E.coli
Fowl typhoid
– S. Gallinarum
Septicemia
– P.multocida (fowl cholera)
– S.aureus
– S. equi subsp. zooepidemicus
– E.rhusiopathie
Mycoses
Generalized aspergilosis– A. flavus, A.fumigatus
SYSTEMIC INFECTIONS.
THE EYEConjunctivitis
–M. gallisepticum