Poultry pathology 6. Flashcards
Derzsy’s disease
pathogen
- goose parvovirus GPV (ssDNA)
- geese and muscovy duck
- orofecal infection
- widespread, very resistant • viraemia
goose plague goose viral enteritis goose infectious myocarditis goose hepatitise goose infectious ascites goose hepato -nephritis goose infuenza
Derzsy’s disease
pathogenesis
• per os infection, multiplication in the
whole GI tract
-small intestine, Lieberkühn-glands, crypt cell nucleus
• primer virusenteritis
-acute catarrhal inflammation
-pseudomembrane
-necrosis
• viraemia
• infection of all organs- young parenchyma cell nucleus
• the viraemia results in endothelial damage
-blood plasma leaks to the tissues and cavities=> ascites
• the heart muscle is also affected
-multiplication in the nuclei
-myocardosis, necrosis
-reactive myocarditis
Derzsy’s disease
statistics
chance of infection in intensive producing areas
(CHN, ET, PL, HU, FR, UK): 100%
• morbidity 100% - until the end of the 4th week of life
• mortality 30-40 % if unprotected
• with adequate immunity: 3-5%
• infection after 4 weeks: asymptomatic carrier
• adult bird:
-inapparent infection
-asymptomatic shedding
• chronic form: feather development disorder
• immunosupression
Derzsy’s disease in ducks
• short beak and dwarfism syndrome (SBDS) in
the Moscovy duck
(Cairina moschata)
mallard & house duck (Anas platyrhynchos)
Pekin duck is a breed
mulard or moulard duck:
hybrid of the two domesticated species
Hemorrhagic nephritis enteritis of geese (HNEG)
Goose hemorrhagic polyomavirus (GHPV) • edema in the subcutaneous tissue • ascites, jelly-like abdomial fluid • nephritis > gout/uricosis • rarely haemorrhagic enteritis
Infectious chicken nephritis
Pathogen
- Avian nephritis virus (ANV)
- chicken and turkey
- any age
- mostly young, 1-3. week
- orofecal infection
- severity is age dependent
- embryo mortality
- day-old – clinical disease
- older birds – production loss
- clinical disease is rare
- subclinical disease and production loss is common
Infectious chicken nephritis
Pathogenesis
• jejunum enterocyte • malsecretio, maldigestio, malabsorptio • viraemia • multi-organ multiplocation • most damage in the kidneys • tubular epithelial cells • necrosis (tubulonephrosis) • reactive interstitial inflammation =>gout/uricosis
Infectious chicken nephritis
Economic impact
• chick quality/omphalitis?
• survivors suffer serious growth retardatrion
=>RSS/PEMS (runting-stunting, poult enteritis malabsorption)
• uneven flock, shifting feed conversion = economic catastrophe
• or you keep them longer > the chicken price will not cover the feeding
cost
• or you sell them as second-third class product > the chicken price will not
cover the feeding cost
(200 000 chicken eats around 250k €, the profit is 16k € if no problem)
Turkey viral hepatitis (TVH)
- Picornavirus
- USA, CDN, EU
- young poult (<5 hét)
- 100% morbidity
- 25% mortality
- hepatitis and pancreatitis
- catarrhal enteritis
Duck Hepatitis Virus
- DHV-1 = duck hepatitis A virus DHAV-1,2,3
- 1949, Long Island, USA
- Picornavirus - Avihepatovirus
- DHV-2 = DAstV-1
- 1965, Norfolk, UK, since then only in China
- Astrovirus
- DHV-3 = DAstV-2
- 1969 Long Island, USA, nowhere else
- Astrovirus
Duck hepatitis
Patho
- Young (1-6 week) ducks
- acute, highly infectious, quick and high mortality
Pathologic forms
-peracute: haemorrhagic liver dystrophia , inclusion bodies in the cytoplasm
-acute: serous hepatitis • yellow colour • structure faded, necrobiosis
• necrosis
• infiltration with inflammatory cells
-subacute-chronic: cholangiolitis
• biliary proliferation
• catarrhal enteritis
• kidney, spleen, heart muscle degeneration, inflammation
Avian hepatitis-E
- big liver and spleen disease BLS (AUS, 1980)
- hepatitis-splenomegalia (CDN, 1991)
- Hepeviridae (ssRNA+)
- avian hepatitis-E virus
- hepatitis and viraemia
- chicken
- ”above normal mortality” (weekly 0,3-1%)
- significant production loss (5-10-20%)
- anorexia, lethargy, anaemia, feather malformation
Avian hepatitis-E-virus
pathology
acute form • haemorrhages (liver, spleen, pancreas) • ascites (yellow or red) • serous hepatitis -swollen -pale or yellow -friable • splenomegaly
subacute form • liver dystrophy • subcapsular haemorrhages and pale foci • internal bleeding • splenomegaly (>1g/bw kg) -haemorrhages and pale foci • pancreatic haemorrhages and pale foci • degeneration of the ovaries, rupture of follicles • consequential (irritative) peritonitis
Arbovirus infections
• "arthropod- borne-virus" • tick, fly, mosquitoes, Culicoides • Togaviridae, Flaviviridae, Bunyaviridae • generally tropical diseases • WNv is spreading in Europe • Differentiation of CNS symptoms • AI, AMPV, AE
Transmissible viral proventriculitis (TVP)
• chicken proventricular necrosis virus (CPNV) -Birnaviridae, Avibirnavirus • young (broiler) chicken • rarely hens • inflammation and dilatation of the proventriculus -thick wall -lymphocytic infiltration • severe maldigestion • ruptures at slaughter contamination & condemnation
