Infectious diseases in exotic birds I. Winter term 2010
Preventive measure 1) Isolation of susceptible or naive animals 2) Diagnostic testing followed isolation or removal of test-positive animals 3) Genetic selection of disease-resistant population of animals 4) Vaccination to prevent disease and restrict an organism´s amplification within a host or population of hosts.
Important infectious disease • Psittacine circovirus formerly psittacine beak and feather disease virus (BFDV) • Avian Polyomavirus • Herpesvirus infection • Poxvirus • Chlamydophilla • Megabacteriosis
Viral disease of skin psittacine beak and feather disease psittacine circovirus – BFDV
avian polyomavirus cutaneous form of pox
Immunosupresion in chicken infection with BFDV infection with pigeon circovirus Infection with APV
Papillomatosis
Papillomavirus napĹ™. PePV
Herpesvirus
Hepatitis Pacheco disease (PsHV or PDV) Chlamydophilosis Adenovirus infection of parrot Infection with APV Infection with BFDV
Neural sings of viral origin Psittacine proventricular dilatation (PPD) –stage of affection of CNS Infection with paramyxovirus PMV-3
Infection with Pacheco Infection with WNV – West Nile virus
Infection with Paramyxo PMV-3 • Paramyxovirus type 3 is presently the most common paramyxovirus in psittacines (Neophema spp. and other parakeets) and passerines (finches) and it can lead to severe illness in these birds. • The disease is characterized by acute or chronic pancreatitis and central nervous symptoms,such as torticollis as well as walking in circles. and by high mortality rates in the affected flocks
Steatorrhea
Clinically important viral disease Important viral disease of Psittaciformes • •
Psittacine circovirus Avian polyomavirus
• Pacheco disease • Poxvirus • Papillomatosis
Clinically important viral disease Important viral disease of Columbiformes • Paramyxoviral infection (PPMV-1) • Avian poxvirus (Pox virus) • Pigeon herpesvirus (PHV-1) • Pigeon circovirus (PiCV) • Pigeon adenovirus
Clinically important viral disease Important viral disease of Passeriformes • Canary poxvirus • Paramyxovirus infection (PMV-3) • Finch polyomavirus (FPyV ) • Fringilla papillomavirus (FPV) • Circovirus of starlings (SCV)
Diagnostics • History and clinical sings • Postmortem finding + histology • Serological investigation • Virological investigation – Electron microskopy – cultivation (poxvirus) – polymerase chain reaction (PCR, RT-PCR)
Circoviral infection Synonymum • nemoc zobáku a peří papoušků • Psittacine Beak and Feather Disease (PBFD) Characteristic • disorder of plumage • degenerative change of the beak • immunosupresion
Circoviral infection Susceptible species • majority of species of parrot (all?) • frequently cockatoo, african grey parrots (AGP) • budgerigar a eclectus
Circoviral infection Etiology • psittacine circovirus (BFDV) • smallest virus (14-17 nm) • noneveloped → resistent to desinfection • circular ss-DNA • without propagation in vitro • naturally ocurence in Australia • disease of 1-year old cockatoo
Circoviral infection Clinical sings •
course of disease depend on species and age of birds
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acute x chronical
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acute mainly in chicken to 6 month of age
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chronical in older, frequently to 3 years
Circoviral infection Acute course •
chicken and fledgling of cockatoo and AGP to 6 month of age
•depresion, regurgition
•quickly developement of change on the plumage on the whole body • often peracute course and perishing without sings
Circoviral infection Acute course • severe leukocytopenia → immunosupression
• death loss mainly to 6 month of age, often as results of secondary infection
• without changes on the beak
Circoviral infection Disorder of plumage • decrease amount of feather powder → horn of beak is without shine • feather is falling out
• dysplasia of feathers • dystrofic line in the feathers
Circoviral infection Disorder of plumage •
dystrofic line in the feathers
Circoviral infection Disorder of plumage •
hemorrhage within the pulp cavity
• retention of feather sheaths
Circumferential constrictions.→ fractures of the feather shaft→ hemorrhage
Circoviral infection Acute infection in AGP •
disorder of plumage lika in cockatoo
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extra progresive, nonregenerative anemia
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red discoloratio of grey feathers ← disorder of liver
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often sudden death without sings as results of secundary infection
Circoviral infection Acute infection in AGP • postmortem or on X-ray hepatomegalia • histological necrotic lesion in the liver
Circoviral infection Chronic infection • often in adult in age between 6 months to 3 years • typical for cockatoo, but occur in other species • initially lack of feather powder • molting is prolonged • dysplastic feathers (contour and powder), first sporadically, only in some feather tracts, progressively dispersedly on the body
Circoviral infection Chronic infection • can finish complete baldness
Circoviral infection Chronic infection • deformation of plumage is identical as in acute curse Degenerative alteration of beak • typical for cockatoo, others rarely • in late stage of disease • poor quality of horn • overgrowing, fissure, fracturs • necrosis of palate mucousa → pain → anorexia
Circoviral infection Chronic infection • course of infection is progressive • prognosis in most cases is bad • death in to 6-12 months past detection of sings • often death on the secundary infection (bacterial, fungal) or on the starvation due to pain of beak • South American parrots are less susceptible, possibility of recovery
Circoviral infection Lovebirds, eklectus •
infection is common
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change of plumage are not so frequent
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infection is to fatal
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predominantly become ill young adult birds
Circoviral infection Budgerigar • infection is not so common • change of plumage is others as in cockatoo • affected mainly wings and tails feathers → runners • clinically identically with polymavirus infection – together with APV infection component of syndroms „French moult “
Circoviral infection Transmission •
affected birds spread virus in feaces and in feather powder → inhalational infection
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vertical transmission
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virus too in contents of crop → transmission during naturaly breeding of chicken in the nest
Incubation period •
minimally 3 week to months up to years
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often subclinical infection with spreading of virus
Circoviral infection Replication of virus •
in germinative epitel of follicles → change of plumage
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in germinative epitel of beak → degeneration of beak
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in bursa Fabricous (BF), thymus → immunossupresion
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and other tissue
Circoviral infection Diagnostical method • clinical sings • HMT – leukocytopenia, relative lymfocytosis, anemia • BCH – AST, LDH, bille acid in serum, ↓TP • RTG – hepatomegalia • Post mortem – atrophy of BF, hepatomegalia
Circoviral infection Confirmation of diagnosis • Change of plumage → histology of feather folicle and feathers – intracelular and intranuclear inclusion body
Circoviral infection Confirmation of diagnosis • sampling of blood, feaces, feathers or tisues for PCR (contamination !) • better pair sampling for PCR after 30-90 days • electron microscopy →require great mount of virus • ideal combination histology + PCR or EM
Circoviral infection Therapy • any specifical antiviral therapy • attempt of good body codition – nutrition, vitamins • secundary infection – zoohygiene, ATB,antimycotics • imunostimulation – β-glukany, vitamins
Circoviral infection Precaution •
not breed together small and large species of parrots
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after purchase or after exibition 30-90 days of quarantine
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in quarantine make pair investigation by using PCR
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positive bird put in the quarantine
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aviary is closed for public
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before entry thorough hygiene
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virus is highly resistant agains common desifection agens
Polyomavirus infection Synonyms •
Budgerigar fledgling disease (BFD)
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French moult (together with BFDV)
Characteristic •
change of plumage
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death of young birds or chickens
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failure of coagulability of blood → haemorrhage
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course depend on the age and species
Polyomavirus infection Etiology • avian polyomavirus •
40-48 nm
• non enveloped • → resistant again desinfection • circular ds-DNA
Polyomavirus infection • possibility of infection of all birds species (parrots, songbird, birds of prey, gulls etc.)
Polyomavirus infection Clinical sings • course depended of the species and age of infected individual Budgerigar • acute course • high mortality of chicken to 10.-20. day of age • chronical course • change of plumage in elderly birds (fledgling)
Polyomavirus infection Acute illness of budgerigars • in chicken to 10.-20. days of age
• death of chicken in good body condition
• without apparent clinical sings
• haemorrhage in subcutis
Polyomavirus infection Chronical illness of budgerigars • change of plumage in eldery birds and in fledgling • clinically identical to BFDV infection • after molting normal plumage
Polyomavirus infection Change of plumage
Polyomavirus infection Others parrots (mainly macaws, conures) • sudden deaths in hand rearing chicken between 2.-12. week of age • without sings or death to 24 hours past occurence • weakness, paleness, inapetence, dehydratation, subcutaneous hemorhagy, crop stasis • change of plumage seldom
Polyomavirus infection Lovebirds • nonspecifical illness, possibly death of young adult birds
Songbirds • sudden death of chicken and young adult birds • not very frequent
Polyomavirus infection Transmission •
spreading in feather powder, feaces and oral secretions
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widely spreading in chicken and in birds to 6 monts of age → spreading and maintenance infection in aviary
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post puberty is spreading decreased
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infection via inhalation
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vertical transmission
Polyomavirus infection Incubation period • in budgerigars short – some days • in others about 2 weeks • in majority of adults budgerigars subclinically infection • in others species birds subclinically infection in majority of chickens
Polyomavirus infection Diagnostic • history • clinical sings Postmortem findings • Haemorhage on the pericard, proventriculus et. • Necrotic focus in the liver • hyperemic, swolen kidney • dilatation of heart
Polyomavirus infection Diagnostic
Histology • miliary to confluent necrosis of liver • glomerulonefropaty from immunocomplexs • bazofil intranuklear inclusion body PCR • sampling of blood, feaces, feathers, skin or organs • pair sampling after 30 days
Polyomavirus infection Precaution •
any specifical antiviral therapy
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in budgerigards help stop of breeding minimally to 7 months
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mechanically cleaning + desinfection
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leave only eldery birds
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virus is resistant to many desinfection agens
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effective – chemical compound of chlorine, ethanol
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support of immunity
Polyomavirus infection Precaution • not breed together small and large species of parrots • quarantine + repeated investigation by PCR in new birds and birds returned from exibitions • vaccination (in US) - predominantly in large parrots
Pacheco disease Transmission •
spreading in feces and secrets
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Infection via inhalation and direct contact
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source of infection are latently infected individuals
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vectors primarily some species of conures – resistant to clinical disease
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trigger of disease is stress
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often after transport
Pacheco disease Acute course •
nonspecific sings – apathy, anorexia, ruffled feathers, intermittent diarrhea, PU/PD
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loose feaces with yellow color and urates (necrosis of liver)
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occasionally sinusitis, haemorragical diarrhea, conjunctivitis, spasm, tremor
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death of high percentage birds in aviary
Peracute course •
death without sings
Pacheco disease Post mortem findings • swollen yellow-brown, pale red or greenish liver with subseros haemorrhage and necrotic focus • spleen and kidney swollen • Intestine hyperemic
Pacheco disease Histology • congestion, haemorrhagical and coagulant liver necrosis • eosinofil intranuclear inclusion body
Pacheco disease Diagnostic • clinical sings – feaces and urates of yellow color • X-ray – hepatomegaly • BCH - ↑ of liver enzymes • post mortem, histology – intranuclear IB • proof of virus in feaces or in organs – EM, VNT, ELISA, IF • proof of Ab is not relevant – decreasing regardless proceed latent infection
Pacheco disease Therapy • acyclovir p.o. – best before start of clinical sings • decreasing of mortality • nefrotoxic – with caution nefropathy • supportive therapy
Precaution
• vaccination of birds with high risk – before import (US) (side effects – granuloms, paralysis) • proofing of birds, quarantine
Poxvirus Characteristic • not very often viral disease • hyperplasia of epithelium of skin of head, foot, and mucous of nasal cavity and beak 2 forms: • skin (dry) form • mucous (wet) form • most often in imported canary
Poxvirus Etiology • viruses Avipox family • the greatest viruses (250-300 nm) • enveloped • ds-DNA • replication in cytoplasma • eosinofilic intracelular inclusion body Bollinger body (patognomic) • possibility of latent infection
Poxvirus Susceptible • probably all species of birds • species of family specific • in praxis most often in canary (imports) and free living birds • frequently occurrence in young birds
Poxvirus Transmission •
virus in blood and in the crust
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vectors are primarily latently infected birds
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transmission mainly blood sucking arthropod – mosquitos
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virus in the salivary glands of mosquitos persisted 2-8 weeks
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infection possible to through the eroded epithelium
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outside the body low resistance
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in crust is infected more as one year
Poxvirus Pathogenesis • replication in epitheliun in place of infection • Stimulation of production hormon analogic EGF → synthesis DNA → hyperplasia epithelium • primary viremia → replication in liver (can kill the bird) → secundary viremia → generalisation on the skin and mucous on the body • if the birds survive, than have lifelong immunity
Poxvirus Skin (dry) form •
Canary and free living birds
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fast enlarged mass on the head (around eyes, nostrils and corner of beak), on the leg and on the nake place of body
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scab noduls to multiple great mass
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progressive ulceration and necrotisation
Poxvirus Skin (dry) form • enlarge and diseminate during 1-2 weeks
• if bird survive → in 4-6 weeks spontaneous regression
• permanent effect usually minimal
Poxvirus Mucous (wet) form • canary breeded in outside aviary • import of young of bluefronted amazon, lovebirds, amazónků (Pionus) and mynah • unilateral x bilateral blepharitis • chemosa, conjunctivitis • later difteric inflamation of beak cavity, trachea and erosive lesion of eyelid
Poxvirus Mucous (wet) form • anorexia, dyspnoea • secundary bacterial and fugal infection • birds without therapy often die • past subside can be longtime effect on the eyes (chron. conjunctivitis, symblepharon, cataract, erosion of the cornea, obturation of lacrimal canaly)
Poxvirus Systemic form • acute disease of canary • depresion, dyspnoea, anorexia, die in 2-3 days • skin lesion only in birds, which survive acute phase • extension lesion of air sacs, pneumonia • histologically – proliferation of epithelium of bronchus and bronchiols
Poxvirus Diagnostic •
clinical sings
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post mortem finding
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cytology, histology – Bollinger´s bodys
Poxvirus Therapy •
none specific therapy
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supportive therapy – help birds to survive, the infection they overcome himself
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one time i.m. vitamin A
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ATB, antimycotics – secundary infection
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in anorectic birds rehydratation, feeding with feeding tube
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crusts must fall off
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during rip can be make great destruction of tissue (eyelids)
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past surgical removing possibility of new growing
Poxvirus Precaution • prevent contact with mosquitos • in canary vaccination (canary pox virus) • possibility of vaccination in parrot before import → degresing of mortality • during feeding ill youn, give feeding him as last, especial feeding tube for every bird • hygiene
Chlamydiosis Synonyma • ornithosis • psitacosis Characteristic • Chlamydophila psittaci • in birds unspecifical illness • by weakening or stress • zoonotic potencial
Chlamydiosis Susceptible •
Possible all birds (found in 460 species)
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most common in parrots, pigeons and turkey
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Susceptible too mammals, reptiles and insects
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zoonosis – atypical pneumonia, flu like disease, sometimes neuritis, meningitis and hearth complication
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in birds are problems rarely if are in good health condition (biosecurity, nutrition, stress)
Chlamydiosis Etiology • Chlamydophila psittaci (previously Chlamydia psittaci) • obligate intracelular bacterial parasite • cell wall similar to G- bacteria • inable syntetisate high energic fosfats bonds → required energy from host cells
Chlamydiosis Biology • 2 phase cycle – elementary x reticulary body Elementary body • outside of cell, infectious • metabolically inactive, non multiply • excrete in urine, feaces, exsudate from eyes and respiratory tract • infection via oral or via inhalation → epitelial cells → cytoplasmatic endosom → reticulary body
Chlamydiosis Biology Reticular body • metabolical active, multiplication binare division → great intracytoplasmatic IB with high number of daughter cells→ elementary body → by division of host cell go to the daughter host cells • by desintegration of cell releasing to the buňky do intercellular space or environment
Chlamydiosis Biology •
Chlamydophila defend fusion of endosom with lysosom
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infected cell can be replicated → Chlamydophilla cross to the daughter cells without release of immunogen elementary body → persistent latent infection
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during stress is possible intermittent excreting
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elementary body are little resistant – resistance increased in feaces
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posibility of vertical transmission or during contact between chicken and hens
Chlamydiosis Clinical sings • depended on the strain of Chlamydophilla and species of host and his condition • asymptomatical to grave infection with ↑ mortality • in most cases unspecifical signs • depresion, anorexia, decreasing of body condition, ruffled feathers
Chlamydiosis Clinical sings • by systemic infection of liver, kidney and GIT wattery greenish or yellowish urine and feaces
Chlamydiosis Clinical sings • by affected respiratory system rhinitis, sinusitis, keratoconjunctivitis, dyspnoa and respiratory murmurs
Chlamydiosis Clinical sings • occasionally neural sings – spasm, tremor, opistotonus, paresis of pelvic limbs
• often only decreasing number of eggs and higher mortality of chickens
Chlamydiosis Diagnostic • think to chlamydiosis in DD of each ill birds • in asymptomatical often negative laboratory findings • in clinically ill: • HMT - anemia, leukocytosis, heterofilia, can be monocytosis • BCH - ↑ AST, ↑ LDH, ↑ plasmatic bile acids
Chlamydiosis Diagnostic • RTG, laparoscopy – hepatomegalia, splenomegalia, opacity and thickening of air sacs • postmortem – polyserositis, bronchopneumonia, enteritis, keratoconjunctivitis • spectrum of findings is variabile – but not in all • sampling – feaces, swab from cloaca, swab from conjunctiva, choanal split, naris, samples of liver, splean and kidney (postmortem, bioptical)
Chlamydiosis • postmortem – polyserositis, bronchopneumonia, enteritis • hepatomegaly • splenomegaly
Chlamydiosis Diagnostic • histology, cytology – modification of Ziehl-Nielsen, modification of Gimenez, Machiavelo, IFAT • Inklusion body in spleen, liver, air sacs • staining = screening • Confirmation by cultivation or proof of antigen or DNA • serology – pair sampling → increasing titr Ab • ELISA, LA, komplement fixační test
Chlamydiosis Diagnostic
Chlamydiosis Diagnostic • proof of antigen – ELISA – only for detection of Ch. trachomatis in humans • together with serology have great fault • PCR – extreme sensitivity → risk of contamination of sample or lab • kultivation – cell cultures, embryes • infallible, demanding to the time, finances, facility and labour
Chlamydiosis Therapy and precaution • all birds in contact with positive birds are consider as infected • Infected birds are isolated – especial place, instruments, ideally too others peoples • during manipulation using surgical mask • supportive terapy – attempt restore the body condition of ill birds • minimisation of stress
Chlamydiosis Therapy and precaution • ATB are able kill only the reticular body, but Chlam. can stay in cells long time as elementary body and transfer to the daughter cells → long-lasting therapy • formerly tetracyclins – doxycyclin, OTC, CTC • medication of feed, p.o., i.m. • doxycyklin 45 days • enrofloxacin 7-21 days
Chlamydiosis Therapy and precaution • cell mediated immunity - T-lymfocyts • antibody have not protective impact • Without vaccine (too in humans), which be able protected persistent infection and persistent spreading of chlamydia
Megabacteriosis Characteristic
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yeast disease of sing birds, budgerigards, neofema, small species of conures and cockatiels
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wasting, nondigested seeds in feaces
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infection is possible in greats species of parrots, ostrichs
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detected to in European goldfinch
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↓ production of acids in proventriculus → ↓ function of enzymes → disorder of digestion
Megabacteriosis Etiology • Macrorhabdus ornitogaster • yeast organismus • formerly consider as great bacterial rod • great rod (20-50 μm) • 3-layers wall – outside layer translucent • Gram positive, PAS positive, silver staining • localization in proventriculus and gizzard • cultivation extreme difficult
Megabacteriosis Clinical sings • wasting („going light“ syndrome in budgie) • apathy, inapetention, regurgitation • nondigested seeds in feaces • feaces thin to wattery, dark greenisch or brown- black
Megabacteriosis Diagnostic • cytology → Gram, Diff-Quick • intravitally – feaces, flash from crop → low number • postmortally – scrape off the proventriculus wall
Megabacteriosis Diagnostics
Megabacteriosis Diagnostics
Megabacteriosis Diagnostics • postmortem – finding in proventriculus • often dilatation of proventriculus, strengthen wall • thick turbid layer of mucin of the mucous • bleeding in the mucous
Megabacteriosis Therapy • Acidification of the water – vinegar, mixture of short chain organic acid • easy digestible feed • terbinafin, nystatin, amfotericin B, itraconazol p.o.