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Important Avian Diseases. CVM 6882. Overview of Important Avian Diseases. Additional Important Diseases. “Liver Disease” Paramyxoviruses (Newcastle) Adenoviruses Serratospiculosis (Mid-east Falcons) Salmonella Pasteurella. Aspergillosis. Chlamydia. Agent Chlamydia psittaci
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Important Avian Diseases CVM 6882
Additional Important Diseases • “Liver Disease” • Paramyxoviruses (Newcastle) • Adenoviruses • Serratospiculosis (Mid-east Falcons) • Salmonella • Pasteurella
Chlamydia • Agent Chlamydia psittaci • Other C. trachomatis, C. pneumoniae (TWAR) • Character: Intracellular parasite • Infective form: Elementary Body (EB) • Reproductive: Reticulate Body (RB) • Infection: Aerosal, water • Incubation: Days to years • Zoonotic
Clinical Appearance: Classical Psittacosis • Respiratory Involvement: airsacculitis • Leukocytosis, heterophilia, monocytosis • Anemia • AST elevation, TP, bile acids • Hepatomegaly, splenomegaly\ • Fibrinopericardititis
Avian Species Most Affected • Budgerigars • Cockatiels • Amazons • Macaws (most severely affected) • Love birds (endemic) • Pigeons • Not Cockatoos
Psittacosis Treatment • Chlortetracycline Impregnated Pellets -- 45 day treatment required • Oral Doxycycline • Injectable Doxycycline (1/w) • Fluoroquinolones
Diagnostic Dilemmas • Life Cycle of Organism • Stage of disease when sample is taken -- largely unknown • Latency -- may last for years -- no footprints • Variability in virulence • Sensitivity and Specificity of available tests
Diagnostic Tests: 2 types • Antigen Capture • Antibody Detection
Antigen Detection • Kodak Surecell: used on feces, limited supplies • Clearview -- lacks specificity, many false positives • PCR: increased usage (cont. Research) • Growth in Tissue Culture -- gold standard, cultured from tissue or feces • Special stains-- Gieminez
Antibody Tests • Non-available for in-house testing • Grimes Latex Agglutination (he died) • Modified CF Tests -- variable • Numerous Indirect ELISAS • BELISA: direct ELISA -- many false positives
Control in Breeding OperationsE.G. Commercial Cockatiels • Testing - PCR or culture; ( 10 - 20 pairs at end of breeding cycle or birds showing clinical signs) • Frequency: Year 1- every 3 months Year 2 - every 6 months Annually thereafter unless positive result Commence with year 1 after positive result • Positive case - quarantine, treat, retest 4 weeks post treatment • Cull and treat • Test and quarantine any incoming birds
Avian Tuberculosis • Agents: M. avium, M. genovense • World-wide distribution • Chronic ganulamatous disease • Agent is an Acid-Fast Organism • Diagnosis is made by cytological examination of affected organs
TB: Clinical Appearances • Chronic Emaciation: Liver involvement • Subcutaneous Granulomas • Diarrhea: Intestinal Lesions • Dyspnea: Pulmonary Consolidation • Paralysis: Osseous Tubercles
Treatment and Control • Quarantine • Isolation • Depopulation • Antibiotics: not recommended • Isoniazid • Ethambutol
Trichomoniasis • Agents: T. gallinae, gallinarum • Vesogenic, mesogenic, lentogenic strains • Introduced from Europe • Commensal in Columbiformes • Target: oral and pharyngeal mucosa, occasionally respiratory system
Trichomoniasis Continued • Appearance: raised yellow-tan plaques embedded in mucosa, obliterating the choanal slite, palate or base of tongue • Transmission: ingestion of live flagellates • Clinical signs: difficult prehension, swallowing leading to debilitation
Trich: Diffs and Treatment • Differentials: Abscesses, foreign materials, Capillaria spp., Candida • Treatment • Metronidazole: 30 - 50 mg/kg • Carnidazole 10 - 100 mg/kg
Herpes Virus Infections • Marek’s disease - lymphoproliferative, neural disease • Duck plague - enteritis • ILT - chickens • Pacheco’s disease - hepatitis • Inclusion body hepatitis - raptors, cranes, and storks
Herpes of Falcons • Falconid HV-1; closely related to Columbid HV-1, the latter being the source for the former • Clinical: • Lymphopenia • Acute Death • Signs of liver disease
Pacheco’s Disease • Psittacid HV-1,2,3 • South American Origin • Cockatoos and Amazons die peracutely • Macaws die acutely • Conures (Nanday and Patagonian) incriminated as carriers, but ……...
Management of Herpes Virus • No effective individual treatment although acyclovir will reduce death rate in an aviary • No vaccines available • Hygiene and Sanitation • Gyrfalcons and pigeons don’t mix
Pox Viruses • DNA Virus -- many strains • Falcon Pox • Pigeon Pox • Fowl Pox • Peacock Pox • Canary Pox (most pathogenic) • High degree of host specificity
Clinical Aspects • Transmitted by biting insects - virus can live in salivary gland for several weeks • Disease Forms: • Epithelial Crusts • Diphtheroid - Wet pox • Septicemic form -- Canary Pox
Treatment of Pox • Debride or cauterize lesions • Control secondary bacterial infections • Selective Vaccination • Canary • Chicken • Turkey • Others -- see Ritchie, Harrison, Harrison
Macaw Wasting Disease • Proventricular Dilatation Syndrome • Viral Etiology confirmed • Neurotropic • Myenteric Plexus of Mid g.I. Tract • Crop • Other neural tissue
Macaw Wasting • Species: all psittacines, contagious • Signs may not appear for several months after exposure • Signs: slowing g.I. Tract, undigested seeds in stool, cachexia,, dehydration, death • No treatment, no vaccination • Aviaries: depopulate
Paramyxoviruses: Newcastle (VVND) • Newcastle: PMV-1 • PMV2-9: PMV-3 causes mild neurologic signs in pigeons Clinical • Signs: • Diarrhea, respiratory signs followed by neurologic signs (torticollis)
Budgerigar Fledgling Disease:Polyoma Virus • Highly infectious, stable • Causes • Budgerigar Fledgling Disease: peracute death with near 100% mortality in birds < 15d • French Molt: feather dystrophy syndrome • Polyserositis in other psittacines with bleeding syndromes
Polyoma (cont) • Diagnosis: • Feather lesions indistinguishable from BFD • Antemortem: Cloacal swab and culture • Postmortem: DNA probes • Control • Isolation of shedders away from neonates • Control feather dust and other hygiene • Vaccinate -- killed vaccine available
Beak and Feather Disease • Circovirus Disease • Septicemia and peracute death in nestlings • Beak Necrosis,Feather Dystrophies, worsening with each successive molt • Endemic in wild cockatoos (Australia) • Also will infect New World Parrots
Beak and Feather (cont) • Diagnosis: Signs, biopsy, DNA Probes • No treatment, no vaccination • No spontaneous recovery; affected birds die from secondary problems
Infectious G- Bacteria Chlamydia Mycobacteria Viruses: Herpes Adeno Polyoma Reovirus Trematodes (esp. cockatoos) Non-Infectious Aflatoxicosis Fatty Liver Iron Storage Disease Neoplasia Protozoal Toxoplasma Trichomonas Histomonas “Liver Disease”: Causes
Physical and chemical Elevated AST, CK, Bile Acids G. I. Stasis Feather abnormalities Chronically overgrown beak and claws Hepatic Encephalopathy Clinical Weight loss Weakness Ascites Biliverdinuria Melena Coagulopathy Liver Disease Signs:
Liver Disease Treatment • Fluids • Hyperalimentation • Lactulose • Antibiotics • Doxycycline • Enrofloxacine • Metronidazole or Clindamycin • Other Specific Chemotherapy as indicated