Midsemester 1 Flashcards
List some common diagnostic tests
Microbiology: infection presence (mostly G+, G- overgrowth= enteritis), resistance, antibiotic choice
Culture and sensitivity: ID organism and therapy
Haematology and biochemistries
What are the techniques used for haematology?
1% birds BDW in blood
25g
Blood smears immediately
Paedeatric lithium heparin or EDTA- centrifuge and decant plasma in another lithium heparin for lab biochem
insignificant:
- low bile acids
- high amylase (needs to be >15X)
- lipaemia: artifact, bad diet
- haemolysis- artifact
- high uric acid in periguin falcon (high protein)
- lower PCV and higher WBC in young
What are the characteristics of erythrocytes?
Erythrocytes: nucleated
- PCV (~40) lower in chickens compared to parrots (increased O2 capacity with flight)
- morphology: strongly regenerative if mitotic figures, reticulocytes regen, Non regenerative anaemia= chronic dx, overwhelming infection or nutritional
What are the characteristics of white blood cells?
WBC: manual count (nucleated RBC cause high counts)
- 40X: (no. WBC in 10 fields/10) X 2000
- heterophil- neutrophil without lysosyme->caseous pus
- eosinophils rare (tissue damage, parasite)
- monocytes- common
- lymphocytes- small or large
- basophils uncommon (tissue damage, inflam, hypersensitivity)
Leukocytosis:
- Normal: juvenille
- stress leukogram: 90% heterophil and 10% lymphocytes
- inflammation: similar and then monocytosis and basophilia
Leucopenia: (heteropaenia)
- chronic BM suppression
- overwhelming BM
- artifact
Lymphocytosis:
- leukaemia
- chronic inflammation
- normal
Lymphopaenia:
- overwhelming infection
- relative to heterophilia
Monocytosis:
- chronic granulomatous dx: abscess, TB
- no monocytopenia (values 0-1)
What are the characteristics of thrombocytes?
Thrombocytes:
- extrinsic clotting factor (no platelets)->release thromboplastin
- anti-inflammatory role
- phagocytic
List the biochemicals
Metabolites:
- uric acid (end product of protein digestion)
- protein
- cholesterol (liver from fat and carbohydrate)
- triglycerides
- urea (end product of protein digestion)
Enzymes:
- AST
- CK
- GLDH
- Amylase
Minerals:
- Calcium
- phosphorous
Electrolytes:
- Na, Cl, K
Bile acids
Liver disease biochem:
Hepatic necrosis: AST (+CK) and GLDH (mitochondria in hepatocytes)
Liver function: bile acids (rising levels= less entero-hepatic uptake) and cholesterole (energy source, significant if rising)
Cholestasis:
- GGT (bile occlusion, carcinomas)
Renal disease biochem
Decreased function: uric acid (produced in liver from protein->passed out through tubules-> elevate)
Hydration status: urea (over 1-2)
Reproductive disease biochem
Calcium: hypocalcaemia from eggs
Cholesterole: yolk
Triglycerides: yolk
Total protein: transport
GIT dx biochem
Na, Cl, K, amylase (broad)
Blood glucose biochem
Hyperglycaemia: DM (>33, persistent), stress, normal (artifact- RBC left in contact with plasma)
Lipids biochem
Cholesterol:
- hepatic lipidosis
- artherosclerosis
- diabetes mellitus
- hypothyroidism
Triglycerides:
- repro
How to interpret PCR:
High spec, sens detecting Ag not disease
- Ag can be intermittently shed, or at low []
False results:
- contamination of sample (feather from floor)
- inhibitors
- previous drugs- doxycycline for chlamydia->N- after 2 days
How to interpret serology:
Combine with PCR and do serial testing (accuracy), Detect Ab affected by: - host factors- ab levels - antigen factors- prepatient levels - assay factor- selection
Blood- low invasiveness, cheap
Use:
- flock outbreaks
- Specified Pathogen Free (poultry)
- immune status or individual
Interpreting cytology
FNAB, centesis, impression, washes
- cell type: haemic cells (blood and haematopoetic tissue)
- epithelial cells exfoliate easily- abundant in cytoplasm
- nervous tissue rare (basophilic, stellate)
Cell response:
- inflammation
- tissue hyperplasia
- benign neoplasm: mitotic figures, cytoplasm, unipopulation
- malignant
Interpreting radiology
Radiology:
- short exposure time, relatively powerful, high detail screens and films
- digital
- birds under 50g- dental machines (better exposure)
- birds over 50g- normal machine
Restraint:
- box- looking for egg
- anaesthesia- face mask, sedate with midazolam
- plexiglass
Positioning:
Lateral:
- wings dorsal and cranial (superimpose coracoids)
- legs: caudal and dorsal (superimpose acetabular)
- carina of keel parallel to plate
Ventro-dorsal:
- anaesthetised
- wedge head up on foam, won’t regurgitate
- wings: foam support underneath and sandbag on top
- legs: parallel to tail
- carina superimposed over spine
-
Interpreting ultrasound
Cheaper, less commonly used air sacs interfere USE: - yolk peritonitis - GIT dilated full of ingesta - nodules - abdominal distension
Interpreting computer tomography
Very useful, $$, need radiographer
Very detailed
Use:
- Ovary enlarged in breeding season->pressure on abdomen->herniate
- Jaw fractures in snakes- useful to show owner 3D
Interpretation of fluoroscopy
Real time - GIT motility studies
Place bird in dark box
Use:
- vomiting or dilated proventriculus on rads
- proventricular dilation disease: backflush from oesophagus back into crop
- obstruction: ingesta moving to proventriculus but not ventriculus
will burn bird if prolonged exposure
Interpreting endoscopy
Anaesthesia
Examine internal organs:
- pericardial effusion (can’t detect on rads), lungs, kidneys, ureters, spleen, adrenal glands, GIT, fungal granulomas on air sac- biopsy
External opening:
- mouth- trachea->syrinx
- Ear- pinnae small
- Cloaca- expand with saline to allow passage, opening of ureters, oviduct, urodeum, proctodeum, (papillomas)
Biopsy: 1.9mm, 2.7mm
Feather function and normal feather loss
Flight, communication, waterproofing, insulation
Feather loss:
Moulting: thyroid gland, diurnal cycle and photoperiod control
- spring and autumn (pre and post nuptial moult/breeding)
- few feathers at a time, bilaterally symmetrical
Describe stuck in moult
Canaries or high producing chickens
Inappropriate diurnal exposure
Malnutrition: no energy to moult. dull colour, feather damage, feather loss
Treatment:
- distinct diurnal cycle (dark room 8-12 hours) and correct diet->usually triggers moult
- desorelin implant last resort
Traumatic feather loss causes
Predator avoidance
social
self-inflicted
nesting- want chicks out
Infectious causes of feather loss: parasites
Parasites:
- over diagnosed
Mites:
->cnemidocoptes: scaly faced mite, scaly leg mite
- pinholes from proliferative reactions in keratin
- Ivermectin fortnightly X 3 via crop (28d WHP)
- > red mite: nocturnal, blood feeding, common
- > Fowl mite: very common,
- pyrethrin (2 week WHP)
Lice
Infectious causes of feather loss: bacterial and fungal
Secondary to trauma
- self trauma: Quaka mutilation syndrome
- cockatoo: axillary dermatitis
- Ringworm/favus (uncommon): biopsy, griseofulvin, itraconazole, wash with enilconazole shampoo
Psittacine beak and feather disease
All parrots susceptible, new world’s are resistant and rare in cockatiels
- basophilic cytoplasmic inclusion body
- juvenilles
- incubation: 21-25 days->years
- shed in faeces, crop secretion and feather dust
- incurable
CS:
acute:
- juvenilles
- lethargy, weakness suddenly
- regenerative anemia, pancytopaenia
- death 24-48hours
- severe hepatic necrosis
Chronic:
- cockatoos
- feather: loss of primaries (lorikkeets) and colour chanegs
- beak: overgrown, underrun, necrotic (constant pain)
Other parrots: colour change, feathers fall out if handled, untidy (feather dystrophies)
Diagnosis:
- histopathology
- dead- send cloaca
- feather- pluck
- serology; haemaglutination, haemaglutin inhibition test
- PCR: blood from blood feather- immune response
Treatment:
- avian interferon- experimental
- supportive care
Prognosis:
- some can effectively recover (lorikeets)
- some live 10-30 years despite CS
- mostly die ~2 years- immunocompromise
Avian polyomavirus
All parrots. mostly budgerigars, macaws, conures, eclectus parrots, caiques (rarely african grey parrots, cockatoos, cockatiels)
- Viraemic form: dead in 1 day, viral inclusion bodies
- necropsy: haemorrhage (pale carcass), liver destroyed, severe coagulopathy- easy bruising
Feather forms:
- drop primary wings and tail
Diagnosis:
- histopath
- PCR: blood (viraemic form in circulation) and cloaca (needs to be cleared in droppings)
Treatment: none
- most die, budgies can regrow feathers and live
- burn all nest boxes and stop breeding for 6 months
Feather damaging behaviour- disease of captivity
Causes:
- underlying pain: internal organ pain
- dermatitis
- underlying lesions
- malnutrition
- psychological problems: anxiety, boredom, fear, breeding
DX: - rule out physical - CBC, biochem, skin biopsy and culture - radiology - find out bird habits when physical ruled out; Antecedent (what preceds the behaviour) Behavioural Consequences
TX:
- only use collars if skin is broken, don’t sedate
enrichment plan:
- 80% foraging for food and 20% social and napping
- foraging, physical, sensory, social (indirect and direct), occupational
Describe the anatomy of the upper respiratory tract in birds
External nares->rhinal cavity
Nasal cavity (turbinates for smell)
Infraorbital sinus: ordour, humidify
- cervico-cephalic air sac: thermoregulation and buoyancy
Choana glottis-
Glottis- vertical slit opening laterally, arytenoid cartilage and no epiglottis. appose choanal slit (allow breathing)
Trachea: complete interlocking cartilage rings for strength and flexibility, longer and wider than other spp. Diameter decreases
Syrinx: diving two bronchi, voice production (site for obstruction of aspergillus granuloma)
Lungs: Dorsal (paleopulmonic) and ventral half, paired, fixed, recessed between ribs
air sacs:
- caudal to lungs: cranial thoracic and abdominal
- cranial to lungs: 2 cervical and intraclavicular sac
no diaphragm, push d sternum down, pivoting down on coracoid joint and ribs move out->air drawn into lungs and caudal sacs, sternum moves up and ribs come in->air through to cranial sacs (neopulmonic part) into lung and expired
Clinical signs of upper respiratory tract
Sneezing Staining of feathers above nares Sinus distension- infraorbital Occular discharge Matting of periorbital feathers Periocular alopecia Thickening eyelids SQ emphysema if cervicocephalic air sac is ruptured
Trachea: acute
- coughing
- open mouth breathing
- neck stretching
- resp noise (air over exudates)
- distress
Lung and air sacs: chronic
- increased resp effort
- mouth breathing
- tail bobbing (inspiration)
- sternal lift
- weight loss
