Exotics and wild life Flashcards
Test one 5%
How the basic anatomy varies between species ?
Variation of avian species is easily observed in
- length of bones forelimbs / hindlimbs
- crop size eg diet
- choanal slit structure
- length of trachea
Identify and understand the basic external anatomy of the avian head ?
(Identify 1-7)
‘The external anatomy of a birds’ head
- Cere
- Rhinotheca
- Tomia
- the sharp edge of the beak - Gnathotheca
- Rictus
- extremely important where we can observe food build up. - Crest
- Ear covert
- Observing inside the mouth of a bird is an important step during an avian clinical exam - but why ?
- Describe how species may vary ?
Avian clinical exam
Oropharanx what to look for
- observe the choanal slit
- the choanal slit directly communicates with the nares and frontal sinus
- ideal location for sampling or to observe fluid accumulation
additional changes in the specific structure of the choanal slit can relfect disease ( changes in structure, toothed, massive etc).
Oropharanx and species variation
- Toungue and choanal slit can be highly variable between different species
- Tongue hard and rigid in predators, highly prehensile parrots, toothed in geese
Identify the glottis and trachea in this diagram ?
Identification of structures
Glottis (Green)
- opening to the trachea
(Purple)
- opening to the oesophagus
- important to understand how to administer fluids.
Describe the wing structure variation in birds, and the three areas of feather attachment ?
The forelimb - wings
The forelimbs - wings
- the bone structure of wings (even if not used kiwis) remains the same
- the only change between species is in the length of bones
- short humerus, hummingbird
Three areas of feather attachment and their purposes.
Primary
- Come off the phalanges and carpus
- primary lift and power (ENGINE).
- when wing clipping cut first five primaries
Secondary
- come off the ulna
- breaks and steering
Tertiary
- come off the humerus
filling the gap between the body wall and elbow
Coverts
- Second row over each region to cover the feather shafts and streamling the body
What is the Alula in avian species ?
Alula
- equivalent to slats on an aircraft
- can be used to increase turbulance and slow the bird.
Describe how the avian hindlimb is unique, and specific variations between species ?
Avian hind leg
The unique structures of the avian hind limb
- Synsacrum, the hip and sacrum are fused
- femur is typically hidden under the wing
- Fused tibiotarsus, fusion of proximal end of the tarsus with the tibia
- majority of species have four phalanges
Species variation of the hind leg in birds
- there is considerable variation in the length of the femur or tarsus
Identify which species crops a,b, c, d and e belong too ?
Crop
A
- slight dilation
- probable carniovre or ratite
B - granivore such as a budgie / parrot
C - omnivore eg peafowl, magpie
D - Bilobed pigeon
E - Distal dilation duck / cockatoo
Describe the crop and its importance in birds ?
The crop
The crop is a diverticulum of the oesophagus ( a real or potential space).
- a cranial/ cervical portion in the neck running alongside the jugular vein and trachea, the distal portion may or may not be dilated.
- leads to the proventriculus (real stomache)
huge species variation in size, shape and function.
Ducks - distal widening only
Pigeons - well developed / bilobed
Ratites - straight to the proventriculus no dilation
Describe how you could obtain a body condition score of a avian patient ?
Palpation of the keel
- coversmost of the ventral body
- primarily a muscle attachment to the superficial and deep pectoral muscles , attach to the proximal end of the humerus and pull the wing up and down
The keel is important in a clinical situation as it provides a valuable tool for asssessing body condition.
Also covers the majority of the midline body so provides the ideal place for IM injections as there is litle risk to the delicate internal structures of the bird.
Identify the muscles which attach to the keel ?
The keel
pectoralis muscle
Supracoracoideus muscle
Furcula - wishbone, fused clavicle
Coracoid
- fracture of the coracoid may present as a bird unable to fly, but no asymetry / wing droop observed.
What is the most important step in an avian clinical examination ?
History
Possible the hardest part of any consult, getting the information you need while politely ignoring the information they think you need ?
- may be difficult to obtain in a wild bird (typically unknown)
- patient history and problem history
- utilise open ended questions eg what did he eat this morning ?
- obtain information on the backgraound diet, housing, pet interactions, family interactions
- solitary or communal bird
- husbandry varies greatly between species and is often poorly undestood by owners
- History must include = origin, repro, diet and previous issues etc
A good history will assist you in your physical exam
Identify which bird is abnormal and why ?
The bird on the left is healthy.
Birds in health have a concave abdomen
- avian species have a single coelomic cavity (no diaphragm)
- single potential sapce, so changes in any area can be reflected with changes in shape / size of the coelom (readily palpable)
Best to know normal.
What are the three major components of your avian distance exam ?
Avian distance exam
While you are collecting a history observe the unhandled bird / birds.
The three major aspects to consider are;
1. The enclosure
2. Faeces
3. The patient
(healthy droppings pictured below)
What can an avian enclosure tell us ?
The avian enclosure.
What can it tell us, considering most pet birds arrive in their original enclosure
- beware excessively clean cages or carrier cages (wildlife, breeders)
- if they arrive in a different cage ask for a picture of the home cage
- is the cage of a suitable size
- is it designed well
- is it easy to clean
- what materials is it made of
- substrate / floor conditions
During our distant avian exam what can the patient tell us ?
Distant avian exam - the patient
Remeber the majority of species are prey items and they know it
- Masking phenomenon don’t want to be eaten well don’t look sick
- Birds will utilise stored energy, catabolise their protein stores and waste away while trying to appear healthy.
So what might the clinician see
- alertness a healthy bird will be watching you, watching them
- respiratory effort, tail bobbing, chest movements or open mouth breathing
- apetite and thirst
- coordination
- sick bird syndrome, fluffed feathers
During the distant avian exam, what could the droppings potentially tell us about our patient ?
The droppings
In health
- three simple parts
- faeces = food waste (well formed)
- urates = protein waste, processed in the liver excreted via the kidneys (yellow biliverdin)
- urine =liquid waste flushed out via the ureters
- faeces will greatly vary between species depending on health, age, gender and diet
Diarrhoea
- will appear as an unformed faeces component
- watery component (top left = overnight, Centre = not eating, top right = cranberries and bottom typical of a stress defaecation.
Describe the important features of an avian clinical exam ?
Avian Clinical exam
- Handling
- handling use different approaches depending on your patient
- aim for the minimum amount of restraint without looking like a fool
- weighing perch, hand towels, GA may save dramas - Always obtain the birds weight
- weighing perch
- need a starting point for medication doses rates and monitoring changes - Identify individuals sex
- monomorphic, dimorphic species, or DNA / surgical
- important to identify gender specific diseases
- also crucial for perception of knowledge (eclectus) - TPR is unreliable
- temps 40-41, pulse 200-800 and breaths 5-60 - What the clinicain needs to assess
- palpation of the crop and abdomen, which should be concave
- observe around vent
- integument (dermatitis no oozing pus no lysozomal enzyme).
- ceres
Use your history, clinical exam and faeces sample to define your problem.
Identify and understand the basic diagnostic procedures that can be used in avian patients ?
Techniques and specific tricks of the trade ?
Understand and interpretation of results ?
Avian diagnostic testing
Faecal test / fresh smears / stains
- most important diagnostic in avian species; fresh smear first, stained smear and faecal floatation if justified
- fresh faecals first, can always follow on with other stains etc
- minimal sample so there is a thin spread
- allows evaluation of fragile motile organisms that won’t stain
- faecal flotation rarely used except for flock screening / quantitative
Microbiology
- granivores in health mostly gram+ve bacilli, yeast may alo stain gram+ve
- sick bird = monoculture
- gram negative red counterstain
- microbiology, allows appropriate selection of antibiotics based on culture and sensitivity
- gram stain essential in avian/exotic medicine
- crucial relative sizes, contrast
Serology / haematology
- Body’s response to disease
- eryhtrocytes are nucleated
- thrombocytes
- heterophils
Biochemistry
- which organs are affected
Cytology
- Diff Quick
Diagnostic imaging
Endoscopy
Describe sick bird syndrome ?
Sick bird syndrome SBL
Birds present all the same when they are sick
- prey species which are skilled at masking
- until they reach a point when they can mask no longer, and become to ill to hide their illness
This makes diagnostic testing critical for our avian patients.
Identify this test, and what the clinicain is looking for ?
Feather pluck test
- diagnosis for blood parasites
- leukocytozoans dark C formed within reactive white blood cells.
What stain is best utilised to identify cryptosporidium ?
Cryptosporidium - Modified Zhiel Nelson stain
What stain should be used to identify cytological pathology ?
Cytology assessed via Diff Quick
Cytological stain, not usually used for bacterial identification
- all bacteria will appear the same colour and yeasts stain inconsistently.
Describe some issues a clinician must consider when carrying out a blood sample in avian species ?
Blood sample issues avian species
Avian patient size
- most patients are small, yet most comprehensive tests require 0.5ml of blood.
- can only safely obtain 1% of body weight
- needle size selection is crucial
- to big = haematoma, too small may cause haemolysis
- 25-27 guage
Culture and sensitivity
- may take up 2-7 days to get results, which is too late for our patient
- medication may have to be based in the interum on an educated guess
- in house culture may be used to speed up the process
Over interpretation of results
- beware of haemolysis and lipaemia
- take care to treat your patient not the the result
- normal variation can occur in health eg young birds have a higher PCV and lower WCC
- artefacts
Describe the unique features of avian blood ?
Unique Avian Haematology
(similar haematology to mammals)
Unique features
Heterophils
- neutrophils which do not contain lysozymes, and this accounts for why birds do not have liquid pus
- Lymphocytes
- Eosinophils, highly granular
- Monocytes
- Basophils, dark coloured
Eryhthrocytes are nucleated
- polychromasia (variation in cell colour) is common
- shorter cell life so always turning over making polychromasia a regenerative feature common
- anaemia < 40% PCV
Thrombocytes - not platelets
Why must a total white blood cell count be carried out in avian species manually ?
Nucleated red blood cells which means 100% of avian cells will be automatically counted as white blood cells.
What is unique about the avian mechanism of clotting ?
Avian clotting
Birds have thrombocytes
and undergo the extrinsic clotting pathway involving the release of thromboplastin
- this means clotting is induced by tissue damage in avian species, as opposed to mammals where clotting is induced by cutting of vascular channels.
This is important for surgery in avian species
- clotting may be induced by crushing prior to cutting
Identify the cell types in this picture ?
Identify cell types
Blue = heterophil
red = lymphocyte
green = monocyte
Identify the following avian cell types ?
Identify the avian cell types
nucleated cells = eryhthrocytes
blue = thrombocyte
green = basophil
red = heterophil
Identify the avian cell types ?
Avian cell type identification
Dark green = heterophil
Yellow = reactive heterophil
Dark green = basophil
Blue = lymphocyte
Note basophils and eosinophils are commonly not present in a healthy avian blood sample.
- there presence almost always means pathology
- basophils, tissue damage, inflammation or immediate hypersensitivity
- eosinophils = tissue damage usually in avian patients not parasites.
