Anatomy Flashcards
What do bird brains lack making them smooth?
Gyri - bumps and ridges on the cerebral cortex (most outer layer of the brain)
What is a birds most predominant sense?
Why is this?
Sight
Bescuase the optic lobes are found mid brain with the cerebellum
What is the purpose of the cerebellum?
It plays a muscular coordination. Complex body movements required for flight result in a well developed cerebrum in birds.
How many cranial nerves do birds have
12
What reflex do birds lack due to there optic nerves?
Consensal light reflex
This is because the optic nerves completely cross
What is the function on plexus’s?
They send messages from the brain to allow movement
What does the bronchial plexus supply?
It supplies each wing
What does the lumber plexus supply?
Supplies the body wall and upper hind limbs
What does the Ischiatic plexus supply?
Hind limbs - ischiatic nerve
What does the pudendal plexus supply?
Innervate tail and cloacal area
The autonomic nervous system consists of which 2 antagonistic systems?
Sympathetic and parasympathetic
Sympathetic system purpose?
How does it affect
heart rate?
Breathing rate?
Peristalsis?
Intestinal secretions?
Prepares the body for action - fight or flight.
Heart - Increases rate of contraction of cardiac muscle- cardiac output increases
Breathing- smooth muscle of bronchioles relaxes and intake of air increases
Peristalsis- the digestive tract contacts less and peristalsis’s decreases
Intestinal secretions - action on the gland is inhibited- decrease in production of secretions
Purpose of parasympathetic system?
Affects on
Heart rate?
Breathing rate?
Peristalsis?
Intestinal secretions?
Also known as rest and digest - body enters calm state
Heart -Decrease in rate of contraction of cardiac muscle - cardiac output decreases
Breathing-Smooth muscle of bronchioles contracts - intake of air decreases
Peristalsis- Smooth muscle of digestive tract contracts more - rate of peristalsis increases
Intestinal secretions- Action of glands is stimulated - increase in production of secretions
What is rhamphotheca?
It is the keratin layer which covers the upper and lower beak
What is the upper beak keratin known as?
Rhinotheca
What is the lower beak keratin known as?
Gnatotheca
Where is the kinetic joint located and it’s purpose?
It’s where the upper beak connects to skull in parrots
It acts like a hinge mechanism giving the beak more power
What is the purpose of a ducks having fine serration to the edge of their beaks ?
It allows the filtration of fine particles out of the water
How can ducks find food in the water
They have fine nerve endings in the tip of the beaks in a raised structure known as the NAIL
What type of bones do birds have? the larger ones and vertebrae
Pneumonised Bones (hollow bones) that are attached to there air sacks helping air to move through them, helping them to be lighter when flying
where are the scleral ossicles located?
they are small bones which form a ring shaped structure to support the structure of the front of the eye
What are the 2 tear producing glands in birds?
Harderian gland located base of 3rd eyelid
lacrimal gland located caudilterally
What is the fuction of the harderian gland in birds?
it is the dominant orbit - it has a lubricating and cleaning function
it also plays a part in immunity of the eye and upper respiratory tract
how can you use eye colour to determin age in african greys and blue/gold macaws?
uptill 4-5 months = dark grey
after 5 months = yellow/grey turning more silver as bird ages
how can you use eye colour to determin sex in cockatoo’s
Females = bright red/brown iris
Males = dark brown/black
what is the purpose of the pecten oculi?
it is a pleated/folded vascular structure that intermitally contracts expelling nutrition in to the vitreous humour from blood stream - this instead of having blood vessels in the retina.
what type of fibres are within the iris?
Skeletal muscles fibres
what reflexes can you not use to determine ocular function in birds?
pupillary light reflex - due to skeletal muscle fibres they can contract there eyes at will
consensual light reflex - due to complete separation of the optic nerve.
Why can’t you use the humerus in birds for a intraosseous catheter?
Because it’s pneumonised
What colour is the cere for Male and Female Budgies?
Male Blue
Female Brown
Why can a Sinus infection cause problems with Birds with a infraorbital sinus?
The infraorbital sinus connects to air sacs in the head, when they have a infection the narrow inlets between these can become blocked and allow air in but not out of the air sacs leading to over inflation
How many occipital condyles do birds have?
one (mammals have 2)
This makes there necks mobile but weak
what is a ‘Dens’?
The joint within the atlas
the thoracic vertebrae is fused in many species of bird to form a single done known as?
Notarium
There are 2 intervertebral joints between the notarium and caudal vertebrae is know as?
Synsacrum
The fused part of the coccygeal vertebrae is known as?
pygostyle
where do the rectrices attach?
pygostyle
How does the pelvis of birds differ from that in mammals?
The roof is formed by fused lumbar and sacral vertebrae – the synsacrum , which is then fused to the pelvis/ilium.
The acetabulum has no solid bone lining.
An antitrochanter exists - part where the greater trochanter articulates with a ridge in a pelvis
The pubis is unfused and long and thin.
what is the purpose of the coracoid bone?
it put the shoulder joint against the sternum, counteracting some of the large forces created by flapping the wings
Explain the foreman triosseal
its a opening enclosed by the clavicle, scapular and coracoid that muscle tendons pass through
what muscle extends upwards from the keel, through the foreman triosseal and attaches to the dorsal side of humerous?
supracoracoid muscle
what muscle pulls the wing downwards?
pectoralis muscle
what muscle allows elevation on the wing when is contracts
supracoracoid muscle
purpose and location of alula?
1st metacarpal bone
its mobile allowing birds to change airflow over dorsal aspect of wing
Where do the 1-6 primaries attach to?
metacarpal bone
where do the 8-10 primaries attach to?
major digit
where do the secondaries attach?
how many secondary feathers are there?
ulnar
depends on species - ranges from 6-32 feathers
What are tertials?
Refers to feathers that loosely cover space between wing and body
where are covert feathers located ?
they cover the bulk of bird bodies
which bone in the leg can you use for osseous fluid therapy?
Tibiotarsal bone
why can you not use the femur for osseous fluid therapy?
pnemonised
where is suffrago joint located?
between tibotarsal bone and tarsometatasal bone
zygodactyl limb - digit position?
1st + 4th backwards
2nd + 3rd forwards
anisodactyle limb - digit position?
1st backwards
2nd+3rd+4th forwards
which bird has semi zygodactyl?
digit position?
Osprey - possibly to do with catching fish
the 4th digit is mobile - can either be 2nd, 3rd, 4th forwards, 1st digit backwards or 2nd 3rd forward and 1st and 4th backwards
how many phalanges does each digit have>?
digit 1 = 2 phalanges
digit 2 = 3
digit 3 = 4
digit 4= 5
What type of larynx do birds have?
But what do they not have in there larynx?
Rudimentary
Epiglottis, thyroid or vocal cords
What bird form doesn’t have a calcified cartilage in there trachea?
Columbiformes
Why is intubating cranes (and some types of penguins) diffcult?
How can you maintain these species on anaestetic gas?
There trachea splits ventrically into a right and left passage by a midline septrum which may extend from the caudal trachea to just behind the glottis.
You may need 2 ET tubes/circuits, air sac canulars to attach circuit too or maintain gas by face mask
