Gallus domestica
CLASS AVES
CLASSIFICATION
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Galliformes
Family: Phasianidae
Subfamily: Phasianinae
Genus: Gallus
Species: Gallus gallus
Subspecies: G. g. domestica
GALLUS GALLUS DOMESTICA
EXTERNAL PARTS OF THE CHICKEN
CHICKEN EYES AND NOSTRILS
Eyes
attached are also much bigger than in mammals such as humans.
Orbits are made of many small bones that merged together. They made a thin plate.
Nostrils
Located at the end of the beak
EYELIDS
Chickens have 3 eyelids:
upper eyelid
Lower eyelid
Nictitating membrane
NICTITATING MEMBRANE
transparent or translucent third eyelid
can be drawn across the eye
for protection and to moisten it while maintaining visibility
to protect the parents' eyes from their chicks while they are feeding them
BEAKS AND EAR OPENINGS
Have a pointy beak for picking up food
No teeth are present Located at the sides of
their head behind the eyes
covered by feathers
are more like ear holes
No outer ear, or pinna
They have visible ear lobes
It is believed that the same gene that determines the color of the ear lobe also determines egg color.
Their ear lobes also can be colored from near white to near black. These birds will lay eggs that are nearly white to a deep, soft brown. The shade of brown of the egg will be indicated by the degree of color of the ear lobe. In other words, a chicken with blackish lobes will not lay a black egg, but it may be a deep brown.
WATTLE
Wattles are located under the chin.
They are meaty, red growths.
Both male and female chicken have wattles.
wattles cools down the chicken.
This happens when the blood circulates from the comb to the wattles. The circulating blood lowers the temperature of the chicken during the hot weather.
COMB
fleshy protuberance on top of the head of a chicken
the cockerel have a larger comb than the hen chicken
act as a cooling mechanism for the birds
large combs on males attract females as chickens can detect colour and are very attracted to the colour red.
serves as an indicator of the bird’s health.
TYPES OF COMBS
THE FORELIMB
THE FORELIMB
The bird’s wing and is responsible for powered flight.
Primarily supported by an elongated radius, ulna, and modified wrist bones.
THE FORELIMB
THE FORELIMB
Upper Arm
Short and stout humerus
Connects the scapula with the lower arm (or forearm)
Provides the musculature necessary for flight
THE FORELIMB
THE FORELIMB
Forearm
Composed of an elongated radius and ulna
Serves as attachment point for flight feathers
Reduced wrist flexion
THE FORELIMB
THE FORELIMB
Manus
The phalanges of the bird wing follow a trend of reduction and fusion to form the distal part of the wing
Modern birds have mostly only the second digit of the hand present
THE FORELIMB
THE HINDLIMB
THE HINDLIMB
Composed of the thingh, shank and foot.
Enables bipedal locomotion for birds.
THE HINDLIMB
Thigh
Upper portion of a bird’s hindlimb
Composed of a short femur.
THE HINDLIMB
THE HINDLIMB
Shank
Lower portion of a bird’s hindlimb
Composed of the tibiotarsus (fused tarsus and proximal part of the tibia).
THE HINDLIMB
FOOT AND REMIGES
FOOT
1. Hallux or hind toes
2. Inner toe3. Middle toe4. Outer toe5. Scales6. Reticulate
scales
REMIGES
PTERYLAE
Region on the chicken skin where feathers grow
Symmetrical tracts
Separated from each other by semi-apteria
Feather macropattern
APTERIA
Bare area(feathers don’t grow) on the chicken skin
Spaces between the feather tracts of birds
Covered by down or semi-plume feathers