Ruminants Anatomy - Dr. Brahmbhatt`s Class Handouts

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Transcript Ruminants Anatomy - Dr. Brahmbhatt`s Class Handouts

Ruminants Anatomy
In Hinduism, the
cow is a symbol of
wealth, strength,
abundance, selfless
giving and fully
earthy life
• Musculoskeletal
Bovine Skeleton
7, 13, 6, 5, 18-20
Types - bones
vertebrae
and certain facial bones
carpal and
tarsal bones
sternum, ribs,
scapula,
and certain skull
bones
humerus, radius, femur,
tibia,
metacarpals, and
metatarsals
patella,
and proximal and
distal sesamoid
bones of the
digits.
Cow and Sheep Skull
• The brain is situated within
the cranium - a box-like
posterior part of the skull.
• The brain is connected to
the spinal cord through a
large hole, the foramen
magnum.
• The foramen magnum is
flanked by two large knobs
or occipital condyles that
form a joint with the first
cervical vertebra of the neck.
• Sinuses or spaces are
present between the inner
and outer cranial walls.
Meningoencephalocoele
Nasal sinus: MCF
Digital section of head with removal of nasal septum, showing
accumulated fibrinous secretions lodged in the anterior portions
of the left nasal turbinates (arrow).
• Coronoid process is located medially to the zygomatic arch
Process allows muscle leverage to be exerted onto the mandible
Mandibular condyle: joint between the skull and the lower
In cattle and sheep, the mandibular condyle is relatively flat and
allows considerable movement in a horizontal
plane.
Lateral movement is important in animals whose teeth work with a grinding
action.
• Ruminants such as
cattle, sheep and goats
are herbivores with a
unique digestive
system.
• A prominent feature of
ruminant dental
anatomy is that they
lack upper incisors,
having instead a
"dental pad", as
shown in the image to
the right of a goat.
DENTAL FORMULA
Species
Dental Formula
Total # teeth
Canine - puppy
313
313
28 (NO MOLARS)
Canine - adult
3142
3143
42 (EXTRA MOLAR ON
MANDIBLE)
Feline - kitten
313
312
26
Feline - adult
3131
3121
30 (EXTRA PRE-MOLAR
ON MAXILLA)
Equine - adult
3133
314/33
40 0r 42
Porcine - adult
3143
3143
44
Bovine adult
0033
3133
32 (NO UPPER INCSORS
– DENTAL PAD)
Dental Formulae
003
Deciduous
3 1 3 =10
0033
Permanent 3 1 3 3
=16
The dental anatomy of all ruminants is similar
• In the dental formulae shown above, cattle are depicted as
having 3 incisors and 1 canine tooth. Some authors prefer to
state that they have 4 incisors, with the canine tooth refered to
as the fourth or corner incisor.
• Llamas*
Llama and Alpacas
Maxilla and mandible, llama. Maxillary teeth shown are the third incisor and
canine. Mandibular teeth shown are I1-I4. The llama fighting teeth are the
upper third incisors, upper canines, and lower fourth incisors (six total
teeth). The fighting teeth Courtesy of Dr. Bradford B. Smith and Dr. Karen I.
Timm
Tooth Eruption
Deciduous
Permanent
Incisors
Birth - 2 weeks 18 - 48 months
Premolars
Birth - 1 weeks 24 - 36 months
Molars
• CD
6 - 30 months
Maxillary Arcade
• Note the lack of
incisors
Maxillary Arcade
(Lateral view)
Mandibular Arcade
Mandibular Arcade
(Lateral view)
The wide gap that separates the incisors (or
dental pad on the maxilla) from the premolars
is called the diastema.
• The vertebral column or backbone
is the main axis of the skeleton and it
protects the spinal cord.
• The spinal cord is located in a neural
canal formed by a long series of
neural arches, each contributed by a
different vertebra.
• The neural arch of each vertebra is
supported on the body or centrum of
the vertebra. In some types of
vertebrae, the neural arch extends
dorsally as a prominent spine that
may be called a dorsal spine, a
neural spine or a spinous process.
Abscess of vertebral body
types of vertebrae
•
•
•
•
•
•
NAME--------REGION---------BEEF--------------LAMB
Cervical--------Neck------------------7-----------------------7
Thoracic-------Ribcage---------------13---------------------13 to 14
Lumbar--------Loin--------------------6----------------------6 to 7
Sacral ---------Sirloin------------------5----------------------4
Caudal---------Tail--------------------18 to 20--------------16 to 18
assist the extensor
muscles of the head
and neck, extending
from the occipital
bone to the spinous
processes of the
thoracic vertebrae
Plan of neck in beef, showing:1, ligamentum nuch; 2,
atlas; and 3, axis. The ligamentum nuchae is pale yellow
• The first cervical vertebra, the atlas, articulates with the skull
and is greatly modified in shape to form a joint that enables the
animal to nod its head up and down.
• Rotation or twisting of the head occurs from the joint between the
atlas and the next cervical vertebra, the axis.
• The ligamentum nuchae is a very strong elastic ligament in the
dorsal midline of the neck, and it relieves the animal of the weight
of its head. Were it not for the ligamentum nuchae, the head of
the standing animal would droop between its forelimbs
Contagious Bovine Pleuropneumoniae
Exposed Atlanto-Occipital joint with severe thickening
of the meninges and fibrin deposits
Ribcage
• The cage formed by thoracic vertebrae, ribs and
sternum is an essential component of the
respiratory system.
• Thoracic vertebrae are distinguished by their tall
dorsal spines, many of which point towards the
hindquarter and are known as the feather bones.
Comparative Vertebrae
Cervical
Thoracic
Lumbar
Sacral
Coccygeal
Canine/
Feline
7
13
7
3
6-23
Equine
7
18
7
5
15 - 21
Bovine
7
13
6
5
18 - 20
Porcine
7
14 - 15
6-7
4
20 - 23
Ovine
7
13
6–7
4
16 - 18
The structure of the ribcage is rather variable in
lamb carcasses
BEEF----------LAMB
Total pairs of ribs-------------13--------------13 to 14
Pairs of sternal ribs-----------8----------------8
Pairs of asternal ribs----------5---------------5 to 6
Number of sternebrae--------7---------------6 to 7
Pelvis
• The pelvis and the sacrum
form a ring of bone
completed ventrally by the
pubes.
• The left pubis is separated
from the right pubis by
fibrocartilage which, at
parturition, may soften to
allow movement between
the bones of the pelvis.
• The pubes are separated
V
when carcasses are split into
left and right sides in the
abattoir.
Plan of the pelvis in a hanging beef carcass
showing:1, lesser sciatic notch; 2, ischiatic
spine; 3, greater sciatic notch; 4, psoas tubercle;
5, obturator foramen; 6, symphysis pubis;7,
ischium; and 8, ilium.
Pubic
The tuber coxae forms the basis
of the point of the hip (hooks)
Another plan of the both sides of the pelvis in a hanging carcass showing: 1, tuber
coxae; 2, acetabulum; 3, acetabular ramus of ischium; 4, tuber ischii;
5, symphysis pubis; 6, ilium; 7, pubis; and 8, ischium
OS COXAE - PELVIS
The pelvic girdle comprised of the
illium, ishium, and pubis. This is
the largest of the the flat bones
Ilium – Ischium - Pubis
• The largest and most anterior of the
three parts of the pelvic girdle
• Hip bone/ Pin bone
• Smallest of the three parts of
the pelvic girdle
Aitch bone – Body of shaft of Ischium
• The aitch bone is curved in steer and
bull carcasses, is moderately curved in
heifers, but is straight in cow carcasses
Forelimb skeleton -Scapula
• The scapula is not fused to the
vertebral column (like the pelvis
in the hindlimb), and this allows
muscles that hold the scapula to
the ribcage to function as shock
absorbers during locomotion.
• The scapula has a distal socket
joint for the next bone in the
forelimb, the humerus.
• This socket of the glenohumeral
joint is called the glenoid
cavity .
– The glenoid cavity is wide and
shallow, unlike the ball and socket
joint in the hindlimb which is
narrow and deep.
ACROMION
• On the lateral face
of the scapula is a
prominent ridge of
bone called the
spine of the
scapula.
– In beef (OX)
carcasses, the
scapular spine is
extended distally
as a prominent
acromion
process.
Humerus – “Arm bone / clod bone”
• Proceeding distally down the forelimb, the bone that
articulates with the scapula is the humerus.
• Proximally, the humerus has a relatively flat knob or
head to fit into the glenoid cavity of the scapula.
Two well defined condyles on the distal end of the
humerus contribute to the hinge joint at the elbow.
Radius & Ulna: (‘Foreshank bone’)
Beef shankbones showing: 1, distal end of humerus; 2, olecranon
fossa; 3, olecranon process;, 4,radius; 5, ulna; and 6, carpal bones.
• The radius is joined to the ulna and is
the shorter and more anterior bone of
the pair
Femur – ‘Round bone or leg bone’
• The proximal bone of the hindlimb is the femur or
round bone. The articular head of the femur is deeply
rounded and it bears a round ligament that holds it
into the acetabulum.
• Another distinctive feature of the femur is the broad
groove between the two trochlear ridges
located distally. The patella or knee cap slides in
this groove
Tibia – ‘hind shank – hock bone’
• In beef and lamb
carcasses there is a
single major bone,
the tibia or shank
bone, located
distally to the femur.
• Tibia and fibula
1, medial condyle,
2, lateral condyle;
3, tibia, and
4, fibula.
Congenital
Cloven (split) hoof: Cattle/ goat/ sheep
2 digits: III and IV with 3 phalanges. Digits II and V: vestiges
Erosion on the foot caused by FMD
or Vesicular Stomatitis which are
grossly indistinguishable from one
another.
References
• http://w3.vet.cornell.edu/virtualvet/bovin
e/tissue_lesions.aspx?Tis=37
• http://bovine.unl.edu/bovine3D/eng/nInt
ro.jsp
• http://studentvet.wordpress.com/2010/0
7/29/bovine-forelimb/#Humerus
• McBride Douglas, Learning Veterinary
terminology, 2002
• http://vetmed.illinois.edu/courses/imagin
g_anatomy/bovine/hindlimb/foot/ex01/e