Comparative Anatomy Study Notes

Welcome: Participants welcomed to the two-month program.
Housekeeping: Reminder for students to change their Zoom names to their full names and school initials for identification purposes.

Speaker: Dr. Errol J. Y. Balagan, assistant professor and chair of the department of morphophysiology and pharmacology.
- Education:
- BS in Animal Husbandry, Cum Laude, Central Lausanne State University (2009).
- Doctor of Veterinary Medicine, Magna Cum Laude, Central Lausanne State University (2011).
- MS in Comparative Vertebrate Morphology, University of Antwerp, Belgium, Summa Cum Laude (2018).
- Achievements:
- Second place in Veterinary Licensure Examination (2011).
- Erasmus Mundus Scholarship recipient for his Master’s program.
Lecture Content:
- Gross Comparative Anatomy Part 1 covering osteology, myology, and arthrology with a focus on osteology this session.

Classification of Bones: Bones can be classified based on shape:
- Long Bones: E.g., femur, humerus, radius, ulna, tibia, fibula.
  - Characteristics:
  - Cylindrical shaft called diaphysis.
  - Ends called epiphysis.
  - Growth area between epiphysis and diaphysis known as physis (important for lengthening of the bone).
- Short Bones: E.g., carpals and tarsals.
  - Function: Reduce friction.
- Flat Bones: E.g., skull, scapula, pelvis.
  - Function:
  - Protect organs (e.g., brain).
  - Muscle attachment.
- Irregular Bones: E.g., vertebrae.
  - Function:
  - Support and ligament attachment.
- Pneumatic Bones: Unique to birds, adapted for flight, lined with mucous membrane instead of bone marrow.
- Aberrant Long Bones: E.g., ribs classified in some older texts.
- Sesamoid Bones: E.g., patella.

Axial Skeleton: Bones at the axis of an animal (e.g., skull, vertebrae).
Appendicular Skeleton: Bones of appendages (thoracic and pelvic limbs).
- Includes structures like splanchnic bones, which are embedded in soft tissue (e.g., baculum in dogs, os cordis in cats).

Skull Division:
- Cranial Part: Protects the brain (cranium).
- Facial Part: Protects respiration and digestive structures.
Identification of Major Bones:
- Maxilla: Forms lateral wall of the face, contains infraorbital foramen.
- Frontal Bone: Forms rostral roof of the cranium.
- Lacrimal Bone: Located in the medial-lateral part of the orbit.
- Palatine Bone: Forms part of the hard palate.
- Zygomatic Bone (Jugal/Mallar Bone): Forms cheekbone, contributes to zygomatic arch.
- Nasal, Incisive, Parietal, and Temporal Bones: Important for defining the anatomy and function of the skull.
Occipital Bone: Unpaired bone, includes structures like occipital condyles that articulate with the cervical vertebra (atlas).

Joints Overview:
- Importance of various processes and structures, such as the tympanic bulla which houses middle ear bones: malleus, incus, stapes.
Mandible Anatomy:
- Parts: Body, ramus.
- Processes: Coronoid, condyloid, angular processes.

Hyoid Apparatus:
- Position: Intermandibular space.
- Parts: Stylohyoid, epihyoid, ceratohyoid, basihyoid, thyrohyoid (identified using mnemonic: Sick Elephants Can Be Treated).
Vertebral Column: Composed of vertebrae arranged along the midline of the body.
- Vertebral Formula for Common Animals:
- Horses (18 thoracic vertebrae), Dogs (13), Cattle (13), Pigs (varying).
- Parts of a Vertebra: Body (cylindrical mass), vertebral arc (pedicle, lamina), processes (spinous, transverse, and articular).

Joints between Bones: Identification of bones forming stifle, elbow, proximal interphalangeal joint, distal interphalangeal joint, and their articulation.
Joint Functions: e.g., Metacarpophalangeal Joint - within fetlock and other key joints among various animals.

Components of the Thoracic Limb:
- Scapula (shoulder), humerus (arm), radius and ulna (forearm), carpals, metacarpals, digits.
Scapula Anatomy: Medial/lateral surfaces, fossa, and borders relevant to muscle attachment.
Humerus Anatomy: Proximal end (head, tubercles), distal end (condyle, fossa), structures unique across species.

Carpal Bones: Comprised of two rows of bones with specific names and functions.
- Different configurations in dogs, pigs, and ruminants for efficient locomotion are discussed.
Tarsal Bones: Two rows of tarsal bones (e.g., tibial tarsal - talus, fibular tarsal - calcaneus).
- Identification of these in dogs, horses, and ruminants, including anatomy related to movement.

Classes of Joints: Their structures and functions, including degrees of movement (synovial joints, fibrous joints, cartilaginous joints).
- Classification Examples: Hinge joint (elbow), ball-and-socket joint (shoulder), etc.
Functionality: Joints facilitate movement and support a variety of physical activities in animals.

Upcoming discussions will cover aspects of splanchnology with a focus on the digestive, respiratory, and urinary systems, followed by reproductive and nervous systems.
Reminder on Zoom etiquette and resource sharing for additional learning support.