Anatomy and Physiology of Farm Animals Lecture Notes

Anatomy and Physiology of Farm Animals  Latin word “ana” “tome”  “ana” – again or go back  “tome” – to cut  “cut again” or “go back and cut”  The study of the structure of the animal body and the relationships of its many parts Physiology  Study of function of the parts or o...

Anatomy and Physiology of Farm Animals  Latin word “ana” “tome”  “ana” – again or go back  “tome” – to cut  “cut again” or “go back and cut”  The study of the structure of the animal body and the relationships of its many parts Physiology  Study of function of the parts or organ systems of the body  Study of function of living matter  Explains the physical and chemical factors responsible for the origin, development and progression of life  Provides knowledge on the structure and function of the body, and constantly, the care of the body  Homeostatic: maintenance of static and constant conditions in the body  Anatomy The study of the structures of living things  Physiology The study of the functions of living things Mechanical, physical, or biochemical  Gross (macroscopic) anatomy – forms and relations of the structure of the body which can be seen with an unaided eye Comparative anatomy –structure of Definition various species of animals with particular emphasis on those of Terms characteristics that aid in classification Embryology - developmental anatomy covering the period from conception (fertilization of the egg within the female) to birth  Histology (microscopic anatomy) - tissues and cells which can be seen only with aid of microscope  Systematic anatomy approach – anatomy by systems Systematic Anatomy - Study System Name of Study Chief Structure Circulatory Angiology Heart, blood system vessels Articular system Arthrology Joints Integumentary Dermatology Skin system Endocrine Endocrinology Ductless gland system System Name of Study Chief Structure Sensory system Esthesiology Eye, ear Muscular Myology Muscles system Nervous Neurology Brain, spinal system cord, nerves Skeletal system Osteology Bones System Name of Study Chief Structure Digestive system Stomach and intestines Respiratory system Lungs and air Urinary system Splanchnology passages Reproductive Kidneys and bladder system Ovaries and testes EXTERNAL ANATOMY  Head  Facial region (anterior) External nares Eyes Ears (flexible external fold: pinna)  Cranial region (posterior)  Neck – with jugular veins  Trunk  Thorax (anterior): chest  Supported by ribs  Abdomen (posterior): teats  Pectoral limb: shoulder girdle, arm, forearm, elbow, cannon, digits  Pelvic limb: pelvic girdle, thigh, knee, leg, hock, cannon, digits … external anatomy  Tail  Perineum : anal & urogenital opening  Ungulates – slender running type of legs  Odd toed ; 3rd toe is dominant; ex-horse  Even toed; equally developed 3rd & 4th toes (cloven hoof) Others: dew claw, dewlap, point of hock, pin bone, brisket External anatomy of birds  Body form & skin  Well developed head  Long, flexible neck  Shorter & plumper trunk  Tail reduced to a stump (uropygium)  Covered with feathers  Feathers  Flight feathers: large, stout; covers wing and tail  Coverts: smaller; covers base of wings, tail & body  Filoplumes (hair feathers) Filoplumes…  Feather follicle : deep pits where feathers are attached  Pterylae: paired areas with feathers  Apterylae: without feathers  head:  Beak  Cere  External nares  Eyes  Ears  Earlobes  Wattle  comb  Trunk : firm & flexible due to fusion of bones at the back  Keel (breast bone)  Wing (anterior pair of limb) Upper arm (bigger) Forearm (longer than upper) Carpus & metacarpus fused Only 3 digits  Hind limbs (tarsus, metatarsus; 4 digits)  Tail : with half circle of flight feathers (rectrices)  Under the base: cloaca  In front of the base: uropygial gland (oil or preen gland) Two cavities of the Animal body I. Dorsal cavity – contains the brain and spinal cord II. Ventral cavity – contains the visceral organs - divided into two parts by the diaphragm a. thoracic cavity – contain the heart and lungs b. abdomino pelvic cavity – 1. abdominal – visceral organs; stomach, intestine, liver, kidney 2. pelvic – contains the rectum, urogenital system SKELETAL SYTEM  Study of bones  Highly specialized supportive tissue characterized by its rigidity and hardness … functions  Provide mechanical support  Permit locomotion  Provide protection  Act as metabolic reservoir of minerals Osteogenesis  The process by which bone is  Endochondral ossification: formed thru the secretory activity bones that develop from of osteoblasts pre-existing cartilage  In embryo, occurs in 2 ways:  Examples: femur,  Intramembranous ossification : humerus bones develop in pre-existing  Responsible for the mesenchymal connective tissue longitudinal growth of ( membrane bones) bones Epiphyseal plate/line  Site of bone growth  Composed of different zones:  Zone of growth  Zone of cartilage transformation  Zone of ossification Classification of bones based on gross appearance  Long bones  Great dimension  Functions: as levers; for support; for locomotion  Ex: forelimb (humerus, radius, ulna…); hindlimb (femur, tibia…) …classification  Short bones  Cuboid or equal size  Function:absorbs concussion  Ex: carpals, tarsals … classification  Flat bones  Thin and expanded  Functions: protects vital organs (brain, lungs…); provides areas for muscle attachment …classification  Sesamoid bones  Sesame seed shape develops along the curse of tendons  Functions:reduce friction; change the course of tendons  Ex: patella empowher.com …classification  Irregular bones  Unpaired bones in median plane  Functions: for protection and support; for muscle attachment  Ex:vertebral column; some bones of the skull teachpe.com …classification  Pneumatic bones  With air spaces/sinuses that communicates w/ the exterior  Ex:flying birds; maxillary and frontal bones hsu.edu Division of skeleton  Axial skeleton  Includes all bone except those of the limbs or appendages  Composed of the skull, vertebrae and ribs  Appendicular skeleton  Made up of bones of the pectoral and pelvic limbs NERVOUS SYSTEM  Controls the body activities of the body  Muscular contraction  Secretions of endocrine glands  Heart rate  Respiration rate  Gastrointestinal motility  Rapid reflex action  Composed of brain, spinal cord and nerves Central Nervous System (CNS) Peripheral Nervous System (PNS) Central Nervous System  Containsthe majority of the nervous system and consists of the brain and spinal cord Brain – lies in the cavity of the cranium a. Cerebrum – largest part, separated in two halves by a deep groove - associated with intelligence and generally more developed in higher animals - right side of the cerebrum controls the left side of the body and vice versa - connected to its underside is the pituitary b. Cerebellum – much smaller than cerebrum - controls complicated movements c. Mid-brain and Medulla Oblongata – lies below and behind the cerebellum - controls the centers for respiration, heart regulation, control blood supply, heat regulation, and control of digestive system - 9 out of 12 important cranial nerves arise from the medulla ❖ The 12 cranial nerves 1. Olfactory - to the nose (smell) 2. Optic - to the eye (sight) 3. Oculomotor - to the muscles of the eye 4. Trochlear - to the muscles of the eye 5. Trigeminal - to the skin of the face 6. Abducent - to the muscles of the eye 7. Facial - to the muscles of the face 8. Auditory - to the ear (hearing) 9. Glossopharyngeal - to the tongue (taste) 10. Vagus - to the heart, larynx, lungs, and stomach 11. Accessory spinal - to the muscles of the neck 12. Hypoglossal - to the muscles of the tongue Spinal cord – continuation of the medulla oblongata down to the tail in the vertebral canal - the main trunk for communication with the brain Meninges – covers the brain and spinal cord Three membranes comprising the meninges include 1. Dura mater 2. Arachnoid 3. Pia mater Peripheral Nervous System  Resides or extends outside the limbs and organs  Not protected by bone, leaving it exposed to toxins and mechanical injuries  Divided into :  Somatic ns : innervates striated or skeletal muscles; bring quick adjustments to environmental changes  Autonomic ns : innervates glands and visceral musculature Divisions of Autonomic NS  Sympathetic NS  Aids in the control of most of the internal organs; works to mobilize the body’s resources for action under stress  Parasympathetic NS  Works to promote maintenance of the body at rest … nervous system  Nerve cells or neurons: maybe classified according to the direction of impulse conduction> - Afferent (sensory)- from effector organs to spinal cord/brain - Efferent (motor) – from spinal cord/brain to effector organs - Interneuron – from the afferent neuron within the CNS