This document provides an overview of the major organ systems in animals, including their structures and functions. It discusses the skeletal, muscular, nervous, circulatory, respiratory, excretory, digestive, endocrine, integumentary, and reproductive systems. Each system is comprised of various tissues and organs that work together to carry out important life processes like movement, nutrient transport, waste removal, and reproduction. Understanding animal anatomy and physiology is important for efficient livestock production and ensuring animal wellbeing.

1. Animal Organ Systems
Anatomy and Physiology

2. Fundamentals of Life
 All living things are made up of cells.
 Cells are the most basic structure of life.
 Cells need oxygen, food/energy, and
water to survive.

3. Natural Hierarchy
 Cells are the most basic and simple.
 Cells that are all alike work together to form
tissues which perform tasks.
 Tissues that are alike work together to form
organs which complete jobs.
 Organs work together in organ systems to
carry out processes.
 Organ systems work together to support the
life of an organism.

4. How do we study animals?
 We look at the outside of them – the
outer physical structures.
 We look inside of dead animals – the
internal physical structures.
 We look at the tissues under a
microscope – microscopic structures.
 We study the chemical reactions
between cells, tissues, and organs.

5. Anatomy
 The study of the form, shape, and
appearance of an animal – its structures
both internal and external.
 Gross anatomy is the study of the
structures – internal and external – that we
can see with the naked eye.
 Microscopic anatomy is the structures that
can only be seen under magnification

6. Physiology
 The study of the functions of the cells,
tissues, and organs of the animal.
 Biochemistry
 How cells, tissues and organs work
together to complete a task…digestion.

7. Why study anatomy and physiology?
 Efficient production of livestock requires
understanding the anatomy and
physiology related to Production.
 Production is muscle gain, milk or egg production,
and hair or wool production.
 Raising animals requires an
understanding of the requires needed for
animal wellbeing.
 Animal wellbeing is caring for animals so that their
basic needs are met and they do not suffer.

8. Mammals vs Non-mammals
 Most of our livestock are mammals.
 i.e. – vertebrate that has hair, gives birth to
live young, produces milk, & maintains
constant body temperature.
 Cattle, horses, pigs, goats & sheep, etc.
 Exceptions are poultry & aquacrops.
 Poultry – birds – ducks, chickens, turkeys, etc.
 Aquacrops – fish, shrimp, etc.

9. Organ Systems
 Skeletal
 Muscular
 Nervous
 Circulatory
 Respiratory
 Excretory
 Digestive
 Endocrine
 Integumentary
 Reproductive

10. Skeletal
 Bones
 50% water, 26% minerals (Ca & P),
20% protein, 4% fat
 Core is soft and spongy – called marrow
 Marrow makes new red blood cells for body.
 Cartilage
 Soft, tough tissue found between bones
that cushions joints
 Ligaments
 Long stretchy tissue that holds joints
together

11. Skeletal
 Gives structure and support
 Protects internal organs
 Makes locomotion/movement possible

18. Muscular
 Muscles
 Fibrous cells that are design to contract and relax in
pairs
 Voluntary – under the organisms conscious control –
triceps
 Involuntary – automatically move to regulate body
functions – heart and diaphragm
 Tendons
 Long, thin, stretchy tissues that attach muscles to
bones.
 Muscles pull against bone when they contract which
causes movement.

19. Muscular
 Primary function is movement.
 External & internal
 Also protect delicate organs
 Muscles make up about half our
livestock animals’ weight.
 Muscles are the meat of the animal.
 Composed mostly of protien.

21. A=Rhomboideus capitis
B=Splenius
C=Levator scapulae ventralis
D=Supraspinatus
E=Infraspinatus
F=Teres major
G=Serratus dorsalis
H=Longissimus dorsi
I=Multifidae spinae
J=Clavotrapezius
K=Clavobrachialis
L=Acromiodeltoid
M=Spinodeltoid
N=Acromiotrapezius
O=Spinotrapezius
P=Spinalis dorsalis
Q=Latissimus dorsi
R=Rhomboideus

22. Nervous
 Brain
 Soft tissues that coordinates
all aspects of animal function
 Spinal Cord
 Main “highway” for nerve
impulses to travel from brain
to rest of body
 Nerves
 Branch out and reach rest of
body

23. Nervous
 Uses electrical impulses to send
messages from brain throughout body.
 Controls activity, learning, memory
 Central Nervous System and Peripheral
Nervous System

25. Circulatory
 Heart
 Technically a muscle
 Pumps blood with 4 chambers and 2 valves
 Arteries
 Carry oxygen rich blood from lungs and heart
to tissues
 Veins
 Carry blood back from tissues to lungs and
heart.

26. Circulatory
 Blood
 Plasma
 Liquid part of blood
 red blood cells
 Carries O2 and carbohydrates (glucose)
 white blood cells
 Fights pathogens
 Platelets
 Makes blood clot

27. Circulatory
 Also includes the Lymph Glands
 Secrete disease fighting materials
 Moves materials throughout the body

28. Respiratory
 Nose
 External opening of the body
 Pharynx & Larynx
 Pharynx connects the esophagus and trachea
 Larynx is the “voice box”
 Trachea
 Wind pipe that connects nasal passages with lungs
 Lungs
 “bags” that expand and contract to bring in fresh air
and expel old air

29. Respiratory
 Function is to bring oxygen
into the body and expel
carbon dioxide.
 Exchange of gasses
happens inside the lungs in
the alveoli.
 Lungs expand and contract
due to the movement of the
diaphragm.

30. Excretory
 Also referred to as the urinary system.
 Kidneys
 Remove waste materials from blood
 Bladder
 Holds liquid wastes - urine
 Ureters
 Connect bladder to urethra
 Urethra
 Empties urine to the exterior of the animal

31. Digestive
 Mouth, esophagus, stomach, small
intestine, cecum, large intestine, rectum,
anus
 Breaks down food into usable energy
 Removes unusable food from body

32. Endocrine
 Ductless glands in the body
 hypothalamus, pituitary, pancreas, liver,
thyroid, adrenal
 Secrete hormones that chemically
regulate certain functions of the body
 Play a large role in reproduction,
digestion, growth, etc.

33. Integumentary
 Skin, hair, hooves, horns, etc
 Keeps out pathogens, regulates body
temp, gives shape and color, protects
internal organs
 System made almost entirely out of protein
 Animal skin is called the hide
 Most animal hides made into leather

34. Reproductive System
 Most complex system in animals
 Allows for reproduction of animals and
the continuation of the species
 Different structures between male and
female
 Most animals fundamentally have the
same system, just varies in structure
between species.