IVS and AST Chapter 5 Respiratory System Unit 5 IVS and AST Chapter 5 Respiratory System

The Respiratory System Function Respiratory system + circulatory system =supply body with oxygen and rid body of carbon dioxide. Structures Nostrils (used to take in air) open into the nasal cavity which divides into many scroll-like sheets of bone.

The Respiratory Tract Covered in mucous, filters incoming air Nostrils and upper airways: Covered in mucous, filters incoming air Example: dust/dirt become trapped in the mucus, mucus accumulates and is eventually swallowed Trapped particles cause irritation, causes sneezing (reflex action) Warms cold air and adds moisture before it enters lungs Protection for the airways Olefactory receptors: detect smell

Pharynx Where the respiratory and digestive systems meet Food and air travel thru the pharynx Swallowing and breathing take place

Epiglottis Flap of tissue that covers larynx so food does not enter the trachea (windpipe).

Larynx Firm cartilage structure at the opening to the major airways Contains vocal folds- structures that allow vocalization

Trachea Larynx leads to the trachea Series of cartilage rings joined by connective tissues Rings are C shaped Lined with smooth epithelium that has surface cilia

Bronchi The trachea enters the chest about the region of the heart then branches into two bronchi Two bronchi - each leads to a lung Major bronchi divide into smaller bronchi to form bronchioles

Alveoli Air exchange happens here O2 exchanged with CO2 in the capillaries

The Respiratory Tract Lungs appear spongy with entrapped air Pleura- covers the lungs, small amount of fluid is present in the space to provide lubrication as lungs come close to chest wall

The Respiratory Tract Surfactant- produced in the lungs to keep the alveoli from collapsing, makes it easier for them to inflate Premature animals may lack surfactant

Respiration The act of inhalation & exhalation creating a breath Two Step process: 1. Inspiration (inhalation)- air is taken into lungs 2. Expiration (exhalation)- air is forced out

Mechanisms of Breathing Exhalation Intercostal muscles relax, ribs lower Diaphragm relaxes- arches towards the chest Drives the air out

Mechanisms of Breathing Involuntary process Occurs without thought But can be consciously controlled We think of this more as humans

Clinical Practice Cyanosis- tissues appear bluish, indication of inadequate oxygen being delivered to the tissues

Clinical Practice Pneumonia- inflammation or infection of the lungs usually caused by infection which leads to fluid (pus, mucous or other fluid) build up in the air sacs, oxygen cannot get to the blood. Can be bacterial or viral

Kennel Cough (Bordetella) Occurs in the respiratory tract of animals Severe/Chronic cough mostly in dogs Vaccines typically used with a nasal vaccine important to frequently vaccinate dogs that are kenneled and active with other dogs

Shipping Fever Occurs in livestock (horses, cattle) which are transported Causes a respiratory infection, affecting lungs and chest cavity Symptoms: fever, nasal discharge, coughing Treatment: antibiotics and proper sanitation, vaccines available prior to transportation

Diaphragmatic Hernia Diaphragm condition Muscle in chest tears and organs can pass through Lungs can’t expand fully and labored and difficult breathing occurs Common in trauma, HBC Surgical correction needed

Heaves Allergic respiratory condition in horses; lifelong condition Common term for COPD (chronic obstructive pulmonary disease) Symptoms: coughing, nasal discharge, labored breathing, tire easily

Roaring Condition in horses when larynx opens only a small amount due to trauma of the nerves Causes a sound like roaring Surgical correction

Heartworms Spread by mosquitoes Affect the heart and lungs http://www.heartwormsociety.org/pet-owner-resources/heartworm.html Can be fatal

Review: The Flow of Air Nostrils= Pharynx= Larynx= Trachea= Bronchi= Bronchioles= Alveoli=