August 2008 Development and Types of Immunity Kelly Paquin Cal Poly San Luis Obispo AGED 410 Modified by Georgia Agricultural Education Curriculum Office July, 2002

August 2008 The healthy body against a world of disease The body has two “lines” of defense against disease organisms

August 2008 The first line of defense includes : SKIN - which is covered by hair, feathers, etc., and is thick and able to sweat in some species (others must pant) MUCOUS MEMBRANES - which are the sticky, protective coating that trap pathogens from further penetration (ex: in the nose and the tearing that washes pathogens out of the eyes)

August 2008 GUT - which is difficult for pathogens to pass through because of acids produced by digestive processes CELL WALL - which is often mucus coated and may have cilia to protect the cell COUGHING - which rids the body of disease organisms which may have been swallowed and the mucus they may be trapped in FLUSHING EFFECT OF URINATION - which washes pathogens out

August 2008 The second line of defense includes: WHITE BLOOD CELLS - which are produced by the body to help fight infection LYMPHATIC SYSTEM - which filters pathogens and other undesirables out of the body’s lymphatic system LIVER - which filters blood and detoxifies poisons ANTIBODIES - which are substances produced by the body to fight off pathogens

August 2008 Once pathogens have breached the body’s line of defense, they generally multiply and attach, destroying body tissues. Disease activity results in changes in the tissues that are invaded.

August 2008 Typical signs of infections are: Redness due to increased blood flow to the injured area Swelling Localized heat in the area of the injury increased body temperature Pain resulting from excessive pressure on tissues due to swelling

August 2008 The speed at which a disease attacks and animal is termed: ACUTE - relatively sudden appearance of symptoms (within 24 hours) CHRONIC - that which develops more slowly, lingers, and will frequently reappear

August 2008 The conditions could to make an animal become ill are: OVERWORK EXPOSURE to: –cold –heat –rain –snow –sun –humidity –other animals –parasites LONG SHIPMENTS WEANING INJURY MANAGEMENT PRACTICES ACCESS TO STAGNANT WATER SPOILED FEEDS POISONOUS PLANTS

August 2008 Diseases can be spread by: DIRECT CONTACT - animals rubbing against each other (ringworm), sexual contact (venereal infections), or by mucus (respiratory diseases) CONTACT WITH NON-LIVING OBJECTS - fence posts, trucks, feeders, needles, etc. INFECTION FROM SOIL - tetanus, blackleg INFECTION FROM FOOD OR WATER - influenza (viral infections)

August 2008 AIRBORNE INFECTION - coughing and sneezing of infected animals on each other INFECTION FROM BLOOD SUCKERS - such as flies and mosquitoes carrying such diseases as encephalitis INFECTIONS FROM ORGANISMS - normally in an animals body. However, they only become dangerous when the animal’s defenses are weakened by some health or stress-related problem

August 2008 Good management will do much to help animals resist disease: Be alert for signs of disease and conditions which can cause stress and strain Provide clean, disinfected quarters, free from draft Provide adequate ventilation an plenty of sunlight

August 2008 provide proper drainage of holding areas, barns, freestalls, etc. - to help maintain the dries area possible protect from excessive sun, wind, and rain, without over crowding practice rigid sanitation and manure removal procedures

August 2008 Provide a well balanced diet get accurate diagnosis of health problems IMMEDIATELY so that treatment can be provided avoid unnecessary stress and strain buy disease free stock from healthy herds and flocks

August 2008 Isolate new animals for a period of time - be sure that they are healthy before introducing them to your herd or flock follow a set vaccination program be cautious of visitors from other operations as they may carry disease pathogens on shoes and clothing dispose of dead animals immediately