Download Skin and Mucous Membranes

Skin and Mucous
Membranes
The tissues covering the body are the animal’s first line of
defence against infectious disease. Healthy skin is a physical
barrier to organisms inhabiting its surface and the
surrounding environment. Abrasions and open
wounds provide an opportunity for organisms to
penetrate the barrier, infect underlying tissues
DIGESTIVE SYSTEM
and enter the circulatory system. Hair
provides protection from abrasion and may
URINARY
RESPIRATORY
SYSTEM
prevent hazardous materials and insects from
SYSTEM
contacting the surface of the skin.
REPRODUCTIVE
SYSTEM
Mucous membranes line the inner surfaces of all organ
SKIN
MUCOUS MEMBRANES systems which are exposed to the environment, as shown in
the diagram on the left. These surfaces are normally inhabited
by native bacteria which, in the healthy animal, do not cause
disease. By competing with pathogenic (disease-causing)
bacteria, these native organisms provide some protection to
the animal.
In the digestive system, a large and diverse population of
beneficial bacteria (including rumen microbes) assist in the
digestion of feed and manufacture nutrients essential to the
animal (e.g. B-vitamins and vitamin K).
The mucous membranes lining the windpipe are composed of
cells having hair-like projections called cilia. These cilia move
in waves, carrying foreign material and bacteria away from the
lungs.
source: Dairy Production Primer - Herd Health Management
©2004 Western Dairy Science Inc.