Agriculture Reference
In-Depth Information
Waterfowl anatomy is slightly different. The gizzards of ducks and geese are far more
rigid and the ability of the birds to handle waterborne parasites and contaminations is
much greater. They also are able to handle the cold much better, due to their down feath-
ers and subcutaneous fat layer.
This chapter focuses on chickens, but serves as an overview of all poultry.
What's in a Bird?
Although all poultry species and most individual birds have unique physical character-
istics, distinctive mannerisms, and matchless temperaments, when you get right down
to it, poultry are made of cells. Cells can be divided into two types: the tiny
prokaryot-
ic cells
(simple cells) such as bacteria, and the larger
eukaryotic cells
(complex cells)
that have a
nucleus
(a central body where genetic information is stored) and
organelles
.
Think of organelles as miniature organs with specific functions within each cell, not un-
like those in our own body systems.
It is vital for the cells' health that all of the organelles function properly. It is therefore
crucial that the birds have a balanced diet. While some items in the diet are needed only
in minute quantities of less than 0.01 percent, they are still essential for healthy cell
function. Healthy cells lead to healthy tissues, organs, organ systems, and of course the
sum of it all, a healthy bird.
COMMERCIALLY RAISED BIRDS: SUPERSIZED AND
SICKLY
The large breast muscle in modern broiler chickens and modern commercial turkeys
has caused considerable change to the anatomical balance of the bird. Created by
agribusiness geneticists for rapid overgrowth, these bird types find natural breeding
very difficult and often impossible to accomplish. The large breast size also leads to
increased stress on the other systems of the body. Because these genetically forced,
physically distorted birds can't walk as easily as traditional fowl, the modern broiler
