Absorption of nutrients in animals for Animal nutrition 101

1. Animal Nutrition
Absorption of
Nutrients in
Animals
ANGELA LABRADOR

2. Objectives
 1- Describe the absorption of
nutrients in animals.

3. Absorption of Nutrients
 Absorption is the process of taking
nutrients from the digested feed into the
blood and lymph systems.
 In non-ruminants most absorption
takes place from the small intestine with
a lesser amount being absorbed from the
large intestine.
 In ruminants there is some absorption
of nutrients through the wall of the
rumen.

4. Absorption of Nutrients
 Villi are small cone-shaped projection on
the wall of the small intestine. Each villi
contains a network of blood capillaries
through which nutrients enter the blood
stream.
 Protein is converted to amino acids.
 Starches and sugars are converted to
glucose, fructose and galactose.
 Crude fiber is converted to short chained
fatty acids or glucose by digestion.
 These nutrients pass into the blood
capillaries by osmosis through the semi
permeable membranes.

5. Absorption of Nutrients
 The two methods of absorption are
diffusion and active transport.
 Diffusion is the movement of molecules
from an area of high concentration to one
of low concentration.
 Active transport is the movement of
molecules from one area to another
requiring the expenditure of energy.
 Amino acids and glucose move by
active transport.

6. Diffusion
 moves molecules down a
concentration gradient in a manner
that does not require the cell to
expend energy. Water, oxygen,
carbon dioxide, and a few other
small molecules diffuse directly
across the plasma membrane by
passing between phospholipid
molecules.

7. Passive transport
is accomplished by diffusion, the
spontaneous movement of a
substance from a region of greater
concentration to a region of lesser
concentration. The difference
between the concentration of a
substance in two different areas is
known as a concentration gradient.

8.  Substances that cannot pass directly
through the plasma membrane diffuse
into or out of cells with the aid of
hollow, channel-like proteins in a
process known as facilitated diffusion.
These channel proteins are shaped so
that only one substance, or a small
group of closely related substances,
can pass through each type of protein.
This specificity enables a cell to control
precisely the molecules that travel in
and out of the cell.

9.  In order to move substances
against a concentration
gradient—that is, from the side
of the plasma membrane where
the concentration of a
substance is lower to the side
where it is already higher—a
cell must expend energy in a
process known as active
transport

10.  Active transport is achieved
by membrane proteins
called pumps,
 which have a docking site that
is shaped to fit a specific
substance.

11.  These pumps are open on either the
inside or the outside of the cell. When
the proper molecule or ion attaches to
the docking site, the pump changes
shape so that the docking site moves
its opening to the other side of the
plasma membrane, releasing the
molecular cargo. Many pumps obtain
the energy necessary to perform this
work from adenosine triphosphate
(ATP), a molecule that serves as the
main energy currency of living cells.

12. Nutrient Transport
 Nutrients in the water soluble form, are
primarily carried by the blood in the
animals body from where they are
absorbed to where they are utilized.
 Nutrients are used for maintenance,
oxidation provides hear for body
temperature and movement.
 Nutrients are also used fro growth and
fattening, fetal development,
production of milk and eggs, wool and
mohair and work.

13. Metabolism
 Metabolism is the sum of the chemical
and physical changes continually
occurring in living organisms and cells
utilizing nutrients.
 Anabolism is the formation and repair of
body tissues.
 Catabolism is the breakdown of body
tissue into simpler substances.

14. Review Answers
 1.- Most absorption is done by
diffusion and active transport. Most
in the non-ruminant stomach is
done in the small intestine, in
ruminant animals they use the small
intestine and to a small degree
through the rumen.

15. Review Answers
 2.- Metabolism refers to the
chemical and physical changes
occurring after the feed nutrients
are absorbed into the bloodstream.

16. THANK YOU….