Transcript Cud talk

MAMMALIAN NUTRITION
Part II. Specialization of
carnivores and herbivores
RICHARD LLOPIS-GARCIA
A2 BIOLOGY Adapted by MH
Learning Outcomes
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4. Compare the specialization of teeth in
herbivores and carnivores
5. Describe the specialized digestive
system of ruminants
Skulls and Teeth
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Quickly look at the herbivore and
carnivore skulls .
Compare the number, shape, and possible
function of each type of tooth
What differences can you identify?
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50% of organic carbon is contained in
cellulose.
Many animals lack cellulases
Some microorganisms secrete cellulases
which allow them to utilize dietary cellulose
and other plant wall materials.
Some animals have developed specialised
digestive systems which include ‘mutalistic
microorganisms’
This allows them to access nutrients and
cellulose from plant material
Digestive Anatomy in
Ruminants
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The stomach of ruminants has four
chambers:
Rumen,
Reticulum
Omasum
Abomasum
Collectively, these organs occupy
almost 3/4ths of the abdominal cavity,
Ruminants
The first two chambers :
 Rumen
 Reticulum
 Fermenter packed with microorganisims
 Thick muscular walls : churn with saliva
 pH maintained by buffers in the saliva
 Temp kept between 38-42 º C
A load of tripe
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The interior
surface of the
rumen forms
numerous
papillae that
vary in shape
and size.
More Tripe
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Reticular
epithelium
has a honeycombed
appearance.
Chewing the Cud
Ruminants:
‘Chewing the Cud’
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Balls of ‘cud’ is regurgitated from rumen to
the mouth for rechewing
‘Ruminating’ for hours
The partially digested cud and the
microorganisms pass into the ‘true
stomach’
Omasum
Abomasum
Digestion continues
Mutualistic Relationship
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Microbes use glucose from cellulose for
their own metabolism
This metabolic process produces waste
products:
CO2 (belching)
methane (belching)
fatty acids(short chains)
absorbed into blood via rumen wall
Sources of Protein
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Available from plant cells (as cell wall now
digested)
From cytoplasm of microorganisms
Microorganisms convert non- protein
nitrogen into proteins
Sources of protein
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Ammonia is a waste product produced by
the microorganisims
Absorbed through rumen to
Transported to liver via blood
Converted to urea : excreted in urine
Some urea is transported and secreted to
salivary glands
Microorganisms can convert non protein
nitrogen into protein
Other mutualistic relationships
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Many termites large numbers of protozoa
in their hind gut
Protozoa break down cellulose to glucose
Protozoa use glucose but produce fatty
acids as a waste product
Other mutalistic relationships
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Rabbits have a branch of large intestine
called the Caecum
This contains microorganisms and
empties into large intestines
Absorption of nutrients and
microorganisms is inefficient
Produce two kinds of faeces