Lecture 7 - Feeding IV Flashcards
What is the food quality of vegetation?
Low food quality
Low assimilation
efficiency
How do herbivores get past the cell wall of plants?
Complex dentition
What are the enlarged regions in a herbivores gut for?
Enlarge region of gut for symbiotic relationship
with bacteria
Bacteria hydrolyse cellulose
Mammals digest bacterial products
What are the Herbivore digestive strategies?
Foregut fermenters e.g. cows, sheep
Hindgut fermenters e.g. horses, rabbits
Where do hindgut fermenters derive energy?
fermenters
Where do Foregut fermenters derive energy?
Derive most energy from microbial
fermentation of cell wall
What is ruminating?
Regurgitating and rechewing food
Where does fermentation occur in foregut fermenters?
Microbial fermentation occurs in the forestomach
What is the rate limiting step in Foregut fermenters?
Foregut-midgut junction is rate-limiting
step – only small particles pass through
WHy might foregut fermenters be considered detritivores?
only eat food after it has been decayed by bacteria
What is the advantage of foregut fermentation?
Efficient at obtaining energy from
plant material
What is the purpose of restricting food passage through the gut?
Restricted passage of food through gut
Prolong retention
Increase extent of fermentation
What conditions must food fulfil to be useible for foregut fermenters?
Relatively low in fibre (higher quality)
Relatively high in protein
What problems when food is too low for foregut fermenters?
Not enough protein and Too much fibre means – cannot pass to midgut
What problems when food is too high for foregut fermenters?
Too much protein causes Excess gas production can lead to death by bloat
Where does Microbial fermentation occurs in small hindgut fermenters
Caecum
Where does Microbial fermentation occurs in large hindgut fermenters
Colon
What is Caecotrophy? Why is it done?
Ingest faeces to obtain protein from
bacteria
What happens to large particles in caecum fermenters?
Large particles expelled
What happens to small particles in caecum fermenters?
Small particles selectively retained
What advantage doe hindgut fermentation have over foregut fermentation for large animals?
Passage of food is unrestricted means more lower quality food can be eaten
What are the key characteristics of Hindgut fermenters?
Invest in digestion of cell contents Less efficient at extracting energy Consume large quantities of food Can detoxify food before it gets to bacteria Fewer restrictions on food quality
What food preparation is done by dentition?
Release cell contents
Facilitate fermentation of cell wall
Why is it Important to reduce size of food particles?
Increase rate and extent of fermentation and
digestion
What are the dentition features and purposes of foregut fermenters?
Shorter tooth row as can Rechew partly softened material while resting
Bacteria assist
What are the dentition features and purposes of Hindgut fermenters?
Longer tooth row as Only get one chance.
Must rupture many cells to release contents
what food characteristics do browsers usually deal with?
Relatively good quality
Patchy distribution or difficult to access
Chemical deterrents
Browsers typical features?
Low crown teeth
Selective feeders
Solitary
Grazers typical features?
High crown, continually growing teeth
Lawn mowers
Social
what food characteristics do Grazers usually deal with?
Relatively poor quality
Abundant
Very abrasive
What does allometric scaling mean for metabolism?
Smaller animals have higher metabolic
requirements
What doe the higher metabolic requirements mean for feeding habits?
Require high quality food
Must be selective
What food types are available to smaller animals
Invertebrates
Nectar/pollen
What food requirements do large animals have?
Require large quantities of food
What adaptations do large have to allow them to eat large quantities of food?
Hindgut fermenters (elephant)
-Complex guts
-Complex teeth
Filter feeders (blue whale)
-Simple guts
-Baleen filter
