Animal Nutrition Flashcards
(94 cards)
Ingestion
is the process whereby food is taken into the mouth.
Digestion
is the process whereby food molecules are broken down into small particles
Two types of digestion
Mechanical digestion and Chemical digestion.
Absorption
is the process whereby the digested food is taken up by the blood streams
Assimilation
is the movement of food to different cells of the body.
Secretion
is the process whereby digestive juices are released by different organs of the body
Egestion/excretion
is the elimination of waste out of the body.
Examples of ruminant animals
➢ Cattle
➢ Sheep
➢ Goats
Examples of non-ruminant animals
➢ Fowl
➢ Pig
➢ Donkey
➢ Horses
Comparison of external structure of the alimentary canal of ruminants and non-ruminants
Ruminants:
➢ Polygastric
➢ Complex stomach
➢ Digest food with high quality fibre and cellulose
➢ Chew their food partially, regurgitate later and re-chew.
Non-ruminants
➢ Monogastric
➢ Simple stomach
➢ Cannot digest food with high quality fibre and cellulose
➢ Chew their food properly and swallow it once
Functions and adaptations of various structures of the alimentary canal
Alimentary canal(digestive tract or gut) :
is a long tube, divided into several regions which are specialised for; Ingestion, Digestion, Absorption and Egestion (Excretion/Elimination).
Mouth
Functions of the Mouth:
➢ Intake of food (ingestion)
➢ Grinding and chewing by teeth
➢ Secretion of saliva by salivary glands
➢ Moistening and softening by saliva
➢ Rolling, mixing and swallowing by tongue
Tongue
Functions of the tongue:
➢ rolls the food into bolus
➢ mixes the food with saliva
➢ It is a taste organ
Peristalsis
is the involuntary contraction and relaxation of muscles that pushes food through the alimentary canal
Functions of peristalsis
➢ Peristalsis occur in the oesophagus, stomach and intestines ➢ If the rate of peristalsis increases, food will move faster along the alimentary canal and less fluid will be absorbed leading to Diarrhoea
➢ If the rate of peristalsis decreases, food will move slower along the alimentary canal and more fluid will be absorbed leading to Constipation
Retro-peristalsis
Retro-peristalsis is the involuntary contraction and relaxation of muscles that pushes food back to the mouth in the alimentary canal
Pharynx
is the funnel-shaped muscular tube connecting the mouth cavity to the digestive and respiratory systems. It is enclosed by the epiglottis to prevent food from entering the trachea during swallowing.
Functions of the pharynx
➢ Exchange of gases
➢ Allows for the passage of food from the mouth to the oesophagus ➢ Connects the mouth to the oesophagus
Oesophagus (gullet)
There is no absorption of nutrients
Oesophagus is a tube-like structure that extends from the back of the throat (pharynx) to the stomach.
Functions of the oesophagus
➢ Connects the mouth to the stomach
➢ Allows the passage of food to the stomach
➢ Contain mucous membranes that secrete mucus which lubricates the food for easy passage.
Crop
There is no absorption of nutrients
is the enlarged extension of the oesophagus where food is stored, moistened and softened in fowls.
Functions of the crop
➢ Stores the food
➢ Moistens and softens the food
Stomach
Stomach is a pear-shaped, sac-like structure that store and chemically digest the food
Functions of the stomach (stomach of a pig)
Stores food temporarily
➢ Chemically digest the food
➢ Secretes mucus that protects it from acidity