GIT - Equine Flashcards
Are horses ruminants or non-ruminants?
Non-ruminant herbivores (they have one stomach)
Why has their digestive system evolved?
To digest a high fibre, low starch diet
What are the 2 sections of the horse digestive system?
- Similar to pre-ceacal digestive system of a mono-gastric
2. Similar to the rumen in a cow
What is included in the foregut?
Mouth/teeth
Oesophagus
Stomach
Small Intestine
What is included in the hindgut?
Caecum
Large intestine
Rectum
Anus
What are the functions of the digestive system?
Mechanically and chemically digest food,
Allow the absorption of food,
Assist the elimination of solid waste
What are the 2 main functions of the mouth?
Chew
Wet food with saliva
What is the function of the molars?
They grind food and mix it with saliva in preparation for swallowing
What is mastication?
Lateral and vertical movement of the jaw
How many chews does it take for a kg of fibrous roughage?
4,000 chews per kg
How long does it take to chew 1kg hay, 1kg oats?
hay - 40mins
oats - 10mins
What are the functions of saliva?
Lubricate food, buffer acidity of stomach, no digestive enzyme activity
When is saliva produces?
Only when chewing, horses do not produce saliva in anticipation for food.
What is the role of the stomach?
Transport food from the mouth to the stomach
What is peristalsis?
A series of muscular contraction and relaxations that squeeze the food along
What is the name of the joint that connects the oesophagus to the stomach?
Cardiac Sphincter - it is a one way valve
What is the transit time of the stomach?
Between 20 minutes and 2-3 hours
What are the two main regions of the stomach?
Non-glandular region (top) Glandular region (bottom)
What is the function of the non-glandular region of stomach?
Holding area
What is the function of the glandular region of the stomach?
Food mixes with gastric juices (HCl and pepsin) in fundic region
What happens in the stomach?
Food is mixed with pepsin (enzyme utilised in the digestion of protein) and hydrochloric acid (which helps break down solid particles)
What is the main practical implication of the stomach?
Unable to hold large amounts of food due to inelastic properties of stomach wall
What are the three parts of the small intestine?
Duodenum, jejunum and ileum
What is digested in the small intestine?
Starches, sugars, proteins and fat/oils
What is absorbed in the small intestine?
Sugars, amino acids, fatty acids, minerals, trace elements and vitamin A,D and E
What is the function of the jejunum?
Main site of absorption
What is the function of the duodenum?
Mixing digesta and secretions
What makes small intestine good for absorption?
Increased surface area due to mucosal wall being folded, and villi.
What is the function of the pancreas?
Controls glucose metabolism (insulin).
Pancreatic juices neutralise acidic material flowing from duodenum.
What increases the surface area of the small intestine?
Folds in the mucosa
Villi
Microvilli
What is the function of the large intestine?
Responsible for fibre digestion (starch and sugar snot broken down in SI)
Absorbs water, minerals, volatile fatty acids & B vitamins
What does large intestine consist of?
Caecum
Colon
Rectum
How big is the Caecum?
Approx. 1m length and can hold 25-30litres
What is the main function of caecum?
Break down plant material, can also digest soluble carbohydrates
What happens in the colon?
Water and electrolytes are absorbed
What are three Volatile Fatty Acids?
Acetic, Propionic and Butyric
What are functions of bacteria?
Ferment only one type of food. Grain fed horses have less efficient bacteria compared to hay fed
