Anatomy of Livestock Species Flashcards
How is digestion achieved?
A combination of Physical/Mechanical, Chemical, Enzymatic, and Microbial actions.
What are the digestive system types?
Monogastric and Ruminant
What types of animals are monogastric?
Swine and Equine
What types of animals are ruminants?
Cattle, sheep, goats
What makes horses special when it comes to being monogastric?
they are monogastric herbivores, or non-ruminant herbivores
How many stomachs does a ruminant have?
1, but that stomach has 4 compartments
What are the 4 different compartments of the ruminant stomach?
Rumen, Reticulum, Omasum, and Abomasum
Which type of digestion is the fastest, and why?
Monogastric, different feeds have different digestibilities, and rumination takes a lot of time.
What are the functions of the mouth?
take in food, taste, chew, and mix the food with saliva
What is mastication?
the physical reduction of feed to increase surface area
What are the adaptations related to mastication?
Carnivores have incisors made for tearing and little chewing, herbivores have specialized molars made for chewing and grinding, horses grind in a circular motion with their molars, sheep and cattle have dental pads and molars on the bottom, molars roll and crush turgid and brittle food.
What are the three pairs of salivary glands?
Parotid - contains secretory proteins and produces zymogen, located in front of ears.
Submaxillary - produces seromucous fraction, located inside lower jaw.
Sublingual - contains mucous secretory portions, located underneath the tongue.
serous gland secretions are sometimes rich in What?
proteins and water
Mucous gland secretions are sometimes rich in what?
glycoproteins and water
Saliva is made up of what?
99% water
and 1% mucin, inorganic salts, alphaamalayse, and alysazyme
Which animals lack amalyse?
horses, cats, and dogs
Which animal has amalyse with low activity?
Pigs
What do salivary glands secrete?
water, mucin, bicarbonate salts, and amalyase
Water
moistens the feed and aids in mechanisms
Mucin
lubrication aid for swallowing
Bicarbonate salts (sodium bicarbonate)
act as a buffer to regulate stomach pH
Amylase
the digestive enzyme that starts to break down simple sugars in the feed
Swine differ from ruminants in that…
they secrete salivary amylase while cows do not secrete enzymes, but provide a source of N,P, and K
Esophagus
A muscular tube that connects the mouth and stomach, and uses peristaltic waves to move ingested material
horses esophagus
have one-way peristaltic waves, a very strong sphincter, and the tube connects at an oblique angle, so regurgitation is nearly impossible
Ruminants esophagus
two-way movement that allows rumination to occur easily, so regurgitation is very easy
Cardia
the sphincter at the junction of the esophagus and stomach, which controls the passage of ingesta into or out of the stomach
Esophageal region
non-glandular area surrounding the cardia
Cardiac gland region
(1/3 of stomachs surface) contains cells that produce primarily viscous mucous that protects the stomach lining against acid
fundic gland region
contains cells that protect the gastric secretions need for the initial stages of digestion
Parietal cells in fundic gland
produce hydrochloric acid
chief cells in fundic gland
produce enzymes/precursors of enzymes and controls the passage of food from the stomach to the small intestine
Pyloric gland region
located before the entrance to the small intestine, contains cells that produce mucous and some proteolytic enzymes
Plyorous
the sphincter at the beginning of the small intestine which controls the passage of chyme out of the stomach
The monogastric stomach
A hollow, pear-shaped, muscular digestion organ that stores ingested food and is very acidic with a pH of around 2 or 3. Muscular movements cause a physical breakdown, secretes juices, and regulates gastric secretions.
What are the digestive juices of the monogastric stomach?
Gastrin, Hydrochloric acid, Pepsinogen, Rennin (chymosin), and mucous.