unit 4 Flashcards
(57 cards)
what are the parts of the ruminant stomach and their functions?
rumen: fermentation chamber, 80%
omasum “manyplies” “butcher bible”: breaks down particles + absorbs water, 7-8%
abomasum “true stomach”: first gland, 8-9%
reticulum “honeycomb”: works w/ rumen, 5%
how is the rumen a feemantation chamber?
rumen is dark, aerobic, and has a 6-8 pH which gives bacteria an environment to deaminate bacteria and synthesize VFAs and vitamin k+b
what is digestion?
breaking down of food into nutrients- chemical, mechanical, microbial (most important in ruminants)
what is the cecum analagous to in the horse?
appendix
what are the lengths of a horse GI tract?
esophagus: 4-5 ft
stomach: 8-19 quarts (8%)
small intestine: 70 ft, 68 quarts (30%)
cecum: 4 feet, 28-36 quarts(15%)
large colon: 10-12 ft, 86 quarts (38%)
small colon: 10-12 ft, 16 quarts (9%)
what are digestive problems in horses?
colic “twisted gut”: small intestine gets twisted around
founder: too many readily digestabile nutrients which declines the coffin bone
what are passage rates and what affects it?
how long it takes for food to be ingested then excreted
monogastrics: 8-12 hours
ruminants: 96-120 hours
stress and food digestability: higher quality is faster
what are the differences in the mouths of ruminants and monogastrics?
both: water (moistens feed), mucin (lubrication), bicarbonate salts (buffer for pH)
monigastrics: salivary amylase- breaks down sugars to provide energy
ruminants: no enzymes
what are VFAs and the different types?
main energy source for ruminants- absorbed through the rumen
-propionate: high in grain fed animals, white fat
-acetate: high in grass fed animals, yellow fat
what is eructation?
belching of co2 and methane (produced by microbial fermentation) in ruminants- gas is at the top of rumen
what is the urea cycle?
it preserves nitrogen in the ruminant system by taking the amine group from anino acids and forming new ones
-amino acids become ATP, co2, and ammonia to form new ones
what is urea?
nitrogen molecule with a crude protein of 281%
what is the esophageal groove?
a groove in young ruminants to transport milk to abomasum instead of rumen (begins functioning at 60 days)
becomes nonfunctional once diet changes
what are the parts of the horse stomach?
glandular: active region with digestive juices
nonglandular
divided by margo pilatus
what are characteristics of the monogastric stomach?
pH is 2-3
glands that produce digestive juices: gastin, HCl, pepsin, rennin
what is gastrin?
released by: stomach distension and proteins
inhibited by: HCl and stomastatin
-releases digestive enzymes to begin digestion process
what is HCl?
released by: parietal cells
-activates pepsin
what is pepsin?
released by: chief cells
-begins protein digestion
what is rennin?
enzyme to digest mothers milk, also used in cheese making
what is in the liver?
bile salts: activates lipase to break down fat, neutralizes chyme, produces cholesterol
what are the parts of the small intestine?
duodenum, jejunum, ileum
what does the duodenum do?
-houses brunners gland: secretes alkaline mucus to buffer chyme by raising pH
-recieves secretions from the liver (then stored in gall, NA to horse)
what enzymes are secreted by the duodenum? (and their respected substrates)
-peptidase: peptide (protein)
-lactase: lactose (sugar)
-sucrase: sucrose (sugar)
-maltase: maltose (sugar)
-chymotrypsin: protein
-trypsin: protein
-lipase: triglycerides (lipid)
-amylase: carbs/starches
what dies the jejunum do?
absorb nutrients with villi
