ANS 002 Midterm 2

terrible...terrible.....terrible....

how many gallons is the rumen of the cow?

50 gallons

texture of rumen

papillae/furry

texture of reticulum

honeycomb

texture of omasum

deep folds for extra space

texture of abomasum

thin and sinuous

rugae

wrinkles in monogastric stomach/abomasum

gastric pit mucous neck cells

secrete mucous in stomach/abomasum

parietal cells

secrete HCL in stomach/abomasum

chief cells

secrete digestive enzymes (pepsinogen, rennin, gastric lipase)

the monogastric stomach is most like which portion of the ruminant stomach

abomasum

gallbladder

secretes bile for lipid absorption

pancreas

secretes digestive enzymes such as trypsin, chymotrypsin, carboxypeptidase, lipase, amylase

small intestine digestive facilitation

muscle contractions

serosa

outermost, protective layer of small intestine

muscularis externa

thicker muscle of small intestine wall responsible for peristalsis

peristalsis

contractions of muscles responsible for movement of food through digestive tract

submucosa

thick connective tissue in wall of small intestine with nerves, blood vessels, lymphatics

mucosa

innermost layer of small intestine with epithelium, lamina, muscularis mucosae

intestinal mucosa

circular folds for increased surface area

villi

structures that increase absorption through direct transfer of nutrients to blood stream and increased surface area

goblet cells

mucous cells in epithelium of digestive tracts

mesentery

holds intestines together and to wall of body (connective)

paracellular route

transport of molecules and nutrients across tight junctions BETWEEN epithelial cells

transcellular route

transport of molecules and nutrients into and out of plasma membrane of epithelial cells

can water be transported by both routes?

yes

large intestine

location of absorption of nutrients and water

villi location

within the lining of the small intestine

enterocytes

line villi and uptake nutrients

mechanical, chemical, enzymatic

three layers of digestion

duodenum

neutralize stomach acid and enzymatic digestion

jejunum

digestion and absorption

ileum

absorption

colon

part of large intestine that absorbs water and forms feces

cecum

blind pouch of large intestine, site of fermentation in hindgut fermenters

rectum

colon to anus connection

salivary glands

produce saliva (water, electrolytes, mucus, enzymes)

spiral intestine

structure only found in fish like sturgeon

classes of nutrients

water, carbohydrates, fats, proteins, minerals, vitamins

essential nutrients

must be obtained thru diet

nonessential nutrients

can be synthesized in the animal

energy nutrients

carbs, fats, proteins

structure nutrients

fats, proteins, minerals, water

regulatory nutrients

vitamins, water, minerals, protein

carbohydrates

-contain C, H, O
-ready source of energy (glucose)

carbohydrate examples

grains and forage

fats (lipids)

• C, H, O, but less O than carbs

• primarily triglycerides composed of glycerol and three fatty acids

• 2.25 more energy than carbs

triglycerides

primary form of stored energy in body and in dietary fats

proteins

• polymers of amino acid joined thru peptide bonds

• contain C, H, O, and N

aa

simple protein

aa + other substances

complex protein

minerals

inorganic elements (macro or micro)

vitamins

chemically unrelated organic compounds

fat soluble vitamins

A, D, E, K

water soluble vitamins

C, B, niacin, folic acid

proximate analysis

used to approximate the value of feed by separating feed components into groups

absorption of nutrients

transport into enterocytes (intestinal epithelial cells)

passive transport

• diffusion across membrane

• concentration gradient

• facilitated diffusion

• through transmembrane proteins

active transport

• requires expenditure of energy

• use of transporter proteins

nutrients transported thru active or facilitated transport

• carbohydrates (active and facilitated)

• amino acids (active and facilitated)

• minerals (co transported)

nutrients transported thru passive transport/diffusion

• fats (only free fatty acids and monoglycerides)

• vitamins (vitamin d stimulates active transport of Ca)

• water (osmosis)

energy use flow

body maintenance > repro > lactation > storage

TDN Total digestible nutrients

energy (E) value of feed

DE digestible energy

DE = gross E in feed - E in feces

ME metabolizable energy

ME = DE - E in urine and gaseous products of digestion

NE net energy

NE = ME - E used in consumption, digestion, metabolism of feed

maintenance energy use

• basal metabolism

• voluntary activity

• temp regulation

• minimum energy needed to sustain animal

production energy use

• reproduction

• growth

• lactation

• fat deposition

proximate analysis 7 measurable components

• dry matter DM

• crude protein CP

• crude fat EE (ether extract)

• crude fiber CF

• acid detergent fiber (ADF)

• neutral detergent fiber (NDF)

• ash

• nitrogen free extract NFE

DM definition

a feed’s nutritional value based on the weight after dehydration

CP definition

measurement of nitrogen in feed

• no indication of digestibility of protein

• 16% nitrogen, protein content can be found by multiplying nitrogen content by 6.25

EE definition/crude fat

portion of feed that is soluble in ether

CF definition

measurement of amount of cellulose and hemicellulose in simulated digestion

ADF definition

cell wall portions of forage that are made of up cellulose and lignin

ADF increase

digestibility decrease

NDF defintion

total cell wall comprised of ADF fraction plus hemicellulose

NDF increase

dry matter intake decrease

ash definition

the mineral content (metallic oxides or contaminates like rock or soil) after burning the feed

NFE definition and equation to find

fraction of feed primarily composed of readily available carbs

• measured by difference

• % NFE = 100 - (%water +%CP +%EE +%CF +%ash)

microbiota

collection of microorganisms

• eukaryotes, archaea, bacteria, viruses

amplicon sequencing

can identify bacteria by sequencing one region of gene

number of bacteria in gut

~500 to 1000 species

• 1-3 percent of body mass

anaerobic organisms

live in lower GI tract

aerobic organisms

live in upper GI tract

functions of microbes

protective, metabolic, structural/histological

rumen bacteria

make VFAs and protein through microbial growth

• polysaccharides → simple sugars

• cellulose → glucose through cellulase

VFAs

short chain fatty acids that are the end product of microbes using glucose as an energy source

• energy source for cow

• acetate

• propionate

• butyrate

propionate fate

converted to glucose in liver

acetate and butyrate fate

used for energy

• muscle synthesis

• adipose/fat synthesis

• mammary gland fat and lactose synthesis

pH>6 favors which digesters

fiber digesters (cellulolytic bacteria)

pH<6 favors which digesters

starch digesters (amylolytic bactera)

ph<5 in rumen

depresses protozoa

main form of fat in animals diet

triglycerides

protozoa in rumen

large ciliates, 50% of microbial biomass, digest starch and plant cell walsl

fungi in rumen

fiber digestion, physically break down plant tissues

archaea

methanogens that convert H and CO2 from fermentation in CH4 (methane)

methanogen

produce methane as a byproduct of energy metabolism. NOT BAD FOR COW

self v non self

immune system recognizable or unrecognizable molecules, making them self or foreign

antigen

generates antibodies

epitope

a facet of an antigen/portion of molecule connected to or recognized by immune system

primary lymphoid organs

lymphocyte development

• t cell maturation in thymus

• B cell maturation in bone marrow