ANSC Exam 2
Terms in this set (150)
Lips (Non Rum)
First part of tract, imp for horses (prehensile), not imp for chickens (don't have them)
Tongue (Non Rum)
Move food in mouth, prepare for swallowing
All physical and chemical changes food undergoes in order to be absorbed
Teeth (Non rum)
Chewing food for particle size reduction, or tearing in carnivores
Salivary Glands (Non rum)
Produce Saliva containing mucus and amylase
Salivary mucus function
moisten food/stick it together, lubricate
Salivary amylase function
Esophagus (non rum)
Connects mouth to stomach, moves food via peristalsis
Stomach (Non rum)
Chemical digestion of food begins, serves as storage place, produces HCl, Pepsinogen, Gastric Lipase, Mucin, Intrinsic Factor
Regions of Stomach (Non rum)
Esophageal, cardiac, pyloric, fundic
HCl Function in stomach (non rum)
contributes minimally to digestion, main function is activating pepsin
Pepsinogen Function in stomach (Non rum)
Inactive form that HCl activated to pepsin, digests proteins
Gastric Lipase Function (Non Rum)
digests fat, but not in stomach (fat isn't emulsified and pH not optimal)
Mucin function in stomach (non rum)
Protects stomach lining
Intrinsic Factor function (non rum)
necessary for B12 absorption
Sections of the SI
Duodenum, Jejunum, Ileum
First section of SI, most glandular (location of other digestive secretions), active absorption
Middle SI section, continued absorption and digestion
Last SI section, continued digestion and absorption
Function of SI secretions (Non rum)
Finish digestion of intermediate molecules to simple molecules
SI Secretions (Non Rum)
Maltase, sucrase, lactase, aminopeptidases, mucleosidases, nucleotidases
Liver Function in Digestion
Bile Function in Digestion
Gall Bladder Function
Pancreas Location and Function
Lies along duodenum, produces secretions and hormones
Pancreas endocrine secretions
Insulin, Glucagon (endocrine)
Pancreas Exocrine Secretions
Bicarbonate, pancreatic amylase, pancreatic lipase, trypsin, chymotrypsin, carboxypeptidase
Pancreatic Bicarbonate Function
Buffers stomach acid, raising pH
Pancreatic Amylase function
Pancreatic Lipase function
Trypsin, Chymotrypsin, and Carboxypeptidase Functions
Roles of the LI
Storage and water absorption
Major GI Hormones
Gastrin, Gastric Inhibitory Polypeptide (GIP), Secretin, Cholecystokinin (CCK)
Gastrin Origin, Releasing Mechanism, and Function
Origin: Distal stomach near pylorus
Releasing mechanism: high stomach pH, stomach distension, protein in stomach
Function: Stimulation of acid secretion by gastric glands
Gastric Inhibitory Polypeptide (GIP) Origin, Releasing Mechanism, and Function
Origin: Duodenum, Jejunum
Releasing Mechanism: Fat and Carbs in duodenum
Function: Inhibition of gastric secretion and motility
Secretin Origin, Releasing Mechanism and Function
Releasing Mechanism: Acid in duodenum
Function: Stimulation of pancreatic Bicarbonate secretions
Cholecystokinin (CCK) Origin, Releasing Mechanism, and Function
Releasing Mechanism: Fat and proteins in duodenum
Function: stimulates enzyme secretion from pancreas, inhibits gastric emptying and causes gall bladder contraction
Enterocrinin Origin, Releasing Mechanism, and Function
Releasing Mechanism: Food digestion products
Function: Stimulation of SI
Esophagus in poultry
Includes widened area called crop, which stores food and allows for easy regurgitation
Poultry, corresponds to stomach of non-rum
Poultry, grinding function, very muscular and catches/accumulates grit
Poultry, common passage for digestive, urinary, and repro tracts
Animal with a complex stomach consisting of rumen, reticulum, omasum, and abomasum (cattle, sheep, deer, goats, antelopes)
Teeth designed for grinding, salivary glands do not produce amylase but large amounts of bicarbonate
4 Compartments of Ruminant Stomach
Rumen, Reticlum, Omasum, Abomasum
Largest, main site for microbial fermentation, NO enzyme-producing glands
No wall between reticulum and rumen, one large fermentation vat
Microbes in Rumen
Bacteria and Protozoa, Cocci for starch, Bacilli for cellulose
Volatile Fatty Acids (VFAs)
Product of microbial fermentation in ruminants, mostly propionic and acetic acids, must be removed/buffered or slow fermentation (bicarb from saliva)
"Hardware" stomach, anterior to rumen, looks like honeycomb, small, aids in food regurgitation, catches and holds foreign objects
Separates reticulo-rumen from abomasum, small, round, with folds, not super important, underdeveloped in mouse deer and camelids
Restrict large particles from moving out of rumen too soon, possibly also water reabsorption
Glandular/true stomach of ruminant, analogous to pig stomach, secretes HCl and enzymes
Pouch at junction of SI/LI, well-developed in non-ruminant herbivores (rabbits, horse, guinea pig)
Function of Cecum
Fermentation Vat, microbes create VFAs, and cellulose can be broken down
Cecum and Fermentation
Post-absorptive, bacteria less well-fed, diet of horse must be higher quality than of ruminant
why is NPN useless to nonruminants?
because it's in a form they cannot metabolize, ruminants can use it because their microorganisms remodel it to a usable form
3 Function of Rumen Bacteria
1. Digest carbs to VFAs
2. Remodel proteins, making essential aa, utilize NPN
3. Manufacture B vitamins
Feed Intake Protein
All proteins present in feed (Degradable Intake protein +Undegradable intake protein)
Degradable Intake Protein (DIP)
protein that is soluble and available to the microbes, they change it to NH4 and ketoacids, then to BCP (bacterial crude protein)
Un-degradable Intake Protein (UIP)
Insoluble protein unavailable to microbes (Feed N that makes it to SI unaltered)
Metabolic Protein (MP)
Protein that enters the SI (comes from Feed N and Bacterial N)
Bacterial Crude Protein (BCP)
Protein produced by bacteria in fermentation in the rumen
Escape (Bypass) protein
Get some aa in protein to reach cow tissue without being altered by microbes
Rabbit Circadian Rhythm in Digestion
Bacteria in cecum make cecotropes at night, rabbits then consume
Benefit of Cecotropes in Rabbits
Recycle N, benefit from formed vitamins
Rabbits and not enough fiber
lack of cecotrope formation, chronic soft stools, hairball formation
Total Digestible Nutrients. It includes the total amounts of digestible protein, nitrogen-free extract, fiber, and fat (multiplied by 2.25) all added together. Approximates energy content.
Gross Energy (GE)
Total energy content of a given weight of feed, measured as its heat of combustion by bomb calorimetry
Digestible Energy (DE)
The proportion of energy in a feed that can be digested and absorbed by an animal (GE-fecal energy)
Metabolizable Energy (ME)
The total amount of energy in feed less the losses in feces, combustible gases, and urine. Also called available energy (DE-E from urine and gas)
Net Energy (NE)
The portion of metabolizable energy that may be used by the animal for work, growth, fattening, fetal development, milk production and or maintenance (ME-E used in consumption, digestion and metabolism of feed)
(N feed - N feces - N urine) / N feed (grams)
(N feed - N feces - N urine) / N feed x 100 (%)
the difference between how many nutrients were in the diet before consumption and how many measurable nutrients are found in the animal feces
accounts for endogenous secretions (Nfeed-(Nfeces-Nendog))/Nfeed x 100
(Total nutrient consumed-total nutrient excreted)/(total nutrient consumed) x 100
Biological Value (BV)
A measure of protein quality, assessed by determining how well a given food or food mixture supports nitrogen retention.
Apparent Biological Value
(Nfeed-Nfeces-Nurine)/(Nfeed-Nfeces) x 100
True Biological Value
(Nfeed - (Nfeces - MFN) - (Nurine - EUN)) / (Nfeed - (Nfeces - MFN))
Endogenous Urinary N
metabolic fecal nitrogen
Why is the digestibility of nitrogen and the digestibility of protein the same thing?
We use N to calculate protein
What does 'endogenous' mean?
originating from within the body (did not come directly from the most recent feed)
What are the 2 different energy systems?
TDN and Calories
Lowest TDN Value
Highest TDN Value
225 (all fat)
Energy lost as heat due to the inefficiencies of metabolic pathways
How could 2 feeds have the same TDN and DE values, but be of different energy use to the animal?
Different heat increments, or urinary E
How could a feed be of little protein value even though its biological value is high?
How could a feed be of little protein value even though its digestibility is high?
Poor BV (Aa balance)
What does biological value depend on, or what is it indicative of (and the answer is not digestibility).
Essential aa balance (portion of digestible protein that is retained
Non-protein Nitrogen (urea, ammonia) Ruminants can use it
On what basis would you evaluate the protein in a feed for cattle? for hogs? Why the difference?
Cattle: CP (since they can use NPN)
Hogs: PV because it incorporates BV (non-ruminants need since they cannot use NPN)
Major Cereal Grains
Corn, wheat, Barley, Oats, Rye, rice, milo/sorghum
Minor Cereal Grains
Emmer-Spelt, Millet, Triticale,
Cereal Grains ranked by energy
Corn, wheat and milo and rye, barley and oats
TDN: 80%on as-fed basis
P, Ca: 0.25% P, 0.02% Ca
CP: Low (8.6%)
Lysine: (0.24%) Low (unless opaque-2)
Weight: 56 lbs/BU
High in fiber, low in energy, better for ruminants (90% value of corn for ruminants)
Substantial Lysine levels, but not all is available (pelleting helps)
Weight: 32 lbs./ BU
TDN: 71 (high fiber so low energy)
Protein: 11% (high for a grain)
If de-hulled, value equal or better to corn (TDN=84%, CP=16%
Oats Major Uses
Young animals starting on feed, calf creeps, wintering cattle, swine breeding herds, dairy rations for variety/bulk, sheep/cattle breeding rations, preferred grain for horses
Why do we feed corn to livestock?
What is opaque-2 corn?
high lysine corn
Who discovered opaque-2 corn?
Nelson and Mertz at Purdue Univ.
What impact has opaque-2 corn had on livestock feeding? on human feeding?
could feed to non-ruminants, but too variable, could help poorer countries not be deficient in lysine
What other genetic changes to the endosperm in opaque-2 corn have implications for livestock feeding?
the endosperm was soft and more susceptible to insect damage
Bind and precipitate proteins: make grains astringent, can be processed to remove or add MET to poultry diets to counter, found in sorghum
fruiting body of fungus; results in gangrene and LSD effects; found in rye
What is gossypol and what feed is it present in?
a toxin that causes symptoms like pneumonia, over come by feeding to ruminants, older individuals, or adding ferrous sulfate 1:1; cottonseed
What is trypsin inhibitor and what feed is it present in?
an enzyme that inhibits protein digestion found in soybean meal
What is aflatoxin and what feed is it present in?
a toxin created by the mold aspergillus flavus , corn and ground nut meal
What feeding problems or toxicities are associated with soybean?
Trypsin Inhibitor and urease
What feeding problems or toxicities are associated with cottonseed?
What feeding problems or toxicities are associated with rye?
ergot (dry gangrene, LSD)
What feeding problems or toxicities are associated with grain sorghum?
Tannin (cause grain astringency)
*What feeding problems or toxicities are associated with wheat?
*What feeding problems or toxicities are associated with oats?
low energy and expensive
What feeding problems or toxicities are associated with barley?
low energy, lysine not always available
What feeding problems or toxicities are associated with peanut meal?
What feeding problems or toxicities are associated with blood meal?
not palatable, can be difficult to get good lysine
What is the effect of test weight on livestock feeding?
Only price considerations
What are the major mycotoxins affecting livestock?
Aflatoxin, Deoxynivalenol, Zearalenone, Fumonison
produced by aspergillus flavus, carcinogenic
Produced by Gibberella Zea, feed refusal in pigs
Produced by Gibberella Zea, estrogenic (causes repro upset)
Produced by Fusarium moniliforme, kills horses
What are the methods of processing corn, wheat?
Hammer mills, roller mills (much better for wheat than hammer), steam flaking, pelleting
What are the byproducts of the brewing industry and what are their characteristics?
Brewer's grains, spent hops, dried yeast, malt sprouts
What are the characteristics of Brewer's grains?
TDN of oats 70%, high CF 15%, high P 1%, good dairy cattle feed (low palatability)
What are the characteristics of spent hops?
vegetative plants and fed to cattle
What are the characteristics of Brewer's dried yeast?
high in CP 40-45% & ash 5-10%, good source of vitamins
What are the byproducts of the distilling industry and what are their characteristics?
Distiller's grains; Distiller's condensed or dried soluble; DDGS; Distiller's dried yeast
What are the characteristics of distiller's grains?
25%CP, 8%CF, 82%TDN, what's left after removing the alcohol from the distilled grains, mostly feed to ruminants
What are the characteristics of DDGS?
can feed a lot but protein and phosphorus will be in excess
What are the characteristics of distiller's dried yeast?
good for beef, dairy, and sheep
What protein supplements are good substitutes for soybean meal?
rapeseed, canola meal, peanut meal
What other oilseed meals are protein supplements (other than SBM) and what are their attributes?
cottonseed meal, linseed meal, peanut meal, copra (coconut meal), canola
What are the attirbuts of cottonseed meal?
Similar CP, lower CF, ½ lysine, gossypol
What are the attributes of linseed meal?
less CP, lower CF, 1/3 lysine, glossy coat (musins) limit in swine/poultry, fed to ruminants
What are the attributes of peanut meal?
similar CP, lower CF, ½ lysine, danger from aflatoxin, feed to ruminants
What are the attributes of copra meal?
highly variable, fed to ruminants
What are the attributes of conola meal?
What are the attributes of sunflower meal?
~same CP, variable CF, ½ - 2/3 lysine, best as ruminant feed
What are the attributes of rapeseed meal?
similar CP, 2/3 lysine, danger from erucic acid and myrosinase enzyme (glucosinolates to toxic compounds)
Why is SBM heated?
to denature trypsin inhibitor
What makes the difference between 44 and 48.5% SBM?
48.5% is dehulled, 44% has hulls added back in to get to the 44%
What are the major byproducts fed to livestock from corn processing by dry milling?
Corn Bran; Corn Germ Meal; Hominy Feed
What animals are fed with Hominy feed and why?
any? High energy and palatable
What are the major byproducts fed to livestock from corn processing by wet milling
corn gluten meal, corn gluten feed