Animal Nutrition Exam 1

Digestive System

______:

• The portal for nutrients to gain access to the circulatory system.

  • Food stuffs are broken down to very simple molecules → resulting surgars, amino acids, fatty acids etc. are then transported across the GI tract lining into the bloodstream.

Absorption

Digestion → ______

Digestive System

Specific feedstuffs animals can utilize is dependent on the type of _______ they possess.

Monogastrics

3 Classifications of GI Systems

• _________

• 1 stomach

  • Chickens

  • Pigs

  • Turkeys

  • Dogs

  • Cats

Ruminants

3 Classifications of GI Systems

• ______

• 1 compartamentalized stomach with FOUR compartments

  • Cattle

  • Goats

  • Sheep

  • Deer

  • Giraffes

  • Buffalo

  • Bison

Hind Gut Fermentors

3 Classifications of GI Systems

• ______

• Horses

• Rabbits

• Ostrich

Mouth

The starting point that begins the digestive process

Select their food

The beaks of chickens are trimmed so they cannot do what?

Lips

Mouth: ______

• Grab food

• Select/nitpicking types of foods

Domestic Animals

Selection of Food

• Good for wild animals to avoid dangers with limited resources

• Bad for _________ as we value their nutrition, these animals have formulated diets and we don’t want them to select.

Selection of Food

Ways to prevent the ________

• Kibble/Pellets → make it difficult for animals to sort.

• Trim beaks

• Add Molasses/something animals like

• Total Mixed Ration (TMR)

• Chop/make particles smaller

• Add water to avoid the selecting out of dustry foods.

Tongue

Mouth: Tongue and Teeth

_______: used for grasping food, mixing, and swallowing.

Teeth

Mouth: Tongue and Teeth

_____: Tear and chew the feed into smaller particles that may be swallowed

Bite

_____ effects how an animal grabs food and eats.

Salivary Glands

Mouth: _________

• IMPORTANT FOR DIGESTION

• Excrete saliva, which serves many purposes:

  • Water to mositen food

  • Mucin to lubricate for swallowing

  • Bicarbonates to buffer acids

  • Enzyme amylase to break down carbs

pH

Saliva Buffer Acids

• especially important for ruminants.

• Stabilize ____

  • Important because they prevent ulcers (too much acid), damaged teeth, sustain microbes → microbiome needed for digestion (changes in pH kills the microbes)

  • *Cows cannot digest cellulose (grass) → need microbes

Small

Enzyme Amylase - In Saliva (breaks down carbs)

• Chemical digestion in the mouth is not that important because food does not stay in the mouth long enough for enzymes to do anything.

• Retention time for food in the mouth is ________

• Less than 10% of chemical digestion.

Esophagus

_______- doesn’t do much for digestion

• The hollow muscular tube that leads from the mouth to the opening of the stomach.

Sphincters

Horses cannot throw up because their _______are too strong → horses had to run on a full stomach, the one’s that stopped to throw up were eaten.

Stomach

______

• A hollow tube that contracts and relaxes to integrate digetsive juices with the food causing it to breakdown.

Small Intestine

The place when most digestion occurs ~ stays here longer than in the stomach.

Small Intestine

The next organ in the digestive system that is controlled by a sphincter muscle that helps move food into and through the tract.

Made of 3 Segments

1. Duodenum

2. Jejunum

3. Ileum

Cannulated Pig

• _______

• Pig must be in good condition or else the data is invalid

Duodenum

Segments of the Small Intestine

_______

• First Segment

• Uses secretions from the pancreas and intestinal wall to break down proteins, strarches and fats.

Jejunum and Ileum

Segments of the Small Intestine

___________

• Second and third segements

• Where ABSORPTION occurs

  • Absorption is the process which nutrients are passed from the intestine into the bloodstream

Absorption

_________- the process which nutrients are passed from the intestine into the bloodstream

Villi

Walls of Jejunum and Ileum

______: small fingerlike projections that protrude from the epithelial lining of the intestinal wall.

Entherocytes

Walls of Jejunum and Ileum - Villi

• _________: specialized cells for absorption in the small intestine

Blood Vessels

Walls of Jejunum and Ileum - Villi

• Connected to ______ to allow nutrients to circulate in the blood.

Surface Area

Walls of Jejunum and Ileum - Villi

• Increases ______ for absorption

Semi-permeable membrane

Walls of Jejunum and Ileum - Villi

• Absorbs nutrients through a _____________, these particles can pass through by a process called DIFFUSION

Large Intestine

The last organ of the digestive system, which mostly absorbs WATER and conatins two segments

• Cecum

• Colon

Cecum

Segments of the Large Intestine (absorbs water)

1. _______

• Fibrous food such as hay and grass is broken down into usable nutrients

• Comparable to the appendix in humans

• Large in horses - hind gut fermentors

Colon

Segments of the Large Intestine (absorbs water)

2. _______

• Provides a storage space for waste from the digestive process and is the largest part of the large intestine

Rectum

Large Intestine - _____

• The terminal end of the large inestine and the entire digestive tract.

GI Road Map: Monogastrics

Pancreas

GI Road Map: Monogastrics

________: Secretes enzymes for digestion

Liver

GI Road Map: Monogastrics

_______: Produces bile (proteins/nutrients) → that bile is stored in the gall bladder.

*Horses do not have a gall bladder

Bile

GI Road Map: Monogastrics

_______: emulsifies fat/lipid digestion

Fats/Tallow

You should not give horses _______:

• Causes issues because horses DO NOT have a gallbladder to store bile to emulsify large quantities of fats so it can be digested.

• *Horses still produce bile but it is continously/slowly released.

Simple

Monogastrics: Pigs, Dogs, Cats

Monogastric = 1 “_____” stomach

Digestion

_______: the chemical/physical/mechanical breakdown of macronutrients into micronutrients

Mouth/Teeth

Monogastrics: Pigs, Dogs, Cats

• Mechanical digestion begins in the _______ unless the animal eats really fast

Chewing

Monogastrics: Pigs, Dogs, Cats

MOUTH

• Mechanical breakdown of foodstuffs by _____ (reduces particle size, increases surface area for enzyme action)

Amylase

Monogastrics: Pigs, Dogs, Cats

MOUTH

• Saliva added as a lubricant and, in some species, contains _____ to begin starch digestion

Amino Acids

Proteins → Peptides → _________ (what is actually digested)

Esophagus

Monogastrics: Pigs, Dogs, Cats

______

• Tube connecting the mouth to the stomach

Stomach

Monogastrics: Pigs, Dogs, Cats

______

• Produces acid and enzymes

• Enzymatic digestion of protein begins

• Food stuffs reduced to liquid form

Protases

In the stomach of a monogastric, what are the enzymes for digestion called?

Small Intestine

In monogastrics, most chemical digestion occurs in the ______

Liver

Monogastrics: Pigs, Dogs, Cats

________

• Center of metabolic actvity in the body

• Major role: provide bile salts to the small intestine for fat digestion and absorption

Gall Bladder

Monogastrics: Pigs, Dogs, Cats

______

• Small pouch under the liver

• Stores Bile

Pancreas

Monogastrics: Pigs, Dogs, Cats

______

• Provides a mixture of digestive enzymes to the small intestine to help in digestion of fats, carbohydrates, and proteins.

Small Intestine

Monogastrics: Pigs, Dogs, Cats

_______ (Place of chemical digestion and absorption)

• 3 Segments → Duodenum, Jejunum, Ileum.

• Site of final stages of chemical enzymatic digestion

• Where almost all nutrients are absorbed

Beak (Mouth)

Monogastrics: Avian

_____

• Used for grabbing food and important to feed something ground up.

• No lips, no teeth, no chewing.

Esophagus

Monogastrics: Avian

______: tube connecting the mouth to the crop.

Crop

Monogastrics: Avian

_____: pouch where food is SOAKED, softened, and stored (very little digestion)

• Outer-pocketing of the esophagus

Proventriculus

Monogastric: Avian

________

• True stomach for birds

• First significant amount of digestive juices added like HCl

• Physical breakdown of food hasn’t begun yet

Gizzard

Monogastrics: Avian

_______ (GRIND)

• Muscular organ used to grind and break up food

• Stones or grit found here to help with the break up process

• Act like teeth for oher monogastrics

• Small Intestine

• Ceca

• Large Intestine

Monogastrics: Avian

• ____

• ____

• ____

all have the same function

Cloaca

Monogastrics: Avian

______

• Digestive and renal (urinary) system waste exits here

• Urine and feces are excreted together

Review

Review

Review

Review

Complex

Ruminants = A “____” stomach

Ruminants

Examples of ______

• Cattle

• Sheep

• Buffalo

• Deer

• Giraffe

• Antelope

• Goat

• Moose

• Elk

• Llamas

• Alpacas

• Bison

Cud

Characteristics of Ruminants

1. Chewing ___

Dental Pad

Characteristics of Ruminants

2. No upper front teeth

• Instead, they have a ______ that works with the lower front teeth (incisors) in tearing off feedstuff

*Tongue grab and lascerate food with dental pad

Enzymes

Characteristics of Ruminants

3. Saliva does not contain ____

• But they produce it in large quantities

Bicarbonates

Although ruminant saliva does not contain enzymes it does contain ______ which is important to all animals as it helps control pH in the stomach and keep the microbe population alive in the stomach.

Ruminate

The Bicarbonates in saliva are extra important for ruminates because they _____ (come back up → redcues particle size and produces more saliva) more of this means more saliva → important to keep bacteria in stomach alive

Monogastrics

Ruminants

*Mouth, esophagus, liver, panceras, gall bladder, small intestine, and large intestine have functions similar to _____

Ruminants

____ eat as much as they can → sit and ruminate for hours → prey animals need to eat as much as they can while they have food source: hide and have time to ruminate.

Stomach

Ruminants

_________

• Structure and function is the main difference between ruminants and monogastrics

• Multi-compartmented: rumen, reticulum, omasum, abomasum → microbes in rumen can tolerate large variations in pH

Rumen

Four Compartments of the Stomach - Ruminants

1. ______: Paunch

Reticulum

Four Compartments of the Stomach - Ruminants

2. _____: Honeycomb

Omasum

Four Compartments of the Stomach - Ruminants

3. ______: Book pages or the “Butcher’s Bible”

Abomasum

Four Compartments of the Stomach - Ruminants

4. ________: True or glandular

Cud Chewers

Ruminants are often called “________”

Rumen

Ruminants

______

• Large anaerobic fermentation vat

• Food is soaked, mixed, and fermented by bacteria

• Contains finger-like projections called papillae that absorb nutrients through the wall into the bloodstream to provide energy

• “Shag carpet” appearance

• Saturated with gases and in constant motion

Rumen

____ absorbs

• Water

• Ammonia

• Some Vitamins and Minerals

• Some Acids

• Volatile Fatty Acids

Contractions

Ruminants

Rumen

• ______ occur at a rate of 43 per minute

  • Purpose: mix contents, aid in eructations of gases, move fluid and fermented feedstuffs into the omasum

Microorganisms

Ruminants

Rumen

• Houses ________ → highly concentrated: grow bacteria and digest them in the small intestine

  • Protozoa - 100,000 per gram of rumen fluid

  • Bacteria + Fungi - 100 million per gram of rumen fluid

Fats

____ = High Energy

• Volatile Fatty Acids

• Microbial Protein

• Vitamin B + K Complexes

VFA’s are also absorbed and produced in the rumen

Ruminants

Rumen

• Microorganisms digest roughages to make

  • _________

  • _________

  • _________

• ____ are also absrobed in the rumen

Volatile Fatty Acids (VFA’s)

In the Rumen of ruminants, microbes ferment carbohydrates, _____ are produced as a by-product.

• Where they are Absorbed in the rumen and travel to the liver where ATP is produced.

Microbial protein

The ruminant protein supply comes from _______

Cellulose

Ruminants

Advantages of Microbial Digestion

1. ______ digestion via microbial fermentation

• This is a fiberous carbohydrate - many glucose together

• Humans cannot digest cellulose

• This is how horses digest it in the large intestine

Vitamin B

Ruminants

Advantages of Microbial Digestion

2. Microbial synthesis of _____

Abomasum

Ruminants

Advantages of Microbial Digestion

3. Microbial protein formation in the rumen (digested in the _____)

Non-Protein Nitrogen

Ruminants

Advantages of Microbial Digestion

4. Ability to use ______ (NPN) → urea: commonly used as fertilizer and to make amino acids

• Compound that is not a protein but contains nitrogen

Energy Fermentation

Ruminants

Disadvantages of Microbial Digestion

1. _______ lost (heat loss = 5-6% gross energy)

Gas

Ruminants

Disadvantages of Microbial Digestion

2. ____ production (methane production = 6-8% of gross energy)

*Burping

modification

Ruminants

Disadvantages of Microbial Digestion

3. Microbial ____of dietary nutrients

Cheap Proteins

Ruminiants Microbial Modifcation of Nutrients

• Good for when you are feeding _____: as the microbes modify and make their own proteins necessary for the body

Good formulated diet

Ruminants Microbial Modifcation of Nutrients

• Not good when you are feeding a _________ → microbes get first dibs

  • May want to use a slow release feed: coat/protect the nutriens in fats, so it can be digested in the small intestine but not the rumen so microbes cannot access it

Glucose

Ruminants

Disadvantages of Microbial Digestion

4. ____ shortage

• Low Blood Sugar → Cellulose is low on the glucose index and a low digesting carb meaning it does not reach the blood stream vey fast.

• Ruminants don’t get sugar highs

Glucosenogenesis

Becuase microbial digestion leads to a glucose shortage in ruminants, and ruminants need glucose to make milk ruminants carry out ________, which is the making of glucose out of something that is not a carbohydrate (ex: protein)

CO2

Ruminants

End Products of Ruminal Fermentation

1. (80%) ____ - Green house gas and energy loss for the animal (belching → burping)

*Most common

CH4

Ruminants

End Products of Ruminal Fermentation

2. (20%) ____- Green house gas and energy loss for the animal (belching → burping)

Volatile Fatty Acids

Ruminants

End Products of Ruminal Fermentation

3. _____ - drives the pH down, therefore saliva (buffer → bicarbonates) is more important than in non-ruminants. - Acids that drive pH down, mild acids → we produce HCl in stomach ~ much stronger