Animal Nutrition 3190

Exam 1

The act of eating

Ingestion

The term for when the body takes up small molecules from the digestive compartment

Absorption

Breaking down food into molecules small enough for the body to absorb

Digestion

When undigested material passes out of the digestive compartment

Elimination

What two things does processing do?

Increases surface area, increases digestability

What are the three volatile fatty acids?

Acetate, butyrate, propionate

What does volatile mean?

It can evaporate and has odor

What are the three structural carbohydrates?

Cellulose, hemicellulose, and lignin

Which structural carbohydrate is indigestible

Lignin

What does it mean when a plant has a lot of lignin? (in terms of digestibility?)

It is less digestible

As plants age, what happens to the fiber and digestibility?

Fiber increases and digestibility decreases

What type of feed is often the seed of a plant, has low levels of carbohydrates, and a higher concentration of digestible energy?

Concentrate

This feed is defined by the fraction of the cell wall

Roughage/forage

Leaves and stems of grasses (What type of feed)

Forages

Seeds of cereals, oilseed plants (What type of feed)

Grains

Why type of feed is turnips, beets, and potatoes

Roots, tubers

What type of feed are cereal seed coats and oilseed meals

Byproducts

What are the two families of cultivated forages?

Grasses and legumes

Which has more nitrogen, grasses or legumes? Why/

Legumes have more nitrogen because they have special nitrogen-fixing bacterial on their roots.

What two things determine the nutritive value of a forage and why do both matter?

Nutrient density and digestibility. This is important to consider when harvesting food and when feeding animals.

Content of specific nutrient/unit weight

Nutrient density

Ability of animal to digest and absorb nutrients

Digestibility

What is the formula for apparent digestibility %?

(dietary intake - feces output/dietary intake) x 100

Why do we call it apparent digestibility instead of just digestibility when evaluating digestibility based on feces output?

It’s called apparent because it’s the best estimate of digestibility since it can’t be measured with 100% effectiveness. It only considers what is consumed and what is excreted.

What is the apparent digestibility of dog food if my dog consumes 300g DM and excretes 32g DM?

(300g - 32g)/300g x 100 = 89.33%

NDF stands for

Neutral detergent fiber

NDF is made up of… (3 things)

Cellulose, hemicellulose, lignin

Neutral detergent fiber contains the …. parts left from the neutral detergent solution.

ADF stands for

acid detergent fiber

ADF contains the _______ parts left from the acid detergent solution. (Soluble/insoluble)

soluble

ADF is made up of (2 things)

Lignin and cellulose

Feeds with a high ADF are ____ in digestibility. (Lower/higher)

lower

________ is soluble in the acid detergent solution and is not included in ADF. (a structural carbohydrate)

hemicellulose

30 grams of your sample is NDF and 25 grams is ADF. ____ grams of your sample are hemicellulose.

5

1. Medical experiment or test performed on a living thing.

2. Medical experiment or test performed in a dish or test tube.

1. in vivo

2. in vitro

To get a better estimate of the digestibility of the hay you send it into a lab where they put a small amount of it into different pH solutions to mimic the environment of the digestive tract. This is an _________________ (in vivo or in vitro) lab assessment of digestibility.

In vitro

Now you want to determine exactly how digestible your hay actually is for your sheep, so you take 5 sheep and record the amount fed and the amount of feces and urine. This is an _________________ (in vivo or in vitro) lab assessment of digestibility.

In vivo

You feed 100 grams of hay to a sheep and collect 15 grams of feces. According to your experiment, this hay has an apparent digestibility of _____________ %.

85

Post-absorption utilization of nutrients

Metabolism

A substance that must be obtained in the diet because the body either cannot make it or make enough of it

Essential nutrient

A nutrient that the body can make sufficient quantities of if it is lacking in the diet

Nonessential nutrient

What are the four essential nutrients

Essential amino acids, essential fatty acids, vitamins, mineral

A ______ is a nutrient that is provided (but not necessarily required) in a relatively large amount in the diet.

Macronutrient

(T or F) Macronutrients are required in the diet

False

What are the four macronutrients

Carbohydrates, proteins, lipids, water

A _______ is a nutrient that is needed in relatively small amounts in the diet

Micronutrient

What are the two micronutrients

Vitamins and minerals

(T or F) Stomach should be associated with HCL

TRUE

A more sophisticated large intestine means the animal can absorb more _____. (High NDF and ADF feeds)

Fiber

(T or F) The body does not absorb macronutrients because they are too large.

T

When carbohydrates are digested it results in…

Glucose

When proteins are digested it results in…

Amino acids

When fats are digested it results in…

Fatty acids

Ruminants and nonruminants are _______ fermenters

Pregastric

Cecal digesters and colonic digesters are ______ fermenters

Hindgut fermenters

What are the two types of colonic digesters

Sacculated and unsacculated

_____ fatty acids break down enamel and cause cavities

Volatile

How do rumens get their energy?

From absorbing volatile fatty acids straight into the rumen walls

How do ruminants get their protein

From digesting microorganisms in the “true stomach”

Nonruminant pregastric fermenters use _______ stomachs. They allow for some fermentation. However, they must eat more digestible forage.

Sacculated

What are the two types of hindgut fermenters

Cecal and colonic digesters

The _____ is a dead end or blind sac used for digestion.

Cecum

Which can consume more structural carbs, sacculated or unsacculated colonic digesters.

Sacculated

(T or F) All mammals have some fermentative capacity that allows for utilization of ingested fiber.

True

This is how animals get feed into their mouth.

Prehension

Digestion in the mouth. Also known as chewing. Physical reduction of feed size.

Mastication

This is a reflex initiated by the presence of food in the pharynx. (swallowing)

Deglutition

Movement in and out of the stomach is controlled by circular muscular structures called the _______. There is one at the top and bottom of the stomach.

Sphincters

Partially digested food is called ____

Chyme

(T or F) Plants are more digestible than meat.

False