Animal Nutrition Exam 1

Act of eating.

ingesiton

Process of breaking food down into molecules small enough for the body to absorb.

Digestion

Taking up small molecules from the digestive compartment.

Absorption

Elimination

Undigested material passing out of the digestive compartment.

Process of transforming carbohydrates into alcohol and carbon dioxide or organic acids through yeast, bacteria, or a combination of the two.

Fermentation

Structural Carbohydrates in Plants

Cellulose, hemicellulose, and lignin.

Indigestible Structural Carbohydrate

Lignin.

Concentrates

Examples include grains and soybeans

Examples include leaves and stems of grasses, legumes, brassicas

Forages

What are examples of Grains

Examples include seeds of cereals, oilseed plants

Roots, tubers

Examples include turnips, beets

What are examples of byproducts

Examples include cereal seed coats, oilseed meals, distillers grain

Nutritive Value of Forage

Determined by nutrient density and digestibility, both of which are essential for overall value.

Apparent Digestibility definition, not equation

This term is used to evaluate digestibility based on feces output. It considers factors like microbial use of nutrients, excretion of digestive enzymes, and epithelium shedding.

Is fiber in the stem of a plant or fiber in the leaf of a plant more digestible?

Leaf

Is the fiber at the top or bottom of the plant more digestible?

The top of the plant

What are examples of environmental factors that will increase structural carbohydrates?

High temperatures, high light intensity, and maturity

What are examples of environmental factors that will decrease structural carbohydrates?

Low light, moisture deficit, moisture excess, and low soil fertility

Substance that must be obtained in the diet, because the body either cannot make it or cannot make adequate amounts of it

Essential nutrient

Nonessential nutrient

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

Macronutrients

nutrient that is provided in a large amount in the diet

Nutrient that is needed in relatively small amounts in the diet

Micronutrients

What are the 4 macronutrients?

carbohydrates, proteins, lipids, water

What are the two micronutrients?

vitamins and minerals

3 structural carbohydrates

hemicellulose, cellulose, lignin

What does NDF stand for?

Neutral Detergent Fiber

2 structural carbohydrates in ADF

cellulose and lignin

What does ADF stand for?

Acid Detergent Fiber

What structural carbohydrate is not included in ADF?

Hemicellulose

Solubility is high = digestibility is (high or low)

High

In vivo

Digestibility assessment done on a living animal

Digestibility assessment done in a lab dish or test tube

In vitro

Does fermentation in pregastric fermenters happens before or after it reaches the stomach?

Before the stomach

Do legumes or grasses have a higher nitrogen content?

Legumes

Do hindgut fermenters ferment feed before or it reaches their stomach?

After the stomach

What is an example of a nonruminant pregastric fermenter?

Kangaroo

Pregastric Ruminants

Examples include cattle, sheep, deer

Pregastric Nonruminants

Examples include hippo, kangaroo, hamster

Examples include rabbit, rat, mice. What type of digesters are they?

Hindgut cecal digesters

A horse, pig, and elephant are examples of _________

Hindgut colonic fermenters

Examples of Hindgut Unsacculated digesters

Examples include panda, dog, cat

True or False. All mammals have some postgastric fermentation.

True

3 volatile fatty acids

acetate, propionate, butyrate

Act of seizing and conveying feed to mouth

Prehension

Mastication

physical reduction of feed size; chewing

Deglutition

propulsion of food to stomach by esophageal peristalsis; swallowing

True or False. Ruminants absorb rumen microbes in their small intestine.

True

True or False. Hindgut fermenters absorb microbes from fermentation in their small intestine.

False

muscles that open and close to allow feed into/through GI tract

Sphincters

What is Chyme

partially digested food mixture leaving the stomach

True or False. The stomach contains little muscle.

False

True or False. The stomach kills all bacteria.

False (kills nost)

Inactive form of pepsin

Pepsinogen

What does HCl do

activates pepsinogen into pepsin

Mucous cells secrete…

secrete mucus

What do Parietal cells secrete

secrete HCl

These cells secrete pepsinogen

chief cells

G cells (enteroendocrine cells) secrete…

secrete gastrin

3 phases of gastric secretion and motility

cephalic phase, gastric phase, intestinal phase

Describe the cephalic phase

Induced by thinking of, smelling, tasting, or chewing food. Increases saliva production, gastric motility, and enzyme and HCl secretion

This phase depends on presence of food in stomach. G cells release gastrin. HCl secretion increases

Gastric phase

This phase is stimulated by duodenal distension (stretching). Decreases pH, HCl secretion, and gastric motility. CCK is released

Intestinal phase

origin: stomach/abomasum

function: stimulates HCl and pepsinogen secretion, increases stomach motility

Gastrin

origin: duodenum

function: stimulates pancreatic secretions. Slows stomach motility and acid production

Secretin

origin: duodenum

function: stimulates bile and pancreatic secretions

Cholecystokinin (CCK)

Origin: duodenum

Function: inhibit stomach motility and secretion of acid and enzymes

Gastric Inhibitory Protein (GIP)

receives bile and pancreatic secretions. Active site of digestion

duodenum

active site of nutrient (fats, proteins, carbs) digestion

Jejunum

active site of nutrient (water, vitamins, minerals) digestion. Some bacterial presence (fermentation)

Ileum

Is the pH higher or lower in the small intestine than in the stomach?

Higher

True or False. Secretory cells stay on the same spot of the villi until they die.

False

3 things that increase small intestine wall surface area

Mucosa folds, villi, microvilli (brush border)

acts as a lubricant and buffer to protect intestinal wall

Intestinal mucous

enzyme that breaks down carbohydrates

Amylase

What is lipase

enzyme that breaks down fat

Enzyme that breaks down proteins

Proteases

Which of the following is not an enzyme: pepsin, bile, amylase, or lipase?

Bile

Do all animals have some degree of hindgut or foregut fermentation?

Hindgut

3 main functions of large intestine

stores feces, absorbs water and electrolytes, hindgut fermentation

If we remove water from a food does the weight of sugar in the food increase, decrease, or stay the same?

Stays the same

If we remove water from a food, does the percent of sugar in the food increase, decrease, or stay the same?

Increase

Sphincter that controls food leaving the stomach and entering the small intestine

Pyloric valve

What is the typical stomach pH

2-3

Parietal cells secrete…

HCl

These cells secrete pepsinogen. This is converted into pepsin when mixed with HCl.

Chief cells

These cells secrete gastrin to regulate stomach emptying

Entero-endocrine cells (G-cells)

What hormone is released by the small intestine and decreases HCl secretion and gastric motility? (Essentially tells the stomach to stop releasing food into the small intestine)

Cholecystokinin (CCK)