Growth and Development
What is growth?
Increase in body weight until maturity is reached. In animal production it is an increase in animal tissue: muscle, fat, and bone.
True or False: All meat sold is inspected and will have a shield of approval on the package.
True
What are the 6 Classes of Nutrients?
1. Water
2. Carbohydrates
3. Protein
4. Fats
5. Minerals
6. Vitamins
What are the functions of the digestive tract?
Prepare nutrients for absorption
Store nutrients
Build useful products
Reject unused and broken down residue
What are the 5 classes of feeds? Give one example of one class.
1. Concentrate - corn, sorghum, barley, molasses, bakery by- products
2. Roughage/Forage - Hay, silage, grass, straw
3. Protein Supplement - Soybean Meal, Meat and bone meal, Urea, Fish meal
4. Non-nutritive Additives - Antibiotics, Ionophores, Flavor components, Hormone - like compounds
5. Vitamins/Minerals - salt mix, mineral mix, vitamin mix
List and rank body processes from first importance (lowest nutrient levels) to last importance (highest nutrient levels).
Maintenance - support of body processes
Growth - increase in weight or size
Reproduction - proliferation of species
Animal Products - used for human consumption
Name the 4 primary beef wholesale cuts.
Chuck
Rib
Loin
Round
What are the differences between soluble and insoluble carbohydrates? Name an example of an insoluble carbohydrate and a species of animal that can utilize them.
Soluble: Simple, containing alpha linkages
Insoluble: Complex, containing beta linkages
-Examples: Cellulose, hemicellulose, lignin
-Utilized by ruminants (cattle, sheep, goats) due to microbes being able to break down the beta linkages
What are the three different classifications of animals? Rank them by complexity of digestive system (simplest to most complex).
Carnivores - meat eaters
Herbivores - plant eaters
Omnivores - plant and meat eaters
Ranking: Carnivores (monogastrics), Ominvores (intermediate tract), Herbivores (ruminants or monogastrics and hindgut fermenters)
Which class of feed is highly digestible, high in energy, and low fiber? Why is this class of feed fed?
Concentrates - Primarily fed for energy due to high concentration of carbohydrates
How does the proportion of body composition composed of blood, hide, and viscera change as an animal grows?
It decreases. Muscle and Fat continue to grow sigmoidally proportional to weight/size whereas the amounts of blood, hide, and viscera grow more linearly proportional to weight/size.
What are the three different types of muscle and where are they found?
Which is most commonly consumed by humans?
Skeletal - body muscle (quadriceps, brisket)
Cardiac - heart
Smooth - internal organs (intestines, liver, spleen)
Skeletal muscle is most commonly consumed by humans.
What is the primary role of protein? What is an essential ammino acid?
Primary role of protein is to supply protein (amino acids).
An essential amino acid is not formed in the body in adequate amounts and must be supplied in the diet.
List the physiological differences between a monogastric and a ruminant stomach.
Ruminants have a stomach with four compartments: rumen, reticulum, omasum in addition to the abomasum ("true stomach"/ glandular stomach), that takes up a greater percentage of total GI tract capacity.
Monogastrics only have a glandular stomach that varies in size.
What is the difference between a protein supplement and a non-nutritive additive? Give an example of each.
Protein Supplement - Feeds containing greater than 20% crude protein. Example: Soybean meal, Meat and Bone meal, Urea, Fish meal
Non-Nutritive Additive - Works to increase gain efficiency. Examples: Antibiotics, Ionophores, Flavor compounds, Hormone-like compounds
What is efficiency in terms of growth?
List the following animals from most feed efficient to least feed efficient:
Swine, Fish, Cattle, Sheep, Broilers (meat chickens)
Efficiency: Units of input per unit of output
-Typically defined as units of feed (lbs or kg) per unit of gain (lbs or kg)
Most efficient to least efficient:
Fish (1.1:1)
Broilers (2:1)
Swine (2-3:1)
Sheep (4-6:1)
Cattle (7:1)
How do you determine yield grade?
Beef yield grading uses adjusted fat thickness, % Kidney, pelvic and heart fat (KPH), and rib eye area to calculate the expected amount of closely trimmed retail cuts.
What is TDN and how do you calculate it?
TDN - Total Digestible Energy
TDN = Gross Energy - Fecal Energy
Explain the process of rumination and eructation.
Rumination - Rechewing coarse material
• Steps in the process: Regurgitation, Remastication, Reensalivation, Reswallowing
• Reduces particle size and increases salivary flow
Eructation- Expelling gases produced from microbial fermentation
• Failure to expel gases = bloat
What is Dry Matter? How do you calculate % Dry Matter in a feed?
Dry Matter - Actual nutrients in a feed minus any moisture (Think a dry sponge vs wet sponge)
% Dry Matter:
Amount of Feed - Amount of Moisture = Amount of Dry Matter
Dry Matter/Total Feed = % Dry Matter
What is the shape of a growth curve?
What are (at least) 3 things that can effect the growth curve?
Nutrition
--High Nutrition -> Able to push growth a little faster, this isn't always a good thing
--Low Nutrition -> Limited growth due to nutrient requirements not being met
-- Forages vs Concentrates
--- A high concentrate diet is very energy dense and promotes increased growth and fat deposition (why corn and barley are commonly seen in feedlot diets)
-Breed
-- Early vs Late Maturing
-- Frame Size (Large vs Small)
-- Ability to deposit fat (ex. Simmental vs Wagyu)
-Environment
-- Temperature
--- Too hot -> decreased intake and less growth
--- Too cold -> increased intake, but more energy demand to keep warm
Define Quality grade and give 2 examples of a grade.
Grade of meat based on amount of marbling (intramuscular fat) in the longissimus dorsi,
maturity of carcass, gender, meat and fat color.
Possible grades:
Young animal - Prime, Choice, Select, Standard
Old animal - Commercial, Utility, Cutter
Classify the following as a macro mineral, micro mineral, fat soluble vitamin, or water soluble vitamin.
Calcium (Ca)
Zinc (Zn)
A
B (complex)
Potassium (P)
K
Selenium (Se)
Calcium - Macro Mineral
Zinc - Micro Mineral
Vitamin A - Fat Soluble
Vitamin B complex - Water Soluble
Potassium - Macro Mineral
Vitamin K - Fat Soluble
Selenium - Micro Mineral
1. Selection - selecting food based on 5 senses and learned aversions
2. Prehension - The process of getting the food into the mouth
3. Mastication - chewing
4. Deglutition - swallowing
5. Digestion - physical changes: Chewing, swallowing, crushing, peristaltic motions. Chemical changes: enzymes, bacteria, microorganisms, digestive juices
6. Absorption - utilization of nutrients, crossing the epithelium and entering the blood.
7. Circulation - Transport of nutrients to site of storage and use, via blood or lymph
8. Metabolism - cell level utilization
9. Excretion - body voids material (through defecation, urination, exhalation, sweating, wearing off of cells)
According to the Van Soest Fiber System there are two types of fibers. What are each of these called? What is isolated in each? What is negatively correlated with each?
Neutral Detergent Fiber (NDF): isolates cellulose, hemicellulose, and lignin. Is negatively correlated with feed intake.
Acid Detergent Fiber (ADF): isolates cellulose and lignin. Is negatively correlated to digestibility of feed.